1、 T/CS54-07E Page 1 - Recornmendation TICS 54-07 (Vienna 1982) ANALOGUE SUBSCRIBER LINE TESTS AND MEASUREMENTS Recommendation proposed by Working Group T/No. 11 “Switching and Signalling” (CS) Text of the Recommeridation adopted by the “Telecommunicatiois” Cormiission : “The European Conference of Po
2、stal and Telecommunications Administrations, considesing - that analogue subscriber lines are currently generally used and will continue to be used to a great extent in the - that on the basis of the dened maintenance philosophy, procedures for testing, measuring and monitoring, - that existing prac
3、tice for analogue subscriber iine maintenance shows a considerable variance in solutions; - that system independent equipment, as well as the integration of some or all of these functions into digital local foreseeable future; together with the field of application for subscriber line maintenance, a
4、ll need to be specified; exchanges may be used, O secommends that the members of the CEPT use for new exchanges, and/or system independent test and/or measurement equipment, the procedures for analogue subscriber line tests and measurements set-out below.” GENERAL INTRODUCTION - FELD OF APPLICATION
5、This Recommendation covers the maintenance of an analogue subscriber connection. Referring to the Figure 1 (TICS 54-07), three parts can be recognized in this connection: - the subscriber set or STE (subscriber terminal equipment); - the transmission part of the subscriber connection; - the exchange
6、 terminal (ET). The ET can be situated in a local digital exchange or in a remote multiplexer or concentrator. Special categories of lines (e.g. party lines, analogue subscriber carrier systems, concentrators, service restrictions indicated by the presence of ground on one of the wires, etc.) are no
7、t covered in the present Recommendation. The test and/or measurement procedures to be used in such lines is for further study. anaiogue te lep hon y PART 1: OUTWARD TESTS AND MEASUREMENTS This part of the Recommendation considers only the outward tests and measurements of the subscriber set and the
8、subscriber line. Edition of May 15, 1986 CEPT T/CS*54-07*E 82 232b414 0005180 8 TICS 54-07 E Page 2 1. 1.1. 1.2. 1.3. 1.4. 1.5. 2. 3. 3.1. 3.2. GENERAL REQUIREMENTS In order to adequately perform the tests of the subscriber set and subscriber line, the exchange must be capable of preventing disturbi
9、ng influences from the exchange terminal to the line, e.g. by complete disconnection. It must be possible to connect any subscriber line via an appropriate access to the test equipment, e.g. a metallic path. It should be possible to initiate the tests and/or measurements and to receive the results l
10、ocally or at a remote work position, For some tests and/or measurements, initiation will take place from the subscribers premises. With respect to the line tests and/or measurements, each subscribers line will be in one of the following states : - fault free line; - line not tested; - faulty line. A
11、 faulty line may be blocked or marked. The term blocked means that the line is blocked to calls due to a detected fault. The term marked means that the line has been indicated as faulty because of failure but is not blocked to calls. Only free lines will be able to be tested and/or measured by all t
12、he methods described in this Recommenda- tion. When the line is not tested, the reason why it is not tested will be presented, except if the line is not installed. When the subscriber line is tested or measured without the knowledge of the actual subscriber, the subscriber should be kept as unaware
13、of these actions as possible (e.g. bell-ringing, clicks, etc.). TEST AND/OR MEASUREMENT METHODS Three test and/or measurement methods can be distinguished : A. tests initiated from subscribers premises (on demand, by dialling a special code); B. tests and/or measurements initiated from administratio
14、ns premises (on demand, usually via a man- C. automatic tests (automatic routine tests and/or measurements, automatic tests on a call-by-call basis). The choice of the applied procedure(s) (e.g. omitting the automatic tests on a call-by-call basis) depends on technical and economical considerations
15、that can be different for each Administration according to the structure of the network and the organization of maintenance. It should be in accordance with a general maintenance philosophy. machine interface, e.g. control desk); TESTS INITIATED FROM THE SUBSCRIBERS PREMISES These tests provide main
16、tenance staff with the ability to access a ringback service from the subscribers premises, in order to initiate some tests on the line and the terminal equipment. These tests should also be possible from any point in the local network, by means of a portable telephone set. The following call procedu
17、re could be adopted (needs further study) : - maintenance staff member dials a particular access code on the set to be tested; - the exchange sends back a tone indicating whether the test equipment is available or not; - the successive actions to off-hook and on-hook enable the different tests to be
18、 made. Note: The different test to be made could also be selected by differing access codes, determining individual test or groups of tests. From the subscribers premises, the following tests are implicit in the call procedure: 1. dial performance; 2. multifrequency keying performance; 3. test of be
19、ll functions. Edition of May 15, 1986 TICS 54-07 E Page 3 3.3. The following tests can also be provided optionally: 1. foreign DC and AC voltages; 2. insulation resistance; 3. power supply, current or loop resistance; 4. meter at subscriber?s premises; 5. loop capacitance; 6. quality of speech trans
20、mission (telephonometry); 7. extensive MFPB or dial performance tests. 4. TESTS AND/OR MEASUREMENTS FROM ADMINISTRATION?S PREMISES These detailed tests and/or measurements are initiated from local or remote man-machine terminals. They can be initiated after the examination of the fault reports resul
21、ting from previous automatic routine tests, previous automatic call-by-call tests or on the basis of subscriber complaints. They have priority over automatic routine tests. Lines with a permanent busy condition should be able to be tested and/or measured from Administration?s premises. Where subscri
22、ber co-operation exists, a speech connection is assumed. When tests are being done without subscriber co-operation and the subscriber is making a call attempt, the tests or measurements should be aborted. They should also be aborted, if possible, when an incoming call is made to the subscriber line
23、being tested. In the following, tests and/or measurements from the Administration?s premises are identified. The actual tests to be performed, fault limits, the lines to be tested and the test moment) may be controlled by man-machine-communication. 4.1. Without co-operation at subscriber?s premises:
24、 1. foreign DC voltage : - between a and b - a to ground - b to ground; 2. foreign AC voltage: - between a and b - a to ground - b to ground; 3. insulation resistance: - between a and b - a to ground or to exchange battery - b to ground or to exchange battery; the last two tests of point 3. above ma
25、y be replaced by a to ground or to exchange battery, with b connected to a; 4. loop continuity: measurement of the capacitance a to b; 5. data for the localization of line faults; 6. test of the test access and the connection between the line and the ET. 4.2. With co-operation at the subscriber?s pr
26、emises: 1. dial performance: - number of pulses received - dial speed - pulse ratio; - digits received (A, B, C, D included): go/no-go test only; in the case of a no-go result, the frequency, level and pulse length measurements can be optionally provided ; 2. MFPB performance: 3. test of the meter a
27、t subscriber?s premises; 4. payphone signals need further study; 5. call test, a functional test of the subscriber set: ringing, talking, listening; 6. test of the register-recall signal; 7. test of special conditions on the line, e.g. subscriber controlled service restrictions; 8, measurement of th
28、e loop resistance and/or feeding current. It should be possible to define a basic subset of the tests under Section 4.1. which could be initiated by a O single command. Edition of May 15, 1986 CEPT T/CS*54-07*E 2 2326434 0005182 L TICS 54-07 E Page 4 For each on-demand test, the exact values of the
29、measurements of the specified parameters should be presented, as well as the fault limits and a passfail indication. Before an on-demand test is made, a check to determine the presence of a call on the line should be performed. 5. AUTOMATIC ROUTLNE TESTS AND MEASUREMENTS Automatic routine tests are
30、performed on some OS all subscribes lines at predetermined times, usually at night, e.g. once a week. Some specific automatic routine measurements which give more detailed and statistical information about the subscriber lines and associated local cable network may also be done. In this case, the me
31、asured value of all measured lines is presented and the frequency of these measurements may be lower. When the automatic routine test is applied on a call-by-call basis, it can be used for lines not previously tested and on lines found faulty during the call-by-call tests. Faulty lines should be tes
32、ted periodically with an interval that can be changed by commands. A line which is found correct should no longer be stated faulty. The testing equipment should be able to recognize the state of the lines in use (see Section 1.4.). Spare (unused) lines need not be tested. During a test cycle coverin
33、g all the lines, free lines are tested and busy lines are identified. After this test cycle, the lines previously identified as busy may be tested in a second test cycle. Each line can then be classified as correct, faulty or busy. At the end of the automatic routine test, a list is presented giving
34、 the directory and/or equipment number of the lines that are faulty or busy, and of the lines no longer stated faulty. The test limits and periods will also be indicated. When a subscribes initiates a call during a measurement testing on his line, the test or measurement should be aborted as soon as
35、 possible and in a way that causes minimum effect on the service offered to the subscribes, e.g. delay to dial tone, clicks on line, etc. When an incoming call is made to a subscribes line which is being tested or measured, the test or measurement should, if possible, be aborted too. The results of
36、the automatic routine test are of the type golno-go. However, the equipment should, in the case of automatic routine measurements, also be able to present the real measured value of the specified parameters. Further processing of such type of data, e.g. for more detailed or statistical information,
37、need not necessarily be done by the line testing and/or measuring equipment itself. A faulty line should only be blocked in case of excessive AC or DC voltage detected on the line. The line testing equipment should automatically check itself, either periodically, or after a predetermined number of c
38、onsecutive tests with results out-of-limit. Man-machine-communication facilities which may be local OS remote must be provided in order to specify: - the lines to be tested and/or measured; - the start time and the frequency of tests and/or measurements; - the subset of tests and/or measurements to
39、be performed; - the fault limits; - the destination and presentation of the output. The following automatic routine tests and/or measurements are identified; however, the actual tests to be performed, fault limits, the lines to be tested and the test start time and frequency may be controlled by man
40、-machine-communication. 1. foreign AC voltage : - between a and b - a to ground - b to ground; 2. foreign DC voltage: - between a and b - a to ground - b to ground; 3. insulation resistance: - between a and b - a to ground or to exchange battery - b to ground or to exchange battery; the last two tes
41、ts may be replaced by a to ground or to exchange battery, with b connected to a; - measurement of the capacitance a to b. 4. loop continuity: The initial voltage tests should be compulsory, no further tests should be applied to lines failing the voltage tests. All measurements to ground refer to exc
42、hange ground. Edition of May 15, 1986 TICS 54-07 E Page 5 6. AUTOMATIC TEST ON A CALL-BY-CALL BASIS At every call Set-up, a subscriber line test is performed, both on the calling (A-) and the called (B-) subscriber line. The test is performed after the seizure for the A-subscriber, before the dial t
43、one for the B-subscriber, and before the ringing current is sent, or after clear-down for either A- or B-subscriber. The Cali-by-call test must be such that the network service performance and network technical performance parameters are met, e.g. dial tone delay. Lines which are found faulty should
44、 be either marked or blocked, depending upon the severity of the fault (see Section 1.4.). The following tests, on a call-by-call basis, should be provided. However, the tests to be performed, fault marking limits and fault blocking limits may be controlled by man-machine-communication. 6.1. Foreign
45、 voltage 1. foreign DC voltage: - between a and b - a to ground - b to ground; 2. foreign AC voltage: - between a and b - a to ground - b to ground. 6.2. Insulation resistance 1. A-subscriber: 2. B-subscriber : - a to ground, with b wire connected via the telephone set; - a to ground, b to ground (t
46、his may be replaced by: - between a and b. a to ground, with b connected to a); All measurements to ground refer to exchange ground. 7. PARAMETER VALUES In Tables 1 (T/CS 54-07) and 2 (T/CS 54-07), an overview of all tests and measurements is given. The ranges and accuracies for measurements are min
47、imum requirements. When the value of the parameter is outside the provided range, an indication should be given. This indication should be an out-of-range indicator and/or the maximum or minimum value of this range. Note: The ranges mentioned, as compared to accuracy, are to specify the accuracy onl
48、y and are not intended to specify the measuring sub-ranges of the actual equipment. Edition of May 15, 1986 CEPT T/CS*54-07*E 2 = 2326414 0005L4 5 W TICC 54-07 E Page 6 e Test and/or mea- surement methods Measuring range R and accuracy A Applicable test procedures State of STE Function la: to detect
49、 and measure foreign AC voltage Foreign AC voltage: - between a and b - a to ground - b to ground R: 0-300 V r.m.s. A: 2 ranges a) 0-20 V: I2V b) 20-300 V: - automatic routine tests. 3. ON-DEMAND TESTS AND/OR MEASUREMENTS These tests and/or measurements are initiated from local or remote measurement man-machine terminals. They can be initiated after the examination of fault reports resulting from the automatic routine tests or on the basis of subscriber complaints. They have priority over automatic routine tests. Edition of May 15, 1986 CEPT T/CS*54-07*E 82 W 2326434 0005386 -
