RUS Performance Specification for Line Concentrators

SUMMARY: The Rural Utilities Service formerly the Rural Electrification

Administration (RUS) hereby amends its regulation on RUS

Telecommunications Standards and Specifications for Material, Equipment

and Construction by codifying the RUS bulletin concerning RUS

Performance Specification for Line Concentrators, RUS form 397g. This

specification has been incorporated by reference and will be rescinded

after the effective date of the final rule. The specification updates

the end product performance requirements brought about through

technology advancements since this specification was last issued on

July 29, 1985.

DATES: Effective date. This regulation is effective on September 28,

1995.

Incorporation by reference. Incorporation by reference of

publications listed in this final rule is approved by the Director of

the Federal Register as of September 28, 1995.

FOR FURTHER INFORMATION CONTACT: Mr. John J. Schell, Chief, Central

Office Equipment Branch, Telecommunications Standards Division, U.S.

Department of Agriculture, Rural Utilities Service, room 2838-S, AG Box

1598, Washington, DC 20250-1500. Telephone: 202-720-0671.

SUPPLEMENTARY INFORMATION:

Executive Order 12866

This rule has been determined to be not significant for purposes of

Executive Order 12866 and therefore has not been reviewed by OMB.

Executive Order 12778

This rule has been reviewed under Executive Order 12778, Civil

Justice Reform. This rule:

(1) Will not preempt any state or local laws, regulations, or

policies, unless they present an irreconcilable conflict with this

rule;

(2) Will not have any retroactive effect; and

(3) Will not require administrative proceedings before any parties

may file suit challenging the provisions of this rule.

Regulatory Flexibility Act Certification

RUS has determined that this rule will not have a significant

economic impact on a substantial number of small entities, as defined

by the Regulatory Flexibility Act (5 U.S.C. 601 et seq.) the RUS

programs provide and finance grants and loans to RUS borrowers at

interest rates and terms that are more favorable than those generally

available from the private sector. RUS borrowers, as a result of

obtaining Federal financing, receive economic benefits which ultimately

offset any direct economic costs associated with complying with RUS

regulations and requirements.

Information Collection and Recordkeeping Requirements

In compliance with the Office of Management and Budget (OMB)

regulations (5 CFR Part 1320) which implements the Paperwork Reduction

Act of 1980 (44 U.S.C. 3501 et seq.) and section 3504 of that Act,

information collection and recordkeeping requirements contained in this

rule have been approved by OMB under control number 0572-0059. Comments

concerning these requirements should be directed to the Office of

Information and Regulatory Affairs of OMB, Attention: Desk Officer for

USDA, Room 10102, NEOB, Washington, DC 20503.

National Environmental Policy Act Certification

The Administrator has determined that this rule will not

significantly affect the quality of the human environment as defined by

the National Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.).

Therefore, this action does not require an environmental impact

statement or assessment.

Catalog of Federal Domestic Assistance

The program described by this rule is listed in the Catalog of

Federal Domestic Assistance Programs under number 10.851, Rural

Telephone Loans and Loan Guarantees. This catalog is available on a

subscription basis from the Superintendent of Documents, the United

States Government Printing Office, Washington, DC 20402.

Executive Order 12372

This rule is excluded from the scope of Executive Order 12372,

Intergovernmental Consultation. A Notice of Final Rule entitled

Department Programs and Activities Excluded from Executive Order 12372

(50 FR 47034) exempts RUS and RTB loans and loan guarantees, and RTB

bank loans, to governmental and nongovernmental entities from coverage

under this Order.

Background

RUS makes loans and loan guarantees to telephone system to provide

and improve telecommunications service in rural areas, as authorized by

the Rural Electrification Act of 1936, as amended, 7 U.S.C. 901 et

seq., (RE Act). RUS maintains a system of construction standards and

specifications for materials and equipment. In accordance with the RUS

loan contract, these standards and specifications apply to facilities

constructed by RUS telephone borrowers.

Presently, RUS Bulletin 345-185, RUS Performance Specification for

Line Concentrators RUS Form 397g, dated July 29, 1985, is incorporated

by reference at 7 CFR 1755.97. Because of the many improvements in

technology since the specification was last issued, RUS believes that

by updating and codifying the revised specification, borrowers will be

provided with an opportunity to improve and increase subscriber

services through enhanced system designs brought about through the

technological advancements in an economical and efficient manner.

General Comments

Public comments regarding the proposed rule (59 FR 19661, April 25,

1994) were received from AT&T and Hastad Engineering Company. These

[[Page 44728]]

comments were taken into consideration in preparing the final rule.

1. Comment. One commenter stated that the first sentence in

paragraph (a)(iii) should be modified to read ``* * * without loss of

individual identity by either physical or electronic means.''

Response. The intent of this requirement is to ensure that the

identities of the lines connected to the remote line concentrator

terminal are known at the central office. RUS feels this paragraph is a

clear statement of this requirement.

2. Comment. One commenter stated that ``at a minimum'' should be

added following ``The concentrator system shall communicate with the

standard T1 transmission format'' in paragraph (b)(2).

Response. RUS agrees and this change has been made.

3. Comment. One commenter stated in the phrase ``0.5 percent per

month of all equipped cards in all system terminals after 6 months'' in

paragraph (c)(1) ``system'' should be changed to ``systems.''

Response. In this context, the word ``system'' refers to the line

concentrator system. The reliability requirement is meant to be

applicable to each concentrator system individually.

4. Comment. One commenter stated that RUS should consider

specifying a sine wave output for ringing generators in paragraph

(f)(3)(ii).

Response. A sine wave output is one of the requirements for the

acceptance of ringing generators by RUS. RUS does not feel that it is

necessary to reiterate this requirement in the line concentrator

specification.

5. Comment. One commenter stated that consideration should be given

to providing an upper limit for loop current in paragraph (h)(2).

Response. The minimum current requirement ensures proper operation

of the subscriber's station equipment. The maximum current is largely

dependent upon the design of the line concentrator's line circuit. This

specification is intended to be an operational rather than a design

specification and RUS does not feel that a maximum current requirement

is necessary in that light.

6. Comment. One commenter stated that the impedance of 900 ohms in

paragraph (h)(3) is for D66 loaded cables, not non-loaded cable pairs.

Response. From a hybrid balance standpoint, 900 ohms in series with

a 2.16 microfarad capacitor is not a very good match for either loaded

or non-loaded loops. For this reason most switching equipment uses

hybrid termination networks more closely matching the characteristic

impedances of the loops. However, as a compromise the 900 ohm

termination was used in determining transmission requirements stated in

paragraph (h)(3).

7. Comment. One commenter stated the requirement for a central

office repeater and a DS1 bit stream may be a roadblock to the

technical innovation. The STMP requirements for high bit rate services

may not be supported by the low bit rate in paragraph (h)(20)(iv)(A).

Response. RUS agrees and has removed the repeater requirement and

made the DS1 rate a minimum.

8. Comment. One commenter suggested two additions in paragraph

(j)(1)(iii)(A): (1) Require testing of equipment with 100 Hz impedances

beyond the 50 ohm maximum RUS has proposed, to a new maximum of 100

ohms, and (2) reduce the current surge test peak to 100 A from the

required 500 A but require 25 plus and minus surges instead of the plus

and minus five surges that RUS proposed.

Response. RUS evaluated the proposal by estimating the relative

overall power that would be dissipated by the 100 Hz paths under the

RUS proposal and the commenter's proposal.

Because this proposal requires additional testing of 100 Hz

impedance paths beyond the 50 ohms and because the proposer's method of

testing for overall and single surge power dissipation is less

demanding on paths less than 5 and 10 ohms and more demanding for

impedance paths greater than 5 and 10 ohms, respectively, RUS prefers

to retain the requirement as RUS proposed it.

9. Comment. One commenter proposed in paragraph (j)(1)(iii)(B) that

for 100 ohm, 60 Hz, impedance paths, using a 600 volt power supply and

86 ohm current limiting resistors (rather than the required 700 volt

power supply and 100 ohm current limiting resistors) would result in

approximately the same amount of current flow.

Response. Although not stated, RUS assumes that the commenter is

suggesting the requirement be changed to allow the different power

supply voltage and current limiting resistors. In evaluating the

circuit testing differences, RUS calculated that the commenter's

proposal would result in 4.2 amps of current while the RUS proposal

would cause 4.7 amps. Thus, the commenter's proposal results in a 0.5

amp less current. Although 0.5 amp is not a major reduction (5 percent

relative to the 10 amp maximum specified in the RUS proposal), it

nevertheless is a 5-percent reduction.

The commenter's suggested power supply voltage is also 100 volts

lower than the RUS specified supply and it will not provide the same

voltage stress that is contained in the RUS proposal.

RUS believes the Sixty Hertz Current Carrying test as proposed by

RUS is necessary to properly test the system.

10. Comment. One commenter proposed in paragraphs (j)(1)(iii) (D)

and (E) that the Voltage Impulse Test be modified to allow use of

another waveshape (both peak and rise and fall times) and that for both

the Voltage Impulse Test and the Arrester Response Delay Test that RUS

allow results obtained by other organizations as part of their

compliance testing to be acceptable for RUS compliance.

Response. RUS always attempts to accept test results conducted for

other purposes as supporting data for RUS requirements when the data

presented is equivalent or more stringent than RUS requirements.

All five tests are required to be conducted in a specific sequence

and as quickly as possible; the endeavor is to inflict all stresses,

one after another, in a very short time period for the total testing.

Testing conducted for other organizations, most likely, will not

satisfy the concerns intended for the RUS electrical protection tests.

In addition to not using the RUS specified waveshapes, tests by other

organizations usually do not involve all the individual tests in the

sequence required nor are they completed at the same time in the quick

time frame required by RUS; results of various types of testing often

may not be for tests conducted on the exact same test samples. In a

number of cases, certain tests by other organizations are expected to

destroy the product to be certain there is no fire or shock hazard.

Although RUS is certainly interested in knowing of such hazards, the

purpose of the RUS electrical protection testing is to see whether the

line concentrator can withstand the specified surges and operate

without any difficulty following the testing. Since test samples are

destroyed by these other types of tests, such product evaluations

cannot be made.

Because the test results suggested by the commenter are usually

completed piecemeal and do not provide the overall rigorous test

withstand concerns that RUS seeks, RUS cannot accept this suggestion to

allow alternative waveshapes and prefers to retain the waveshape

proposed in the proposed rule.

11. Comment. One commenter stated that RUS should provide a

standard

[[Page 44729]]

requirement for 120/240 volts AC in paragraphs (q)(2)(vii) and

(l)(2)(iii).

Response. RUS agrees and has made this change in paragraphs

(q)(2)(vii) and (l)(2)(iii).

12. Comment. One commenter stated that battery heaters as specified

in (l)(3)(iv) should not be a required item as determined by the

bidder, but should be available as an option for the purchaser to

accept or reject.

Response. RUS agrees and has changed this paragraph to read ``when

specified by the owner.''

13. Comment. One commenter stated that since line concentrators are

often installed by the purchaser, the bidder cannot provide job

drawings as required in paragraph (p)(2)(iv). The commenter also stated

that a minimum of three sets of drawings should be supplied for each

central office involved rather than for each concentrator.

Response. RUS has added an additional requirement in (p)(2)(v) when

installation is to be done by the bidder. This requirement states that

a complete set of drawings shall be provided, such as floor plans, AC

power access and grounding parameters. RUS has also stated that three

sets of drawings are required per central office rather than per

concentrator.

14. Comment. One commenter stated that an appropriate secondary

arrestor should be provided in the remote terminal cabinet.

Response. Paragraph (q)(2)(vii) requires that a secondary arrester

be provided.

15. Comment. One commenter stated the specification should include

a requirement for a remote cabinet ground lug, either on the cabinet's

outside or mounted in the interior.

Response. Paragraph (q)(2)(ix) has been changed to include ground

lugs.

List of Subjects in 7 CFR Part 1755

Incorporation by reference, Loan programs--communications,

Reporting and recordkeeping requirements, Rural areas, Telephone.

For the reasons set out in the preamble, RUS amends chapter XVII of

title 7 of the Code of Federal Regulations as set forth below.

PART 1755--TELECOMMUNICATIONS STANDARDS AND SPECIFICATIONS FOR

MATERIALS, EQUIPMENT AND CONSTRUCTION

1. The authority citation for part 1755 is revised to read as

follows:

Authority: 7 U.S.C. 901 et seq., 1921 et seq., 6941 et seq.

Sec. 1755.97 [Amended]

2. Section 1755.97 is amended by removing the entry RUS Bulletin

345-185 from the table.

3. Section 1755.397 is revised to read as follows:

Sec. 1755.397 RUS performance specification for line concentrators.

(a) General. (1) This section covers general requirements for a

line concentrator (LC) system. This system shall operate in accordance

with the manufacturer's specifications. Reliability shall be of prime

importance in the design, manufacture and installation of the

equipment. The equipment shall automatically provide for:

(i) Terminating subscriber lines at a location remote from the

serving central office;

(ii) Concentrating the subscriber lines over a few transmission and

supervisory paths to the serving central office; and

(iii) Terminating the lines at the central office without loss of

individual identity. A subscriber connected to a line concentrator

shall be capable of having essentially the same services as a

subscriber connected directly to the central office equipment (COE).

Intra-unit calling among subscribers connected to the concentrator may

be provided, but is not required.

(2) Industry standards, or portions thereof, referred to in this

paragraph (a) are incorporated by reference by RUS. This incorporation

by reference was approved by the Director of the Federal Register in

accordance with 5 U.S.C. 552 (a) and 1 CFR part 51. Copies of these

standards are available for inspection during normal business hours at

RUS, room 2838, U.S. Department of Agriculture, Washington, DC 20250 or

at the Office of the Federal Register, 800 North Capitol Street, NW.,

suite 700, Washington, DC.

(3) American National Standards Institute (ANSI) standards are

available from ANSI Inc., 11 West 42nd Street, 13th floor, New York, NY

10036, telephone 212-642-4900.

(i) ANSI Standard S1.4-1983, Specification for Sound Level Meters,

including Amendment S1.4A-1985.

(ii) [Reserved]

(4) American Society for Testing Materials (ASTM) are available

from 1916 Race Street, Philadelphia, PA 19103, telephone 215-299-5400.

(i) ASTM Specification B33-91, Standard Specifications for Tinned

Soft or Annealed Copper Wire for Electrical Purposes.

(ii) [Reserved]

(5) Bell Communications Research (Bellcore) standards are available

from Bellcore Customer Service, 8 Corporate Place, Piscataway, NJ

08854, telephone 1-800-521-2673.

(i) TR-TSY-000008, Issue 2, August 1987, Digital Interface between

the SLC 96 Digital Loop Carrier System and a Local Digital Switch.

(ii) Bell Communications Research (Bellcore) document TR-TSY-

000057, Issue 1, April 1987, including Revision 1, November 1988,

Functional Criteria for Digital Loop Carrier Systems.

(iii) Bell Communications Research (Bellcore) Document TR-NWT-

000303, Issue 2, December 1992, including Revision 1, December 1993,

Integrated Digital Loop Carrier System Generic Requirements,

Objectives, and Interface.

(6) Federal Standard H28, Screw-Thread Standards for Federal

Services, March 31, 1978, including Change Notice 1, May 28, 1986;

Change Notice 2, January 20, 1989; and Change Notice 3, March 12, 1990.

Copies may be obtained from the General Services Administration,

Specification Section, 490 East L'Enfant Plaza SW, Washington, DC

20407, telephone 202-755-0325.

(7) IEEE standards are available from IEEE Service Center, 445 Hoes

Lane, P.O. Box 1331, Piscataway, NJ 08854, telephone 1-800-521-2673.

(i) IEEE Standard 455-1985, Standard Test Procedure for Measuring

Longitudinal Balance of Telephone Equipment Operating in the Voice

Band.

(ii) [Reserved]

(8) RUS standards are available from Publications and Directives

Management Branch, Administrative Services Division, Rural Utilities

Service, room 0180, South Building, U.S. Department of Agriculture,

Washington, DC 20250-1500.

(i) RUS Bulletin 345-50, PE-60 (Sept 1979), RUS Specification for

Trunk Carrier Systems.

(ii) [Reserved]

(b) Types of requirements. (1) Unless otherwise indicated, the

requirements listed in this section are considered to be fixed

requirements.

(2) The concentrator system shall communicate with standard T1

digital transmission format at a minimum between the concentrator and

central office terminals. Analog conversion functions at remote and

central office terminals shall be capable of being eliminated to

accommodate end-to-end digital transmission.

(3) The LC shall operate properly as an integral part of the

telephone network when connected to physical or carrier derived

circuits and central offices meeting RUS specifications and other

generally accepted telecommunications practices, such as

[[Page 44730]]

Bellcore documents TR-NWT-000303, Integrated Digital Loop Carrier

System Generic Requirements, Objectives and Interface; TR-TSY-000008,

Digital Interface between the SLC 96 Digital Loop Carrier System and a

Local Digital Switch; and TR-TSY-000057, Functional Criteria for

Digital Loop Carrier Systems.

(4) For RUS acceptance consideration of a LC, the manufacturer must

certify and demonstrate that all requirements specified in this section

are available and in compliance with this section.

(5) Certain requirements are included in this section for features

which may not be needed for every application. Such features are

identifiable by the inclusion in the requirements of some such phrase

as ``when specified by the owner'' or ``as specified by the owner.'' In

some cases where an optional feature will not be required by an owner,

either now or in the future, a system which does not provide this

feature shall be considered to be in compliance with the specification

for the specific installation under consideration, but not in

compliance with the entire specification.

(6) The owner may properly request bids from any supplier of an RUS

accepted LC whose system provides all the features which will be

required for a specific installation.

(7) When required by the owner, the supplier shall state compliance

to the Carrier Serving Area (CSA) requirements, as stated in Bell

Communications Research (Bellcore) Standard TR-TSY-000057, Functional

Criteria for Digital Loop Carrier Systems.

(c) Reliability. (1) The failure rate of printed circuit boards

shall not exceed an average of 2.0 percent per month of all equipped

cards in all system terminals during the first 3 months after cutover,

and shall not exceed an average of 1.0 percent per month of all

equipped cards in all system terminals during the second 3-month

period. The failure rate for the equipment shall be less than 0.5

percent per month of all equipped cards in all system terminals after 6

months. A failure is considered to be the failure of a component on the

PC board which requires it to be repaired or replaced.

(2) The line concentrator terminal units shall be designed such

that there will be no more than 4 hours of total outages in 20 years.

(d) System type acceptance tests. General test results will be

required on each system type. Any system provided in accordance with

this section shall be capable of meeting any requirement in this

section on a spot-check basis.

(e) Features required. The network control equipment and peripheral

equipment shall be comprised of solid-state and integrated circuitry

components as far as practical and in keeping with the state-of-the-art

and economics of the subject system.

(f) Subscriber lines.--(1) General. (i) The remote LC units shall

operate satisfactorily with subscriber lines which meet all of the

conditions under the bidder's specifications and all the requirements

of this section. This section recognizes that the loop limit of the

line concentrator is dependent upon the transmission facility between

the LC central office termination and the LC remote unit. When voice

frequency (physical) circuits are used, the loop limit from the COE to

the subscriber shall be 1900 ohms (including the telephone set). When

electronically derived circuits (carrier, lightwave, etc.) are used,

the loop limits of the electronic system will control. The bidder shall

identify the loop limits of the equipment to be supplied.

(ii) There should be provisions for such types of lines as ground

start, loop start, regular subscriber, pay stations, etc.

(2) Dialing. (i) General. The line concentrator remote and central

office terminal equipment shall satisfactorily transmit dialing

information when used with subscriber dials having a speed of operation

between 8 and 12 dial pulses per second and a break period of 55 to 65%

of the total signaling period.

(ii) Subscriber dial interdigital time. The remote and central

office LC equipment shall permit satisfactory telecommunications

operation when used with subscriber rotary dial interdigital times of

200 milliseconds minimum, and pushbutton dialing with 50 milliseconds

minimum.

(iii) Subscriber line pushbutton dialing frequencies. The frequency

pairs assigned for pushbutton dialing when provided by the central

office shall be as listed in this paragraph (f)(2)(iii), with an

allowable variation of 1.5 percent:

----------------------------------------------------------------------------------------------------------------

High group frequencies (Hz)

Low group frequencies (Hz) -------------------------------------

1209 1336 1477 1633

----------------------------------------------------------------------------------------------------------------

697....................................................................... 1 2 3 Spare.

770....................................................................... 4 5 6 Spare.

852....................................................................... 7 8 9 Spare.

941....................................................................... * 0 # Spare.

----------------------------------------------------------------------------------------------------------------

(3) Ringing. (i) When LC ringing is generated at the remote end, it

shall be automatic and intermittent and shall be cut off from the

called line upon removal of the handset at the called station during

either the ringing or silent period.

(ii) When ringing generators are provided in the LC on an ancillary

basis, they shall be accepted or technically accepted by RUS.

(iii) Where ringing is generated at the remote end, the ringing

system shall provide sufficient ringing on a bridged basis over the

voltage and temperature limits of this specification and over

subscriber loops within the limits stated by the manufacturer. The

manufacturer shall state the minimum number (not less than two) of main

station ringers that can be used for each ringing option available.

(g) Traffic. (1)(i) The minimum grade of service for traffic in the

line concentrator shall be B=.005 using the Traffic Table, based on the

Erlang Lost-Calls-Cleared Formula. Required grade of service, traffic

assumptions and calculations for the particular application being

implemented shall be supplied by the bidder.

(ii) Service to customers served by a traffic sensitive LC should

not be noticeably different than the service to customers served by the

dedicated physical pairs from the central office so that uniform grade

of service will be provided to all customers in any class of service.

Reference Sec. 1755.522(p)(1)(i), RUS General Specification for

Digital, Stored Program Controlled Central Office Equipment.

(2) Traffic and Plant Registers. Traffic measurements consist of

three types--peg count, usage, and congestion. A peg count register

scores one count per call attempt per circuit group such as trunks,

digit receivers, senders, etc. Usage counters measure the traffic

density in networks, trunks and other circuit groups. Congestion

registers score the

[[Page 44731]]

number of calls which fail to find an idle circuit in a trunk group or

to find an idle path through the switching network when attempting to

connect two given end points. These conditions constitute ``network

blocking.''

(3) When required, traffic data will be stored in electronic

storage registers or a block of memory consisting of one or more

traffic counters for each item to be measured. The bidder shall

indicate what registers are to be supplied, their purpose and the means

for displaying the information locally (or at a remote location when

available).

(h) Transmission requirements. (1) General. Unless otherwise

stated, the requirements in paragraphs (h) (2) through (20) of this

section are specified in terms of analog measurements made from Main

Distributing Frame (MDF) terminals to MDF terminals excluding cabling

loss.

(2) Telephone transmitter battery supply. A minimum of 20

milliamperes, dc, shall be provided for the transmitter of the

telephone set at the subscriber station under all loop conditions

specified by the bidder. The telephone set is assumed to have a

resistance of 200 ohms.

(3) Impedance--subscriber loops. For the purpose of this section,

the input impedance of all subscriber loops served by the equipment is

arbitrarily considered to be 900 ohms in series with 2.16 microfarad

capacitor at voice frequencies.

(4) Battery noise. Noise across the remote terminal battery at

power panel distribution bus terminals shall not exceed 35 dBrnC during

the specified busy hour.

(5) Stability. The long-term allowable variation in loss through

the line concentrator system shall be 0.5 dB from the loss

specified by the bidder.

(6) Return loss. The specified return loss values are determined by

the service and type of port at the measuring end. Two-wire ports are

measured at 900 ohms in series with 2.16 microfarads, and 4-wire ports

are measured at 600 ohms resistive. When other balance networks are

supplied, test equipment arranged for operation with the supplied

network(s) may be used. The requirement given shall meet the following

cited values on each balance network available in the system:

Line-to-Line or Line-to-Trunk (2-Wire)

Echo Return Loss (ERL)--18 dB, Minimum

Singing Return Loss (SRL)--Low--15 dB, Minimum

Singing Return Loss (SRL)--High--18 dB, Minimum

(7) Longitudinal balance. The minimum longitudinal balance, with dc

loop currents between 20 to 70 mA, shall be 60 dB at all frequencies

between 60 and 2000 Hz, 55 dB at 2700 Hz and 50 dB at 3400 Hz. The

method of measurement shall be as specified in the IEEE standard 455,

``Standard Testing Procedure for Measuring Longitudinal Balance of

Telephone Equipment Operating in the Voice Band.'' Source voltage level

shall be 10 volts root mean square (rms) where conversation battery

feed originates at the remote end.

(8) 60 hz longitudinal current immunity. The LC 60 Hz longitudinal

current immunity shall be measured in accordance with Figure 1 of this

section. Under test conditions cited on Figure 1 of this section, the

system noise shall be 23 dBrnC or less as follows:

BILLING CODE 3410-15-P

[[Page 44732]]

[GRAPHIC][TIFF OMITTED]TR29AU95.002

BILLING CODE 3410-15-C

[[Page 44733]]

(9) Steady noise (idle channel at 900 ohm impedance). Steady noise:

Measure on terminated call. Noise measurements shall comply with the

following:

Maximum--23 dBrnC0

Average--18 dBrnC0 or Less

3KHz Flat--Less than 35 dBrnO as an Objective

(10) Impulse noise. LC central office terminal equipment shall have

an impulse noise limit of not more than five counts exceeding 54 dBrnC0

voice band weighted in a 5-minute period on six such measurements made

during the busy hour. A WILCOM T-194C Transmission Test Set, or

equivalent, should be used for the measurements. The measurement shall

be made by establishing a normal connection from the noise counter

through the switching equipment in its off-hook condition to a quiet

termination of 900 ohms impedance. Office battery and signaling circuit

wiring shall be suitably segregated from voice and carrier circuit

wiring, and frame talking battery filters provided, if and as required,

in order to meet these impulse noise limits.

(11) Crosstalk coupling. Worst case equal level crosstalk shall be

65 dB minimum in the range 200 to 3400 Hz. This shall be measured

between any two paths through the system by connecting a 0 dBm0 level

tone to the disturbing pair.

(12) Digital error rate. The digital line concentrator shall not

introduce more than one error in 10\8\ bits averaged over a 5-minute

period, excluding the least significant bit.

(13) Quantizing distortion. (i) The system shall meet the following

requirements:

------------------------------------------------------------------------

Minimum

signal to

distortion

Input level (dBm0) 1004 or 1020 Hz with C-

message

weighting

------------------------------------------------------------------------

0 to -30................................................. 33 dB

-30 to -40............................................... 27 dB

-40 to -45............................................... 22 dB

------------------------------------------------------------------------

(ii) Due to possible loss of the least significant bit on direct

digital connections, a signal to distortion degradation of up to 2 dB

may be allowed where adequately justified by the bidder.

(14) Overload level. The overload level shall be +3 dBm0.

(15) Gain tracking (linearity) shall meet the following

requirements:

------------------------------------------------------------------------

Maximum

Input signal level\1\ gain

deviation

------------------------------------------------------------------------

+3 to -37 dBm0............................................. 0.5 dB

-37 to -50 dBm0............................................ 1 dB

------------------------------------------------------------------------

\1\1004 Hz reference at 0 dBm0.

(16) Frequency response (loss relative to 1004 Hz) for line-to-line

(via trunk group or intra-link) connections shall meet the following

requirements:

------------------------------------------------------------------------

Frequency (Hz) Loss at 0 dBm0 input\1\

------------------------------------------------------------------------

60................................. 20 dB Min.\2\

300................................ -1 to +3 dB

600 to 2400........................ +1 dB

3400............................... -1 to +3 dB

------------------------------------------------------------------------

\1\(-) means less loss and (+) means more loss.

\2\Transmit End.

(17) Envelope delay distortion. On any properly established

connection, the envelope delay distortion shall not exceed the

following limits:

------------------------------------------------------------------------

Frequency (Hz) Microseconds

------------------------------------------------------------------------

1000 to 2600.............................................. 190

800 to 2800............................................... 350

600 to 3000............................................... 500

400 to 3200............................................... 700

------------------------------------------------------------------------

(18) Absolute delay. The absolute one-way delay through the line

concentrator, excluding delays associated with the central office

switching equipment, shall not exceed 1000 microseconds analog-to-

analog measured at 1800 Hz.

(19) Insertion loss. The insertion loss in both directions of

transmission at 1004 Hz shall be included in the insertion loss

requirements for the connected COE switch and shall not increase the

overall losses through the combined equipment beyond the values for the

COE alone, when operated through a direct digital interface. Systems

operated with a (VF) line circuit interface may introduce up to 3 dB

insertion loss. Reference Sec. 1755.522(q)(3).

(20) Detailed requirements for direct digital connections. (i) This

paragraph (h)(20) covers the detailed requirements for the provision of

interface units which will permit direct digital connection between the

host central office and line concentrator subscriber terminals over

digital facilities. The digital transmission system shall be compatible

with T1 type span lines using a DS1 interface and other digital

interfaces that may be specified by the owner. The RUS specification

for the T1 span line equipment is PE-60. Other span line techniques may

also be used. Diverse span line routing may be used when specified by

the owner.

(ii) The output of a digital-to-digital port shall be Pulse Code

Modulation (PCM), encoded in eight-bit words using the mu-255 encoding

law and D3 encoding format, and arranged to interface with a T1 span

line.

(iii) Signaling shall be by means of Multifrequency (MF) or Dual

Pulsing (DP) and the system which is inherent in the A and B bits of

the D3 format. In the case where A and B bits are not used for

signaling or system control, these bits shall only be used for normal

voice and data transmission.

(iv) When a direct digital interface between the span line and the

host central office equipment is to be implemented, the following

requirements shall be met:

(A) The span line shall be terminated in a central office as a

minimum a DS1 (1.544Mb/s) shall be provided;

(B) The digital central office equipment shall be programmed to

support the operation of the digital port with the line concentrator

subscriber terminal;

(C) The line concentrator subscriber terminal used with a direct

digital interface shall be interchangeable with the subscriber terminal

used with a central office terminal.

(i) Alarms. The system shall send alarms for such conditions as

blown fuses, blocked controls, power failure in the remote terminal,

etc., along with its own status indication and status of dry relay

contact closures or solid-state equivalent to the associated central

office alarm circuits. Sufficient system alarm points shall be provided

from the remote terminal to report conditions to the central office

alarm system. The alarms shall be transmitted from the remote terminal

to the central office terminal as long as any part of the connecting

link is available for this transmission. Fuses shall be of the alarm

and indicator type, and their rating designated by numerals or color

code on fuse positions.

(j) Electrical protection--(1) Surge protection. (i) Adequate

electrical protection of line concentrator equipment shall be included

in the design of the system. The characteristics and application of

protection devices must be such that they enable the line concentrator

equipment to withstand, without damage or excessive protector

maintenance, the dielectric stresses and currents that are produced in

line-to-ground and tip-to-ring circuits through the equipment as a

result of induced or conducted lightning or power system fault-related

surges. All wire terminals connected to outside plant wire or cable

pairs shall be protected from voltage and current surges.

[[Page 44734]]

(ii) Equipment must pass laboratory tests, simulating a hostile

electrical environment, before being placed in the field for the

purpose of obtaining field experience. For acceptance consideration RUS

requires manufacturers to submit recently completed results (within 90

days of submittal) of data obtained from the prescribed testing.

Manufacturers are expected to detail how data and tests were conducted.

There are five basic types of laboratory tests which must be applied to

exposed terminals in an effort to determine if the equipment will

survive. Figure 2 of this section, Summary of Electrical Requirements

and Tests, identifies the tests and their application as follows:

Figure 2.--Summary of Electrical Requirements and Tests

----------------------------------------------------------------------------------------------------------------

Number of

Application Peak voltage or applications and

Test criteria current Surge waveshape maximum time Comments

between

----------------------------------------------------------------------------------------------------------------

Current surge.... Low impedance 500A or lesser 10 x 1000 s. at 1 minute

surges. fig. 4). intervals.

60 Hz current High or low 10A rms or lesser 11 Cycles of 60 3 each at 1 None.

carrying. impedance paths current (see Hz (0.183 Sec.). minute intervals.

exposed to fig. 6).

surges.

AC Power service AC power service 2500V or +3 1.2 x 50 m>s. at 1 minute used, must be

clamping V of intervals. removed.

arrester Communications

employed at 10kV/ line arresters,

s. if used, remain

in place.

Voltage surge.... High impedance 1000V or +3 10 x 1000 dc m>s. at 1 minute arresters, if

surges. breakdown of intervals. used, must be

arrester removed.

employed.

Arrester response Paths protected +3 100V/s 5 each polarity All primary

delay. by arresters, breakdown of rise decay to \1/ at 1 minute arrestors, if

such as gas arrester 2\ V. in tube's intervals. used, must be

tubes, with employed at 100V/ delay time. removed.

breakdown s of

dependent on V. rise.

rate of rise.

----------------------------------------------------------------------------------------------------------------

(iii) Electrical protection requirements for line concentrator

equipment can be summarized briefly as follows:

(A) Current surge tests simulate the stress to which a relatively

low impedance path may be subjected before main frame protectors break

down. Paths with a 100 Hz impedance of 50 ohms or less shall be

subjected to current surges, employing a 10 x 1000 microsecond

waveshape as defined in Figure 3 of this section, Surge Waveshape. For

the purpose of determining this impedance, arresters which are mounted

within the equipment are to be considered zero impedance. The crest

current shall not exceed 500A; however, depending on the impedance of

the test specimen this value of current may be lower. The crest current

through the sample, multiplied by the sample's 100 Hz impedance, shall

not exceed 1000 V. Where sample impedance is less than 2 ohms, peak

current shall be limited to 500A as shown in Figure 4 of this section,

Current Surge Tests. Figures 3 and 4 follow:

BILLING CODE 3410-15-P

[[Page 44735]]

[GRAPHIC][TIFF OMITTED]TR29AU95.003

[[Page 44736]]

[GRAPHIC][TIFF OMITTED]TR29AU95.004

BILLING CODE 3410-15-C

[[Page 44737]]

(B) Sixty Hertz (60 Hz) current carrying tests shall be applied to

simulate an ac power fault which is conducted to the unit over the

cable pairs. The test shall be limited to 10 amperes Root Mean Square

(rms) of 60 Hz ac for a period of 11 cycles (0.1835 seconds) and shall

be applied longitudinally from line to ground.

(C) AC power service surge voltage tests shall be applied to the

power input terminals of ac powered devices to simulate switching

surges or lightning-induced transients on the ac power system. The test

shall employ a 1.2 x 50 microsecond waveshape with a crest voltage of

2500 V. Communications line protectors may be left in place for these

tests.

(D) Voltage surge tests which simulate the voltage stress to which

a relatively high impedance path may be subjected before primary

protectors break down and protect the circuit. To ensure coordination

with the primary protection while reducing testing to the minimum,

voltage surge tests shall be conducted at a 1000 volts with primary

arresters removed for devices protected by carbon blocks, or the +3

sigma dc breakdown voltage of other primary arresters. Surge waveshape

should be 10 x 1000 microseconds.

(E) Arrester response delay tests are designed to stress the

equipment in a manner similar to that caused by the delayed breakdown

of gap type arresters when subjected to rapidly rising voltages.

Arresters shall be removed for these tests, the peak surge voltage

shall be the +3 sigma breakdown voltage of the arrester in question on

a voltage rising at 100 V per microsecond, and the time for the surge

to decay to half voltage shall equal at least the delay time of the

tube as explained in Figure 5 of this section, Arrester Response Delay

Time as follows:

BILLING CODE 3410-15-P

[[Page 44738]]

[GRAPHIC][TIFF OMITTED]TR29AU95.005

BILLING CODE 3410-15-C

[[Page 44739]]

(iv) Tests shall be conducted in the following sequence. As not all

tests are required in every application, non-applicable tests should be

omitted:

(A) Current Impulse Test;

(B) Sixty Hertz (60 Hz) Current Carrying Tests;

(C) AC Power Service Impulse Voltage Test;

(D) Voltage Impulse Test; and

(E) Arrester Response Delay Time Test.

(v) A minimum of five applications of each polarity for the surge

tests and three for the 60 Hz Current Carrying Tests are the minimum

required. All tests shall be conducted with not more than 1 minute

between consecutive applications in each series of three or five

applications to a specific configuration so that heating effects will

be cumulative. See Figure 6 of this section, 60 Hz Current Surge Tests

as follows:

BILLING CODE 3410-15-P

[[Page 44740]]

[GRAPHIC][TIFF OMITTED]TR29AU95.006

BILLING CODE 3410-15-C

[[Page 44741]]

(vi) Tests shall be applied between each of the following terminal

combinations for all line operating conditions:

(A) Line tip to ring;

(B) Line ring to ground;

(C) Line tip to ground; and

(D) Line tip and ring tied together to ground.

(2) Dielectric strength. (i) Arresters shall be removed for all

dielectric strength tests.

(ii) Direct current potentials shall be applied between all line

terminals and the equipment chassis and between these terminals and

grounded equipment housings in all instances where the circuitry is dc

open circuit from the chassis, or connected to the chassis through a

capacitor. The duration of all dielectric strength tests shall be at

least 1 second. The applied potential shall be at a minimum equal to

the plus 3 sigma dc breakdown voltage of the arrester, provided by the

line concentrator manufacturer.

(3) Insulation resistance. Following the dielectric tests, the

insulation resistance of the installed electrical circuits between

wires and ground, with the normal equipment grounds removed, shall not

be less than 10 megohms at 500 volts dc at a temperature of 68 deg.F

(20 deg.C) and at a relative humidity of approximately 50 percent. The

measurement shall be made after the meter stabilizes, unless the

requirement is met sooner. Arresters shall be removed for these tests.

(4) Self-protection. (i) All components shall be capable of being

continuously energized at rated voltage without injury. Design

precautions must be taken to prevent damage to other equipment

components when a particular component fails.

(ii) Printed circuit boards or similar equipment employing

electronic components should be self-protecting against external

grounds applied to the connector terminals. Board components and

coatings applied to finished products shall be of such material or so

treated that they will not support combustion.

(iii) Every precaution shall be taken to protect electrostatically

sensitive components from damage during handling. This shall include

written instructions and recommendations.

(k) Miscellaneous--(1) Interconnect wire. All interconnect wire

shall be of soft annealed tinned copper wire meeting the requirements

of ASTM Specification B33-91 and of suitable cross-section to provide

safe current carrying capacity and mechanical strength. The insulation

of installed wire, connected to its equipment and frames, shall be

capable of withstanding the same insulation resistance and dielectric

strength requirements as given in paragraphs (j)(2) and (j)(3) of this

section at a temperature of 120 deg.F (49 deg.C), and a relative

humidity of 90 percent.

(2) Wire wrapped terminals. These terminals are preferred and where

used shall be of a material suitable for wire wrapping. The connections

to them shall be made with a wire wrapping tool with the following

minimum number of successive non-overlapping turns of bare tinned

copper wire in contact with each terminal:

(i) 6 turns of 30 gauge;

(ii) 6 turns of 26 gauge;

(iii) 6 turns of 24 gauge; or

(iv) 5 turns of 22 gauge.

(3) Protection against corrosion. All metal parts of equipment

frames, distributing frames, cable supporting framework and other

exposed metal parts shall be constructed of corrosion resistant

materials or materials plated or painted to render them adequately

corrosion resistant.

(4) Screws and bolts. Screw threads for all threaded securing

devices shall be of American National Standard form in accordance with

Federal Standard H28, unless exceptions are granted to the manufacturer

of the switching equipment. All bolts, nuts, screws, and washers shall

be of nickel-copper alloy, steel, brass or bronze.

(5) Environmental requirements. (i) The bidder shall specify the

environmental conditions necessary for safe storage and satisfactory

operation of the equipment being bid. If requested, the bidder shall

assist the owner in planning how to provide the necessary environment

for the equipment.

(ii) To the extent practicable, the following temperature range

objectives shall be met:

(A) For equipment mounted in central office and subscriber

buildings, the carrier equipment shall operate satisfactory within an

ambient temperature range of 32 deg.F to 120 deg.F (0 deg.C to 49

deg.C) and at 80 percent relative humidity between 50 deg.F and 100

deg.F (10 deg.C and 38 deg.C); and

(B) Equipment mounted outdoors in normal operation (with cabinet

doors closed) shall operate satisfactorily within an ambient

temperature range (external to cabinet) of -40 deg.F to 140 deg.F

(-40 deg.C to 60 deg.C) and at 95 percent relative humidity between

50 deg.F to 100 deg.F (10 deg.C to 38 deg.C). As an alternative to

the (60 deg.C) requirement, a maximum ambient temperature of 120

deg.F (49 deg.C) with equipment (cabinet) exposed to direct sunlight

may be substituted.

(6) Stenciling. Equipment units and terminal jacks shall be

adequately designated and numbered. They shall be stenciled so that

identification of equipment units and leads for testing or traffic

analysis can be made without unnecessary reference to prints or

descriptive literature.

(7) Quantity of equipment bays. Consistent with system arrangements

and ease of maintenance, space shall be provided on the floor plan for

an orderly layout of future equipment bays. Readily accessible

terminals will be provided for connection to interbay and frame cables

to future bays. All cables, interbay and intrabay (excluding power), if

technically feasible, shall be terminated at both ends by connectors.

(8) Radio and television interference. Measures shall be employed

by the bidders to limit the radiation of radio frequencies generated by

the equipment so as not to interfere with radio, television receivers,

or other sensitive equipment.

(9) Housing. (i) When housed in a building supplied by the owner, a

complete floor plan including ceiling height, floor loading, power

outlets, cable entrances, equipment entry and travel, type of

construction, and other pertinent information shall be supplied.

(ii) In order to limit corrosion, all metal parts of the housing

and mounting frames shall be constructed of suitable corrosion

resistant materials or materials protectively coated to render them

adequately resistant to corrosion under the climatic and atmospheric

conditions existing in the area in which the housing is to be

installed.

(10) Distributing frame. (i) The line concentrator terminal

equipment located at the central office shall be protected by the

central office main distribution frame. The bidder may supply

additional protection capability as appropriate. All protection devices

(new or existing) shall be arranged to operate in a coordinated manner

to protect equipment, limit surge currents, and protect personnel.

(ii) The distributing frame shall provide terminals for terminating

all incoming cable pairs. Arresters shall be provided for all incoming

cable pairs, or for a smaller number of pairs if specified.

(iii) The current carrying capacity of each arrester and its

associated mounting shall coordinate with a #22 gauge copper conductor

without causing a self-sustaining fire or permanently damaging other

arrester positions. Where all cable pairs entering the housing are #24

gauge or finer, the arresters and mountings need only

[[Page 44742]]

coordinate with #24 gauge cable conductors.

(iv) Remote terminal protectors may be mounted and arranged so that

outside cable pairs may be terminated on the left or bottom side of

protectors (when facing the vertical side of the MDF) or on the back

surface of the protectors. Means for easy identification of pairs shall

be provided.

(v) Protectors shall have a ``dead front'' (either insulated or

grounded) where live metal parts are not readily accessible.

(vi) Protectors shall be provided with an accessible terminal of

each incoming conductor which is suitable for the attachment of a

temporary test lead. They shall also be constructed so that auxiliary

test fixtures may be applied to open and test the subscriber's circuit

in either direction. Terminals shall be suitable for wire wrapped

connections or connectorized.

(vii) If specified, each protector group shall be furnished with a

factory assembled tip cable for splicing to the outside cable; the tip

cable shall be 20 feet (6.1 m) in length, unless otherwise specified.

Tip cable used shall be RUS accepted.

(viii) Protector makes and types used shall be RUS accepted.

(l) Power equipment--(1) General. When specified, batteries and

charging equipment shall be supplied for the remote terminal of the

line concentrator.

(2) Operating voltage. (i) The nominal operating voltage of the

central office and remote terminal shall be 48 volts dc, provided by a

battery with the positive side tied to system ground.

(ii) Where equipment is dc powered, it must operate satisfactorily

over a range of 50 volts 6 volts dc.

(iii) Where equipment is ac powered, it must operate satisfactorily

over a range of 12010 volts or 22010 volts ac.

(3) Batteries. (i) Unless otherwise specified by the owner, sealed

batteries shall be supplied for the remote line concentrator terminal.

(ii) The batteries shall have an ampere hour load capacity of no

less than 8 busy hours. When an emergency ac supply source is

available, the battery reserve may be reduced to 3 busy hours.

(iii) The batteries shall be sealed when they are mounted in the

cabinet with the concentrator equipment.

(iv) When specified by the owner, battery heaters shall be supplied

in a bidder-furnished housing.

(4) Charging equipment. (i) One charger capable of carrying the

full dc power load of the remote terminal shall be supplied unless

otherwise specified by the owner.

(ii) Charging shall be on a full float basis. The rectifiers shall

be of the full wave, self-regulating, constant voltage, solid-state

type and shall be capable of being turned on and off manually.

(iii) When charging batteries, the voltage at the battery terminals

shall be adjustable and shall be set at the value recommended for the

particular battery being charged, provided it is not above the maximum

operating voltage of the central office switching equipment. The

voltage shall not vary more than 0.02 volt dc per cell

between 10% load and 100% load. Between 3% and 10% load, the output

voltage shall not vary more than 0.04 volt dc per cell.

Beyond full load current the output voltage shall drop sharply. The

above output voltage shall be maintained with input line voltage

variations of plus or minus 10 percent. Provision shall be made to

manually change the output voltage of the rectifier to 2.25 volts per

cell to provide an equalization charge on the battery.

(iv) The charger noise, when measured with a suitable noise

measuring set and under the rated battery capacitance and load

conditions, shall not exceed 22 dBrnC. See Figure 7 of this section,

Charger Noise Test as follows:

BILLING CODE 3410-15-P

[[Page 44743]]

[GRAPHIC][TIFF OMITTED]TR29AU95.007

BILLING CODE 3410-15-C

[[Page 44744]]

(v) The charging equipment shall be provided with a means for

indicating a failure of charging current whether due to ac power

failure, an internal failure in the charger, or to other circumstances

which might cause the output voltage of the charger to drop below the

battery voltage. Where a supplementary constant current charger is

used, an alarm shall be provided to indicate a failure of the charger.

(vi) Audible noise developed by the charging equipment shall be

kept to a minimum. Acoustic noise resulting from operation of the

rectifier shall be expressed in terms of dB indicated on a sound level

meter conforming to American National Standards Institute S1.4, and

shall not exceed 65 dB (A-weighting) measured at any point 5 feet

(1.5m) from any vertical surface of the rectifier.

(vii) The charging equipment shall be designed so that neither the

charger nor the central office equipment is subject to damage in case

the battery circuit is opened for any value of load within the normal

limits.

(5) Power panel. (i) Battery and charger control switches, dc

voltmeters, dc ammeters, fuses and circuit breakers, supervisory and

timer circuits shall be provided as required. Portable or panel mounted

frequency meters or voltmeters shall be provided as specified by the

owner.

(ii) Power panels, cabinets and shelves, and associated wiring

shall be designed initially to handle the line concentrator terminal

when it reaches its ultimate capacity as specified by the owner.

(iii) The power panel shall be of the ``dead front'' type.

(6) Ringing equipment. The ringing system shall provide sufficient

ringing on a bridged basis over the voltage and temperature limits of

this section and over subscriber drops within the limits stated by the

bidder. The ringing system shall be without operational problems such

as bell tapping during dialing. The bidder shall state the minimum

number (not less than two) of main station ringers that can be used for

each ringing option available.

(7) Interrupter equipment. The interrupter may be an integral part

of the system or may be part of the associated central office equipment

connected to the line concentrator central office terminal.

(8) Special systems. Manufacturers of LC systems that operate by

extending ringing current from the central office shall state their

required input ringing (voltage and frequency) and the limitations on

the connected subscriber loop.

(m) Fusing requirements--(1) General. (i) The equipment shall be

completely wired and equipped with fuses, trouble signals, and all

associated equipment for the wire capacity of the frames or cabinets

provided.

(ii) Design precautions shall be taken to prevent the possibility

of equipment damage arising from the insertion of an electronic package

into the wrong connector or the removal of a package from any connector

or improper insertion of the correct card in its connector.

(2) Fuses. Fuses and circuit breakers shall be of an alarm and

indicator type, except where the fuse or breaker location is indicated

on the alarm printout. Their rating shall be designated by numerals or

color codes on the fuse or the panel.

(n) Trouble location and test--(1) Equipment. (i) Trouble

indications in the system may be displayed in the form of lights on the

equipment units or printed circuit boards.

(ii) When required, a jack or other connector shall be provided to

connect a fault or trouble recorder (printer or display).

(2) Maintenance system. (i) The maintenance system shall monitor

and maintain the system operation without interruption of call

processing except for major failures.

(ii) The maintenance system shall be arranged to provide the

ability to determine trouble to an individual card, functional group of

cards, or other equipment unit.

(o) Spare parts. Lists of spare parts and maintenance tools as

recommended by the bidder shall be provided. The cost of such tools and

spare parts shall be indicated and shall not be included in the base

price.

(p) Drawings and printed material. (1) The bidder shall supply

instructional material for each line concentrator system involved at

the time of delivery of the equipment. It is not the intent of this

section to require system documentation necessary for the repair of

individual circuit boards.

(2) Three complete sets of legible drawings shall be provided for

each central office to be accessed. Each set shall include all of the

following:

(i) Drawings of major equipment items such as frames, with the

location of major component items of equipment shown therein;

(ii) Wiring diagrams indicating the specific method of wiring used

on each item of equipment and interconnection wiring between items of

equipment;

(iii) Maintenace drawings covering each equipment item that

contains replaceable parts, appropriately identifying each part by name

and part number; and

(iv) Job drawings including all drawings that are individual to the

particular line concentrator involved such as mainframe, power

equipment, etc.

(3) The following information shall also be furnished:

(i) A complete index of required drawings;

(ii) An explanation of electrical principles of operation of

overall concentrator system;

(iii) A list of tests which can be made with each piece of test

equipment furnished and an explanation of the method of making each

test;

(iv) A sample of each form recommended for use in keeping records;

(v) The criteria for analyzing results of tests and determining

appropriate corrective action;

(vi) A set of general notes on methods of isolating equipment

faults to specific printed circuit cards in the equipment;

(vii) A list of typical troubles which might be encountered,

together with general indications as to probable location of each

trouble; and

(viii) All special line concentrator system grounding requirements.

(4) When installation is to be done by the bidder a complete set of

drawings shall be provided by the owner, such as floor plans, lighting,

grounding and ac power access.

(q) Installation and acceptance.--(1) General. Paragraphs (q)(2)(i)

through (q)(3)(xxi) of this section covers the general requirements for

the installation of line concentrator equipment by the bidder, and

outlines the general conditions to be met by the owner in connection

with such installation work. The responsibilities apply in both the

central office installation and remote terminal installations, unless

otherwise noted.

(2) Responsibilities of owner. The owner shall:

(i) Allow the bidder and its employees free access to the premises

and facilities at all hours during the progress of the installation;

(ii) Provide access to the remote site and any other site for

development work needed during the installation;

(iii) Take such action as necessary to ensure that the premises are

dry and free from dust and in such condition as not to be hazardous to

the installation personnel or the material to be installed (not

required when remote terminal is not installed in a building);

(iv) Provide heat or air conditioning when required and general

illumination in rooms in which work is to be performed or materials

stored;

[[Page 44745]]

(v) Provide suitable openings in buildings to allow material to be

placed in position (not required when a remote terminal is not

installed in a building);

(vi) Provide the necessary conduit and commercial and dc-ac

inverter output power to the locations shown on the approved floor plan

drawings;

(vii) Provide 110 volts a.c., 60 Hz commercial power equipped with

a secondary arrester and a reasonable number of outlets for test,

maintenance and installation equipment;

(viii) Provide suitable openings or channels and ducts for cables

and conductors from floor to floor and from room to room;

(ix) Provide suitable ground leads, as designated by the bidder

(not required when remote terminal is not installed in a building);

(x) Provide the necessary wiring, central office ground and

commercial power service, with a secondary arrester, to the location of

an exterior remote terminal installation based on the voltage and load

requirements furnished voltage and load requirements furnished by the

bidder;

(xi) Test at the owners expense all lines and trunks for

continuity, leakage and loop resistance and ensure that all lines and

trunks are suitable for operation with the central office and remote

terminal equipment specified;

(xii) Make alterations and repairs to buildings necessary for

proper installation of material, except to repair damage for which the

bidder or its employees are responsible;

(xiii) Connect outside cable pairs on the distributing frame (those

connected to protectors);

(xiv) Furnish all line, class of service assignment, and party line

assignment information to permit bidder to program the data base memory

within a reasonable time prior to final testing;

(xv) Release for the bidder's use, as soon as possible, such

portions of the existing plant as are necessary for the proper

completion of such tests as require coordination with existing

facilities including facilities for T1 span lines with properly

installed repeaters between the central office and the remote terminal

installations;

(xvi) Make prompt inspections as it deems necessary when notified

by the bidder that the equipment, or any part thereof, is ready for

acceptance;

(xvii) Provide adequate fire protection apparatus at the remote

terminal, including one or more fire extinguishers or fire

extinguishing systems of the gaseous type, that has low toxicity and

effect on equipment;

(xviii) Provide necessary access ports for cable, if underfloor

cabling is selected;

(xix) Install equipment and accessory plant devices mounted

external to the central office building and external to the repeater

and other outside housings including filters, repeater housings,

splicing of repeater cable stubs, externally mounted protective devices

and other such accessory devices in accordance with written

instructions provided by the bidder; and

(xx) Make all cross connections (at the MDF or Intermediate

Distribution Frame IDF) between the physical trunk or carrier equipment

and the central office equipment unless otherwise specified in appendix

A of this section.

(3) Responsibilities of bidder. The bidder shall:

(i) Allow the owner and its representatives access to all parts of

the building at all times;

(ii) Obtain the owner's permission before proceeding with any work

necessitating cutting into or through any part of the building

structure such as girders, beams, concrete or tile floors, partitions

or ceilings (does not apply to the installation of lag screws,

expansion bolts, and similar devices used for fastening equipment to

floors, columns, walls, and ceilings);

(iii) Be responsible for and repair all damage to the building due

to carelessness of the bidder's workforce, exercise reasonable care to

avoid any damage to the owner's switching equipment or other property,

and report to the owner any damage to the building which may exist or

may occur during its occupancy of the building;

(iv) Consult with the owner before cutting into or through any part

of the building structure in all cases where the fireproofing or

moisture proofing may be impaired;

(v) Take necessary steps to ensure that all fire fighting apparatus

is accessible at all times and all flammable materials are kept in

suitable places outside the building;

(vi) Not use gasoline, benzene, alcohol, naphtha, carbon

tetrachloride or turpentine for cleaning any part of the equipment;

(vii) Be responsible for delivering the CO and remote terminal

equipment to the sites where they will be needed;

(viii) Install the equipment in accordance with the specifications

for the line concentrator;

(ix) Have all leads brought out to terminal blocks on the MDF (or

IDF if stated in appendix A of this section) and have all terminal

blocks identified and permanently labeled;

(x) Use separate shielded type leads grounded at one end only

unless otherwise specified by the owner or bidder or tip cables meeting

RUS cable crosstalk requirements for carrier frequencies inside the

central office;

(xi) Group the cables to separate carrier frequency, voice

frequency, signaling, and power leads;

(xii) Make the necessary power and ground connections (location as

shown in appendix A of this section) to the purchaser's power terminals

and ground bus unless otherwise stated in appendix A of this section

(ground wire shall be 6 AWG unless otherwise stated);

(xiii) Place the battery in service in compliance with the

recommendations of the battery manufacturer;

(xiv) Make final charger adjustments using the manufacturer's

recommended procedure;

(xv) Run all jumpers, except line and trunk jumpers (those

connected to protectors) unless otherwise specified in appendix A of

this section;

(xvi) Establish and update all data base memories with subscriber

information as supplied by the owner until an agreed turnover time;

(xvii) Give the owner notice of completion of the installation at

least one week prior to completion;

(xviii) Permit the owner or its representative to conduct tests and

inspections after installation has been completed in order that the

owner may be assured the requirements for installation are met;

(xix) Allow access, before turnover, by the owner or its

representative, upon request, to the test equipment which is to be

turned over as a part of the delivered equipment, to permit the

checking of the circuit features which are being tested and to permit

the checking of the amount of connected equipment to which the test

circuits have access;

(xx) Notify the owner promptly of the completion of work of the

central office terminals, remote terminals or such portions thereof as

are ready for inspection; and

(xxi) Correct promptly all defects for which the bidder is

responsible.

(4) Information to be furnished by bidder. The bidder shall

accompany its bid with the following information:

(i) Two copies of the equipment list and the traffic calculations

from which the quantities in the equipment list are determined;

(ii) Two copies of the traffic tables from which the quantities are

determined, if other than the Erlang B traffic tables;

(iii) A block diagram of the line concentrator and associated

[[Page 44746]]

maintenance equipment will be provided;

(iv) A prescribed method and criteria for acceptance of the

completed line concentrator which will be subject to review;

(v) This special grounding requirements including the recommended

configuration, suggested equipment and installation methods to be used

to accomplish them;

(vi) The special handling and equipment requirements to avoid

damage resulting from the discharge of static electricity (see

paragraph (j) (4) (iii) of this section) or mechanical damage during

transit installation and testing;

(vii) The location of technical assistance service, its

availability and conditions for owner use and charges for the service

by the bidder; and

(viii) The identification of the subscriber loop limits available

beyond the line concentrator.

(5) Installation requirements. (i) All work shall be done in a

neat, workmanlike manner. Equipment frames or cabinets shall be

correctly located, carefully aligned, anchored, and firmly braced.

Cables shall be carefully laid with sufficient radius of curvature and

protected at corners and bends to ensure against damage from handling

or vibration. Exterior cabinet installations for remote terminals shall

be made in a permanent, eye-pleasing manner.

(ii) All multiple and associated wiring shall be continuous, free

from crosses, reverses, and grounds and shall be correctly wired at all

points.

(iii) An inspection shall be made by the owner or its

representatives prior to performing operational and performance tests

on the equipment, but after all installing operations which might

disturb apparatus adjustments have been completed. The inspection shall

be of such character and extent as to disclose with reasonable

certainty any unsatisfactory condition of apparatus or equipment.

During these inspections, or inspections for apparatus adjustments, or

wire connections, or in testing of equipment, a sufficiently detailed

examination shall be made throughout the portion of the equipment

within which such condition is observed, or is likely to occur, to

disclose the full extent of its existence, where any of the following

conditions are observed:

(A) Apparatus or equipment units failing to compare in quantity and

type to that specified for the installation;

(B) Apparatus or equipment units damaged or incomplete;

(C) Apparatus or equipment affected by rust, corrosion or marred

finish; and

(D) Other adverse conditions resulting from failure to meet

generally accepted standards of good workmanship.

(6) Operational tests. (i) Operational tests shall be performed on

all circuits and circuit components to ensure their proper functioning

in accordance with appropriate explanation of the operation of the

circuit.

(ii) All equipment shall be tested to ensure proper operation with

all components connected in all possible combinations and each line

shall be tested for proper ring, ring trip and supervision.

(iii) All fuses shall be verified for continuity and correct

rating. Alarm indication shall be demonstrated for each equipped fuse

position. An already failed fuse compatible with the fuse position may

be used.

(iv) Each alarm or signal circuit shall be checked for correct

operation.

(v) A sufficient quantity of locally originating and incoming calls

shall be made to demonstrate the function of the line concentrator

including all equipped transmission paths. When intra-link calling is

supplied, all intra-link transmission paths shall be demonstrated.

(7) Acceptance tests and data required. (i) Data shall be supplied

to the owner by the bidder in writing as a part of the final documents

in closing out the contract as follows:

(A) A detailed cross connect drawing of alarm to power board,

central office battery to physical trunks or carrier system, wiring

options used in terminals, channels, filters, repeaters, etc., marked

in the owner's copy of the equipment manual or supplied separately;

(B) The measured central office supply voltages applied to the

equipment terminals or repeaters at the time the jack and test point

readings are made and ac supply voltages where equipment is powered

from commercial ac sources;

(C) A list of all instruments, including accessories, by

manufacturer and type number, used to obtain the data; and

(D) The measurements at all jack or test points recommended by the

manufacturer, including carrier frequency level measurements at all

carrier terminals and repeaters where utilized.

(ii) Data in the form of a checklist or other notations shall be

supplied showing the results of the operational tests.

(iii) The bidder shall furnish to the owner a record of the battery

cell or multicell unit voltages measured at the completion of the

installation of the switching system before it is placed in commercial

service. This is not required at a site where the owner furnishes dc

power.

(8) Joint inspection requirements. (i) The bidder shall notify the

owner in writing at least one week before the date the complete system

will be ready for inspection and tests. A joint inspection shall be

made by the bidder and the owner (or owner's engineer) to determine

that the equipment installation is acceptable. The inspection shall

include physical inspection, a review of acceptance test data,

operational tests, and sample measurements.

(A) The owner shall review the acceptance test data and compare it

to the requirements of this section.

(B) Sample measurements shall be made on all systems installed

under this contract. Test methods should follow procedures described in

paragraph (g)(5) of this section.

(C) A check shall be made of measured test point and jack readings

for compliance with the manufacturer's specifications. This applies

also to channels, terminals, carrier frequency repeaters, and fault

locating circuits.

(ii) In the event that the measured data or operational tests show

that equipment fails to meet the requirements of this section, the

deficiencies are to be resolved as set forth in Article II of the 397

Special Equipment Contract. (Copies are available from RUS, room 0174,

U.S. Department of Agriculture, Washington, DC 20250-1500.) The reports

of the bidder and the owner shall be detailed as to deficiencies,

causes, corrective action necessary, corrective action to be taken,

completion time, etc.

(The information and recordkeeping requirements of this section have

been approved by the Office of Management and Budget (OMB) under the

control number 0572-0059.)

Appendix A to Sec. 1755.397--Specification for Line Concentrator

Detailed Equipment Requirements

(Information To Be Supplied by Owner)

Telephone Company (Owner)

Name:------------------------------------------------------------------

Location:--------------------------------------------------------------

Number of LC's Required: ________

Line Concentrator Locations:

------------------------------------------------------------------------

No. of Central

Location Lines Office

------------------------------------------------------------------------

........... ...........

........... ...........

........... ...........

........... ...........

------------------------------------------------------------------------

[[Page 44747]]

1. General

1.1 Notwithstanding the bidder's equipment lists, the equipment

and materials furnished by the bidder must meet the requirements of

paragraphs (a) through (p) of this section, and this appendix A.

1.2 Paragraph (a) through (p) of this section cover the minimum

general requirements for line concentrator equipment.

1.3 Paragraph (q) of this section covers the requirements for

installation, inspection and testing when such service is included

as part of the contract.

1.4 This appendix A covers the technical data for application

engineering and detailed equipment requirements insofar as they can

be established by the owner. This appendix A shall be filled in by

the owner.

1.5 Appendix B of this section covers detailed information on

the line concentrator equipment, information on system reliability

and traffic capacity as proposed by the bidder. Appendix B of this

section is to be filled in by the bidder and must be presented with

the bid.

Office Name

(By Location)----------------------------------------------------------

LC Designation---------------------------------------------------------

2. Number of Subscriber Lines

------------------------------------------------------------------------

Wired

Equipped only

------------------------------------------------------------------------

Single-Party........................................ ........ ........

Pay Station (Type:________)......................... ........ ........

Other (Describe:________)........................... ........ ........

Total......................................... ........ ........

------------------------------------------------------------------------

3. Loop Resistance

3.1 Number of non-pay station lines having a loop resistance,

including the telephone set as follows:

3.1.1 For physical trunks between the remote and the office

units, the loop resistance is to include the resistance of the

trunk.

------------------------------------------------------------------------

No. of

lines

------------------------------------------------------------------------

1200-1900 ohms............................................. ...........

1901-3200 ohms............................................. ...........

3201-4500 ohms............................................. ...........

------------------------------------------------------------------------

3.1.2 Number of pay station lines having a loop resistance,

excluding the telephone set, greater than:

------------------------------------------------------------------------

No. of

lines

------------------------------------------------------------------------

1200 ohms (Prepay)......................................... ...........

1000 ohms (Semi-Postpay)................................... ...........

------------------------------------------------------------------------

When physical trunks are used, these resistances include that of

the facility between the CO and the remote.

3.1.3 Range extension equipment, if required, is to be

provided:

________ By Bidder

________ By Owner

(Quantity and Type)----------------------------------------------------

----------------------------------------------------------------------

4. Traffic Data

4.1 Average combined originating and terminating hundred call

seconds (CCS) per line in the busy hour:

______ CCS/Line. (Assume originating & terminating equal.)

4.2 Percent Intra-Calling ________

4.3 Total Busy Hour Calls ________

5. TYPE or RINGING

5.1 Frequency No. 1. 2. 3. 4.

Frequency (Hz).......................... ...... ...... ...... ......

Max. No. of Phones/Freq................. ...... ...... ...... ......

5.2 Minimum ringing generator capacity to be supplied shall be

sufficient to serve ________ lines (each frequency).

6. Central Office Equipment Interface

6.1 COE will be:

6.1.1 COE Manufacturer

----------------------------------------------------------------------

Type-------------------------------------------------------------------

Year-------------------------------------------------------------------

Generic----------------------------------------------------------------

6.1.2 ________ See digital central office specification for the

switchboard at ____________________ .

6.2 Interface will be:

6.2.1 ________ Line Circuit(s)

6.2.2 ________ Direct Digital Interface

6.2.3 ________ Other (Describe)

----------------------------------------------------------------------

----------------------------------------------------------------------

6.3 Mounting rack for line concentrator furnished by:

________ Bidder

________ Owner

(Specify width and height of rack available) (Width) (Height)

6.4 Equipment to be installed in existing building:

________ Yes (Attach detailed plan)

________ No

7. Transmission Facilities

7.1 Transmission facilities between the central office and

remote terminals shall be:

7.1.1 Type:

________VF Carrier Derived Circuits

________Digital Span Line (DS1)

________Other

----------------------------------------------------------------------

(Attach a layout of the transmission facilities between the central

office and the remote terminals describing transmission and

signaling parameters, routing and resistance where applicable.)

7.1.2 Utilizes physical plant

________Cable Pairs (Existing/New)

________Other

----------------------------------------------------------------------

Note: Unless otherwise stated, physical plant will be supplied

by the owner.

7.1.3 Terminal equipment for transmission facility to be

supplied by:

________Owner

________Bidder

7.1.3.1 Carrier e/w voice terminations ________ Yes ________ No

Manufacturer and type--------------------------------------------------

Central office voice terminations Equipped ________, Wired Only

________

7.1.3.2 Digital span line (DS1) supplied by

________Owner

________Bidder

Manufacturer and Type--------------------------------------------------

7.1.3.3 Number of repeaters (per span line) ________

7.1.3.4 Diverse (alternate) span line routing required

________Yes (Describe in Item 11) ________No

7.1.3.5 Span line terminations only ________Yes ________No

7.1.3.6 Span line power required (CO and Remote Terminals)

________Yes ________No

7.1.3.7 Physical facility between CO and remote Loop Resistance

________ohms, Length ________meters

8. Power Equipment Requirements

8.1 Central Office Terminal

8.1.1 Owner-furnished -48 volt dc power ________Yes ________No

8.1.2 Other (Describe)

----------------------------------------------------------------------

8.1.3 Standby power is available ________Yes ________No

8.2 Remote Terminal

8.2.1 Owner-furnished -48 vdc power ________Yes ________No

8.2.2 Bidder-furnished power supply ________Yes ________No

8.2.3 AC power available at site:

________110 vac, 60 Hz, single-phase

________Other (Describe in Item 11)

8.2.4 A battery reserve of ________ busy hours shall be

provided for this line concentrator terminal when it reaches

________ lines at the traffic rates specified.

8.2.5 Batteries supplied shall be:

________Lead Calcium

________Stabilized Electrolyte

________Sealed Lead Acid

________Other (Describe in item 11)

8.2.6 Standby power is available ________Yes ________No

9. Remote Terminal

9.1 Mounting

9.1.1 ________Outside Housing (To be furnished by bidder)

9.1.2 ________Concrete Slab to be furnished by owner (Bidder to

supply construction details after award.)

9.1.3 ________Manhole, environmentally controlled (Describe in

Item 11)

9.1.4 ________Pedestal Mounting

9.1.5 ________Pole Mounting (Owner-furnished installed pole)

9.1.6 ________Prefab Building (Owner-furnished site)

9.2 Equipment is to be installed in an existing building.

________Yes ________No

(Attach detailed plan.)

[[Page 44748]]

9.3 Other (Describe)

----------------------------------------------------------------------

----------------------------------------------------------------------

10. Alternates

11. Explanatory Notes

Appendix B to Sec. 1755.397--Specification for Line Concentrators

Detailed Requirements; Bidder Supplied Information

Telephone Company (Owner)

Name:------------------------------------------------------------------

Location:--------------------------------------------------------------

Line Concentrator Equipment Locations

Central Office Terminal:-----------------------------------------------

Remote Terminal:-------------------------------------------------------

1. General

1.1 The equipment and materials furnished by the bidder must

meet the requirements of paragraphs (a) through (p) of this section.

1.2 Paragraph (a) through (p) of this section cover the minimum

general requirements for line concentrator equipment.

1.3 Paragraph (q) of this section covers requirements for

installation, inspection and testing when such service is included

as part of the contract.

1.4 Appendix A of this section covers the technical data for

application engineering and detailed equipment requirements insofar

as they can be established by the owner. Appendix A of this section

is to be filled in by the owner.

1.5 This appendix B covers detailed information on the line

concentrator equipment, information as to system reliability and

traffic capacity as proposed by the bidder. This appendix B shall be

filled in by the bidder and must be presented with the bid.

2. Performance Objectives

2.1 Reliability (See paragraph (c) of this section)

----------------------------------------------------------------------

----------------------------------------------------------------------

----------------------------------------------------------------------

----------------------------------------------------------------------

2.2 Busy Hour Load Capacity and Traffic Delay (See Paragraph

(g) of this section)

----------------------------------------------------------------------

----------------------------------------------------------------------

----------------------------------------------------------------------

3. Equipment Quantities Dependent on System Design

3.1 Transmission Facilities between the Central Office and

Remote Terminals

------------------------------------------------------------------------

Quantity Quantity

Type equipped wired only

------------------------------------------------------------------------

........... ...........

........... ...........

........... ...........

------------------------------------------------------------------------

4. Power Requirements

4.1 Central Office Terminal

Voltage----------------------------------------------------------------

Current Drain (Amps) Normal ________, Peak ________

Fuse Qty ________, Size ________, Type ________

Heat Dissipation (BTU/Hr.) ________

----------------------------------------------------------------------

4.2 Remote Terminal

AC or DC---------------------------------------------------------------

Voltage----------------------------------------------------------------

Current Drain (Amps) Normal ________, Peak ________

Fuse Qty ________, Size ________, Type ________

Heat Dissipation (BTU/Hr.) ________

----------------------------------------------------------------------

Power required for heating or cooling equipment in remote

bidder-furnished housing

----------------------------------------------------------------------

----------------------------------------------------------------------

5. Temperature and Humidity Limitations

5.1 Temperature

------------------------------------------------------------------------

Central

office Remote*

------------------------------------------------------------------------

Maximum deg.F ( deg.C)....................... ........... ...........

Minimum deg.F ( deg.C)....................... ........... ...........

------------------------------------------------------------------------

5.2 Relative Humidity

------------------------------------------------------------------------

Central

office Remote*

------------------------------------------------------------------------

Maximum....................................... ........... ...........

Minimum....................................... ........... ...........

------------------------------------------------------------------------

*Show conditions outside bidder-furnished housing.

6. Explanatory Notes

Dated: August 21, 1995.

Jill Long,

Under Secretary, Rural Economic and Community Development.

[FR Doc. 95-21298 Filed 8-28-95; 8:45 am]

BILLING CODE 3410-15-P