Patent GB-413682-A (GB)
Title: Improvements in routine testing arrangements particularly for automatic telephone exchange systems
IPC: H04Q1/24
Filed: 1933-01-18
Abstract: 413,682. Automatic exchange systems. SIEMENS BROS. & CO., Ltd., Caxton House, Tothill Street, CHRISTIAN, D. A., Morven, Charlton Road, and DIBBEN, W. H. J., 44, Wellington Road, Charlton, both in London. Jan. 18, 1933, No. 1661. [Class 40 (iv).] A routiner comprises a number of test elements which are applied in succession to the apparatus under test by a test'selecting element, each test element being independent in the sense that it can be removed and replaced by a different element without interfering with the wiring or working of the other test elements. The test selecting element is controlled by a discriminator which arranges for the application of only the test elements appropriate to the particular apparatus being tested. The routiner described is for testing final selectors some of which serve two hundred lines and some of which serve large and some small P.B.X. groups. The figures of the drawing can be assembled as shown in Fig. 20 to form a complete diagram. The manner in which the leads are connected is indicated by code numbers e.g. 6.0114 means the sixth lead running between Figs. 1 and 14. General operation. The system described comprises primary, secondary and access distributers PD, SD, AS, Figs. 3-8, each of which comprises two switches which are stepped together, test selecting and discriminating switches T, D, Fig. 15, each of which comprises a pair of switches the second of which is made operative when the first reaches the end of its bank and which arrange for the application in succession of tests appropriate to the particular switch under test, a number of separate and easily replaceable test elements, Figs. 16, 17, connected to successive terminals of the switch T and a counting and sending set Figs. 16, 19 which is associated with certain test elements for sending impulses to the switch under test, measuring release time &c. On the successful completion of each test the switch T is stepped on to initiate a new one, the completion of the cycle causing the access distributer to select the next switch for test. If any of the apparatus fails to pass a test or if the routiner itself fails to operate correctly the failure of the switch T to receive a stepping impulse causes an alarm to be given. Keys are provided to enable a particular switch to be selected and put through the test cycle repeatedly, to enable the test cycle to be repeated on a faulty switch after the fault has been cleared, to step the access distributer away from a faulty switch without clearing the fault and for simulating certain faults to test the operation of the routiner. Lamps are provided for indicating the nature of faults in the routiner itself and in the switches under test. Distributing arrangements. A test of all the final selectors in turn is initiated by the operation of key STK, Fig. 12. SR, Fig. 2, pulls up energizing RV, PS, HD which are followed by the magnets PDDM, PDADM, Fig. 4, of the primary distributer and by relays SH, TF, ST, S, SV, Fig. 2, and DS, AS, Fig. 1. S releases RV, PS whereupon the magnets fall back moving the distributer to its first terminals. If these terminals are unequipped the PD1, PDA1 terminals are connected at the frame pdt, rut to RU which pulls up in series with the magnets, holds SH and shunts its high resistance winding to allow the magnets to energize. The magnets then step by selfinterruption until the wipers PDAI, PD1 find the terminals of an equipped line which are connected to pst1 and are therefore dead. RU, SH then fall releasing DS. Before DS has time to fall however a momentary circuit is made over PDA7 for relay DA in the selected secondary distributer. DA energizes the secondary distributer magnets SDDM, SDADM and then falls allowing the distributer to step on to its first terminals. If these are unequipped the switches advance by self interruption in series with SU until an equipped position is found, SU holding TF after the relapse of DS. When an equipped position is reached, TF and AS fall in succession so that an impulse is sent to ASR, Fig. 8, which starts the access switch. If the first terminals are unequipped the switch hunts by self interruption in series with PU which holds ST after the relapse of AS. When an equipped position is reached the switch stops and PU, ST fall and the test cycle is initiated. At the conclusion of the test TF is operated from the discriminator and is followed by AS, ST, SV, and TS falls back to send the dis. criminator home. When the latter moves on, TF, AS, ST fall in suc. cession so that an impulse is sent via PD8, SD8 to ASR to give an impulse to the access switch magnets and the test cycle is then repeated on a fresh selector. When the access switch moves off the last equipped terminal it goes home by self interruption in series with AF, Fig. 2, which thus gives an impulse to DA to drive on the secondary distributer and to TF to cause the next access switch tc move on to its bank. The secondary distributer in position 24 energizes SF, Fig. 2, which locks. When now the access switch reached in this position finishes and energizes AF, SD is operated also energizing PS, SH, DS, TF, AS. On the relapse of AF, to send the secondary distributer home, SD falls followed by PS, SH, DS, TF, AS. As a result, the primary distributer is stepped on and also a new secondary distributer and access switch. When the primary distributer leaves its last equipped position (20) it energizes RF which gives audible and visible signals, and energizes ST. Restoration of key STK releases SR, HD to home the primary distributer and the last secondary distributer. For continuous testing of a particular selector, key CTK is thrown to energize CR and connect up keys SK for stepping the distributer and access switches to the appropriate positions. When it is necessary to step the access switch away from a faulty selector, SOK is operated temporarily to give an impulse to TF which steps on the access switch. To repeat the test cycle on a faulty switch, REK is operated, energizing RE which disconnects the alarm relay AL and energizes ST which energizes SW releases TS. TS releases TU, Fig. 15, which homes the discriminating switches described below and releases TV to home the test selecting switches. When the key is released, RE, ST, SV fall in succession and TS, TU, TV pull up to re-start the test cycle on the same selector. Discriminating and test selecting switches. One set of terminals (e.g. those numbered 99) in each final selector (or one set in each bank in double wiper selectors) is allotted for test purposes. When a final selector is engaged by an access switch and provided the line reached over the test terminals is idle its relay OA Fig. 9 switches the test terminals from the associated subscriber's line to the leads oal 2-oal 4, Figs. 9, 5, 3, 1, 14. In the case of a double wiper selector OA also, provided the line reached from the alternative test terminals is idle, energizes OB, Fig. 10, which switches the alternative test terminals to the leads obl 1-obl 4 and energizes OBX, Fig. 2. Each final selector has a terminal oat 6, Fig. 9, which is jumpered to oet in ordinary selectors and to oft in 100-line selectors serving multi-level P.B.X groups. In those serving single-level groups the terminal is left unconnected but relays OC, OD, Fig. 11, are provided and are controlled by OA in 100-line selectors and by OB as shown in 200-line selectors. These relays, provided the corresponding lines are idle, appropriate terminals 98, 90 for test purposes and OA in such cases marks 97 as the last line of the P.B.X. group in which the test lines occur. As a result of these connections and of a circuit over ASW 8 one of the relays OF, OE, OCX, with or without TD, Fig. 15, is operated to select one of the pairs of wipers DA and DB 3-8 according to the type of switch under test on the operation of OA. These relays energize TL, Fig. 2, whereupon SV falls and TS pulls up energizing TU, Fig. 15, which energizes TV. TU, TV energize the driving magnets of the distributer and test selecting switches which move by self-interruption to their first terminals. TV also energizes TE, Fig. 17, to prepare certain test elements for operation. IC which is energized over TA2 and TB2, DA2 and DB2 grounds the selected wiper DA and DB 3-8. If the first test is appropriate, this wiper will be on a terminal connected to cwl and the ground is accordingly extended to the first wire tcl extending from bank TA4 and TB4 to start the first test. If the selector responds successfully the test element grounds tcle to energize TC which energizes CD and the stepping magnet of the test switch CD removes the initiating ground from cwl whereupon the test element removes ground from tcle, TC falls and the wipers of the test switch are moved releasing 1C which unlocks CD and energizes the magnet of the discriminator. On the relapse of CD, this circuit is opened and the discriminator wipers move on re-operating IC which again grounds the selected wiper DA and DB3-8. In positions corresponding to inappropriate tests this wiper engages a terminal connected to zdl and when IC pulls up, ZD pulls up and grounds tcle to cause the discriminator test switches to move to the next position. In the case of certain tests which have to follow one another with a minimum loss of time, the test element grounds tstl instead of tcle to step the test selecting switch directly, the discriminator remaining stationary. For subsequent tests the test and discriminator switches remain out of step. At the completion of the test cycle, the wiper DA and DB3-8 encounters a terminal jumpered to tcf, and when IC pulls up, ground on this wire energizes TF, Fig. 2, to signal the completion of the test. The resulting relapse of TS releases TU, TV, Fig. 15, to home the discriminator and test switches and release TE, Fig. 17. General arrangement of test elements. The lines marked t + l, t-l, tpl, tcl in