Patent GB-298470-A (GB)
Title: Improvements in or relating to electric remote control systems
IPC: H02J13/00
Filed: 1928-09-19
Abstract: 298,470. Associated Telephone &. Telegraph Co., (Assignees of Belliveau, A. H.). Oct. 8, 1927, [Convention date]. Selective distant control systems; tell-tale apparatus.-In a system for controlling and supervising the operation of apparatus at a number of substations over common conductors the operation is effected after selection by the closing of a chain circuit when the stepping switches at all the stations are at normal. Fig. 1 shows the apparatus at the despatcher's station comprising selecting and operating key sets k<1>1, K1, with indicating lamp sets 43 - - 45, a sender switch SEN and a supervisory switch SUPY. Figs. 2 and 4 show the apparatus at substation SN1, and in outline that at substation SN2 and Fig. 3 shows the apparatus at the terminal substation SN3. Selection, of apparatus. Actuation of Key K<1>1 selects the apparatus associated with the first contacts of the stepping switches by impulsing relay 3 through self-driving relay 6 which interrupts contacts 55. Slow release relays 2, 1 are energized so that the line 80 and relays 4, 101. 110 and 301 are impulsed to drive stepping magnets 5, 102 while slow release relay 8 maintains the control line 81 open. When wiper 24 reaches the marked isolated contact stepping ceases and all relays de-energize. Operation of apparatus. Actuation of key K1 actuates polar relay 104 in direction depending on the key actuation to operate trigger relay 107 or 108 to operate the high potential relay connected to contacts 128 or 130 which control the switching device when contacts 131 are closed. The restoration of Key K<1>1 restores neutral to the marked contact and isolates the normal contact so that stepping at all stations proceeds to normal, when if wipers 26, 138, 139, 342 are in step a chain circuit is closed over the control line 82 by relay 11 for relays 109, 111, 302 so that the operation is effected by closing contact 131. Thus the operation is ineffective if the stepping -switches are not in agreement. Correction of displacements between stepping switches.-Key contacts 71, 72, apply alternating current to lines 80, 81 to actuate relays 113, 115, 314. Considering substation S.N.1 relays 114, 104<1> are energized so that stepping magnet 102 is energized and being self interrupting over this circuit steps itself to normal at which point the slow to attract relay 114 has isolated the normal contact for wiper 137. Relay 114 in addition opens at 150 the circuit by which trigger relays 107, 108 are locked energized thus neutralizing any operation that has been attempted. Tell-tale apparatus. The movement of the controlled apparatus either automatically or under control changes contact 257, Fig. 4, causing signal relay 218 to de-energize and actuate relay 217 which energizes relays 212, 213, 214. Relay 213 locks and opens the circuit of start relay 210 and the chain circuit at contacts 255 for effecting control through relays 109, 111, 302, until it is shunted out by the slow to attract relay 214. In addition relay 217 removes neutral from the first contact of wiper 249 and closes the circuit of the start relay 210 which energizes relays 209, 203 and 204. Impulse springs 232 of the interrupter relay 202 cause relay 203 to be impulsed so that relay 208 is energized and closes the impulsing circuit to line 81 at 240 thus impulsing relays 200, 18 which control stepping magnets 216, 12. The cessation of the impulses on reaching the marked contact of the counting switch OS causes relay 17 to de-energize and actuates relay 21 to change over contacts 67 which in conjunction with the key k1 control the lamp indicators 43 - - 45. At the substation SN1 the de-energizing of relay 208 on the cessation of the impulses to relay 203 actuates the chain of relays 207, 206, 205 and the latter at contacts 272 energizes relay 218 over wiper 250 and releases relay 217. Wiper 249 is thereby connected to neutral to re-operate relay 203 so that the counting switches CS and the supervisory switch SUPY are stepped to normal. Preventing interference between substations. The de-energization of signal relay 218 causes actuation of companion relay 217 which places neutral on conductor 283 to complete a circuit through the contacts of the normally energized relay 211 for the start relay 210. At the substation SN3 when neutral is_placed on conductor 283<1> by a signal relay a delay relay chain 303 - - 305 precedes the start relay 306 so that in the event of simultaneous operation the start relay at SN1 would energize first and moving the counting switches off normal de-energizes relay 307 which opens the circuit of relay 303 until the counting switches return to normal when the relay 307 would be energized and the signal transmitted. Correspondingly the actuation of a signal relay with the counting switches OS off normal is ineffective until these switches return to normal as relays 211, 307 are de-energized.