Patent GB-307384-A (GB)
Title: Improvements in or relating to electrical remote control systems
IPC: H02J13/00
Filed: 1927-12-06
Abstract: 307,384. Reyrolle & Co., Ltd., A., Leeson, B. H., and King, O. C. F. Dec. 6, 1927. Selective distant centrol systems.-Relates to a remote control and indicating system in which an electromagnetic, switching device at the substation normally allows the substation indication transmitting apparatus access to certain line wires but on the actuation of the control station transmitter disconnects the substation transmitter and connects the substation receiver to the line wires. The system employs drum selectors of the type described in Specification 307,379. The lower half of Fig. 1 shows the control station connected by line wires 40 - - 42 to the substation shown in the upper half of the Figure. Selection of apparatus. The operation of selector push 230 energizes one coil 235 of the stepping magnet which rotates the control station selector 220 a half-step thus locking itself and sending an impulse over wires 41, 42 to substation polarized relay 140. Relay 140 energizes selector relay 130 which closes a holding circuit for relay 140 through coil 143 and energizes the selector relay 75 which closes the circuit of the stepping magnet 71 of the selector 70 which by closing contacts 72, 73 applies the substation battery 120 to the line wires 41, 42. At the control station when the push 230 is released the batteries 120, 210 in series energize relay 237 which is not actuated by a single battery and energizes coil 236 to step selector 220 a second half step. Selection of the third and later positions is obtained by further operations of the push 230. Indicating circuit. During selection the indicating circuit is opened at contacts 222 and on completion of the selection an indicating circuit is closed over line wires 40, 42 for the polarized relay 200 from the indicating bus bars 160, 161. In the first position " off normal " of the selector 70 the bus bars 160, 161 are connected through contacts 51, 52, 93, 94 to the substation. battery 120 with polarity depending on the position of the circuit breaker 50. The polarized relay 200 energizes one or other of relays 203, 204 controlling lamps 285, 286. In the third position the indicating bus bars 160, 161 are associated with a thermostatic switch 60 and associated relay 62. Operation of circuit breaker. Push 240 trips and push 250 correspondingly closes the selected circuit breaker by energizing line wires 41, 42 to operate relay 140 in the opposite sense to that in which it was energized during selection so that executive relay 150 is actuated and closes a retaining contact 155 and a contact 154 in the circuits of the trip relay 180 and the close relay 185. These circuits also include contacts 54, 55 associated with the circuit breaker so that the latter, if open, is closed by the energization of the appropriate operating coils 57 or 58, relay 180 or 185 being meanwhile locked by contact 183 or 187. Transmission of meter readings. The desired contacts on selector 70 are selected and executive relay 150 is operated by metering push 260 which when released leaves contact 262 operated until released by movement of the selector 220 so that metering bus bars 162, 163 are connected to line wires 40, 42 with which meter 266 is associated. The bus bars 162, 163 are connected through the selector 70 to a current transformer 61. Telephone and alarm circuits. These are associated with the zero or normal contacts of the selectors. The telephone push 270 extinguishes lamp 285 and lights lamp 284 to indicate that the system is inoperative and energizes line wires 41, 42 so that executive relay 150 is operated to complete the telephone buzzer 170 and speaking circuit 171 over the metering circuit 40, 42. Calls from the sub-station are effected by push 173 which is electromagnetically locked by electromagnet 176 in all except normal position of the selectors. Current interrupted by interrupter 177 is thus sent over line wires 40, 42 to the control station and operates relay 200 to operate relay 203 and since the alarm position relay 290 is energized in the normal position of the selector, lamp 286 is lighted and buzzer 287 is operated. An alarm is given by the automatic operation of a circuit-breaker or the operation of thermostat 60 causing the alarm relay 190 to be energized momentarily. Relay 190 locks itself until released by operation of the selector and supplies current to line wires 40, 42 in opposite direction to that of a telephone call. The operation of relay 200 thus energizes relay 203 or relay 204 depending on whether a telephone or alarm call is sent to change over lamps 285, 286 and operate the buzzer 287. Relays 203, 204 control separate indicator discs so that a distinguishing indication is given; moreover in the case of a telephone call interrupfer 177 is in circuit so that the buzzer 287 is intermittently operated. If an alarm is initiated when the selector is " off normal " the alarm relay 190 is energized and locked, but the alarm is stored until the selectors are returned to normal. Modification of alarm circuit. To enable an alarm to be given to the control station during the time meter readings are being taken the substation alarm relay 190 may be provided with extra contacts controlling an auxiliary alarm relay 330, Fig. 3, and its retaining circuit includes contacts of a time limit relay 340 energized by the auxiliary relay 330. With this arrangement an alarm during metering breaks the circuit over line wires 40, 42 and establishes the alarm circuit over line wires 41, 42. A metering relay 156 controlled by relay 150 is provided so that the auxiliary relay 330 is energized only in metering selector positions. The alarm energizes relay 360 which locks itself and the alarm circuit is maintained until the timelimit relay 340 operates and the metering circuit 41, 42 is re-established. Arrangements for express selection. To obtain express selection after the operation of contacts 232, 233, Fig. 1, if both sets of contacts are closed the re-setting movement of solenoid 236 will automatically re-energize the starting solenoid 235. These connections may be effected by a special push or by the provision of extra contacts on the push 230 which are closed by rotating the push or alternatively by retaining the push depressed. A barometer type pointer carrying contacts and co-operating with the selector pointer may control a relay so that the express selection is stopped when the pointers are in agreement. Automatic operation of selectors on receipt of an alarm. When self-recording indicating mechanism is employed at the control station it is necessary to arrange that the receipt of an alarm signal causes the selectors to perform a complete selecting and indicating cycle. In this modification (Fig. 2 not shown) the control station alarm position relay 290 is energized in the normal position of the selectors so that an alarm causes relay 204 associated with the polarized relay 200 to energize an additional alarm relay which locks itself and starts an express selection and energizes an auxiliary relay which gives the alarm and locks itself till released by the station attendant. The operation of the selector to the fourth position releases the additional alarm relay but the selecting circuit is maintained by contacts of the auxiliary relay in conjunction with contacts operated by cam on the selector shaft so that the selecting and indicating cycle is completed. The control operator can check the system by energizing the additional alarm relay. Modified system employing pre-selector relays. This system is fully described with reference to Fig. 28 of Specification 307,379. The selecting and executive pushes (Fig. 4 not shown) respectively are associated with transmitting coils and a release coil of a transmitting switch the. construction of which forms the subject-matter of Specification 307,385 and provides for the locking of the control station apparatus during selection. The control station selector is driven a half step by the selecting impulse and an additional half step by the energization of the release coil from the substation. Indications are given from the substation by means of a similar switch and actuate an indicator also described in Specification 307,385 having positive and negative coils respectively corresponding to coils 460, 465, Fig. 28, of Specification 307,379. The centralization of the armature of the indicating switch (Fig. 7 not shown) leaves a, slide in its last operated position until centralized by the control station selector, so that an alarm causes an express selecting and indicating cycle to be started which is stopped by the absence of indicating current in the " normal " position since the operation of the substation selector will have de-energized the alarm relay at that station. A checking, selecting and indicating cycle can be started by the control station operator moving the slide to the alarm position by hand. Construction of pre-selector relay. Fig. 8 shows a modified construction of pre-selector relay comprising a beam restored to normal by gravity and carrying insulated members 436, 437, 438 connected to the line wires 426 - - 428 and co-operating with contacts 440 - - 449 corresponding with similarly numbered contacts in Fig. 28 of Specification 307,379. The operating coils 432, 433 are unequally spaced from the pivot so that precedence is given to one function in the event of simultaneous operation without interfering with the normal operation from either the control or substation. This type of switch may be extended for more complicated systems such as by duplication of the transmitting and receiving apparatus. In this event the beam is replaced by a plate mounted on a central ball joint operated by more than two magnets the desired exclusive use of the line wires for the function first started being obtained by mechanical interlock. Specifications 307,381 and 307,3