Patent GB-230866-A (GB)
Title: Improvements relating to electrical signalling and controlling systems
IPC: H02J13/00
Filed: 1925-03-17
Abstract: 230,866. Metropolitan-Vickers Electrical Co., Ltd., (Assignees of White, T. U.). March 17, 1924, [Convention date]. Selective distant control systems; tell-tale apparatus.-Relates to selective distant control and supervisory signalling systems for power stations of the type wherein chains of relays at the control station and substation are operated synchronously in sequence upon the operation of a key at the control station corresponding to an apparatus unit at the substation or the automatic change of condition of an appartus unit. The invention is characterized by the provision of (1) two line relays at each station which are energized alternately over single line to operate the relay chains, (2) a switching relay corresponding to each relay in the chains for connecting the beys and supervisory lamps at the control station to the corresponding apparatus units at the substation and (3) two sources of alternating current at each station for controlling the apparatus units and the supervisory lamps. A relay at each station is normally energized over one line wire and is de-energized to initiate the operation of the relay chains upon the operation of a key or an apparatus unit, and means are provided for releasing and restarting the trelay equipment at any point during its - cycle when a fault occurs in the system. Figs. 1 to 4 show the control station apparatus and Figs. 5 to 8 show the equipment at the substation. Each circuit breaker unit C, Fig. 6, (only one being shown) is operated by a key such as k<1> which causes pairs of relays 404, 905 and 405, 904 at the control station and substation to be alternately energized in series over a line 381 by currents of opposite polarity to operate counting relays 30 - - 21, 501 - - 510 successively and in synchronism. The counting relays operate corresponding switching relays 89 - - 80, 512 - - 521, associated respectively at the control station with control keys and' at the substation with circuit breakers. When it is desired to control an apparatus unit, the corresponding key is operated in one or other direction,- depending upon whether it is desired to open or close the circuit breaker, to prepare a control circuit and operate the relay chains in sequence until the corresponding switching relays at the control office and substation are energized. An - alternating current is then transmitted from one or other of the generators G, G<1> over a line 280 to operate a tuned relay 703 or 704 and close the circuit. of a relay for operating the circuit breaker. Supervisory lamps, such as 232, 233 provided for each circuit breaker are operated by tuned relays 213, 214 which are responsive to frequencies of the generators G<2>, G<3> at the substation. Upon the operation of each relay in the chains a signalling circuit is closed over the line 282 and the condition of each unit is checked at the control office. During the signalling operation the line 381 is opened and the operation of the relay chains is suspended for an interval of time determined by a slow-acting relay. In this manner the synchronous operation of the relav chains is ensured. When the relays corresponding to the operated key are reached, a signalling circuit is completed simultaneously with the control circuit over the contacts of the relays and a check on the original condition of the unit is transmitted to the control office. After the complete operation of the relay chains, they are again energized in sequence to signal back to the control office the changed condition of the circuit breaker in addition to a check for the positions of the remaining units. The relay chains may also be operated through a complete cycle to signal the changed condition of a circuit breaker when it is operated automatically at the substation. If the relay chains do not operate at the proper speed, slow-acting relays 416, 417, 911, 912 are operated to release the relay equipment at any point in its cycle and restart the operation. Further, if faults are present on the lines 280, 282, buzzers 221, 717 and lamps 234, 724 are operated to give an alarm. Normal conditions of system. Normallv the relays 316, Fig. 3, and 811, Fig., 7, are energized over the line 381. The relay 316 operates the relays 412, 413, 414 to prepare the circuit of a " start " relay 300. Similarly the relay 811 at the substation prepares the circuit of a " start " relay 809. Operation of circuit breaker C, Fig. 6. In order to close the circuit breaker, the key K<1>, associated with it, is operated so as to complete a ciircuit at the contacts 208, 209 and thereby prepare a control circuit at the armature 243 of a relay 211 from the alternator G<1>, illuminate a monitoring lamp 231 and complete the circuit of the " start " relay 300 over a lead 297. The relay 300 opens the circuit of the normally energized relays 316, 811 at the armature 320. When the relay 316 de-energizes, a relay 315 is operated to disconnect the line 381 from the relay 316 and connect it to a line relay 405. Simultaneously, a relay 319 operates a buzzer 318 which informs the dispatcher that the apparatus is about to function. At the substation, the de-energization of the. relay 811 connects the line 381 to the line relay 904. The relays 405, 904 are thus energized in series over the line 381. The relay 405 operates a relay 308, which in turn, operates a relay 305 and thereby energizes the first counting relay 30 over the leads 289, 162. The relay 30 prepares the circuit of the next counting relay 29 and operates the switching relay 89. Similarly at the substation, the relay 904 causes the operation of the first counting relay 501 and the corresponding switching relay 512. When the switching relays 89, 512 are operated, the " open " position of the circuit breaker C is signalled over a circuit including an alternating generator G<2>, armature 569 of the switching relay 512, alternating current relay 712, line 282, tuned relay 214 which is responsive to the frequency of the generator G<2>. The relay 712 operates a relay 800 at the armature 750 and opens the relay driving circuit over the line 381 during the signalling operation. The tuned relay 214 closes a circuit over the slow-acting relay 215, armature 150 of switching relay 89, line 171 to resistance 235. This circuit is without effect and the " open signalling lamp remains lit. The switching relays 89, 512 simultaneously completes an operation circuit which extends from an alternating current generator G', over lead 172, armature 151, lead 173, alternating current relay 226, line 280 to a tuned relay 704 which is responsive to currents from the generator G<1>. The relay 704 operates, through the contacts of the switching relay 512, the relay 705 which energizes the " closing " coil of the circuit breaker in series with a relay 718. The relav 704 also operates a slow acting relay 700 which opens the control circuit after a predetermined time interval. The slow-acting relay 216 opens the supervising signalling circuit over the line 282 and consequently de-energizes the relay 712 and completes the driving circuit over the line 381 after a predetermined time interval to prepare for the operation of the next relays in the chains. Completion of cycle of operations. The counting relay 30 is looked energized over a circuit including a relay 310 which energizes a relay 314 to open the circuit of the line relays 405, 904. The relay 314 also operates a relay 313, and consequently a relay 403 to transfer the line 381 from the relay 405 to the line relay 404. A relay 302 is also, operated by the relay 314 to energize a relay 317 and thereby de-energize the relay 314 and complete the line circuit at the armature 356. Similarly the counting relay 501 at the substation transfers the control circuit from the relay 904 to the relay 905 and prepares the circuit over the line relays 404, 905. This circuit is completed when the relay 800 is de-energized by the extraction of the armature 750 of the relay 712 as previously described. When the time relays 404, 905 are energized, the relays 307, 801 respectively are operated. The relay 307 operates to (1) open the circuit of the switching relay 89, (2) prepare the circuit of the next switching relay 88, (3) operate the next counting relay 29, and (4) operate a relay 418. The counting relay 29 operates the switching relay 88 to prepare the control and signalling circuits associated with the next circuit breaker and opens the circuit of the relay 30. The relay 29 is locked energized over a circuit including a relay 311 which is energized to open the circuit of the line relays 404, 905 and transfer the line back to the relay 405. Similarly, at the substation, the relay 801 opens the circuit of the switching relay 512 and energizes the counting relay 502. The counting relay 502 operates the switching relay 513 and opens the circuit of the counting relay 501. The relay 816 is also energized to open the line circuit and transfer the line back to the relay 904. If the key, such as K<1>, Fig. 2, associated with the next circuit breaker has previously been operated, the control and signalling circuits are closed by the switching relays 88, 513 and the circuit breaker and signal lamps are operated in a manner similar to that previously described. The relays 405, 904 are again operated to cause the operation of the next counting and switching relays. Thus the pairs of relays 404, 905 and 405, 904 are energized alternately to control the counting and switching relays. When, finally, the last relays 20, 511 in the chains are operated a circuit is established' over the relays 316, 811 and the equipment assumes its normal condition. If a second key is operated after the cycle of operations is started, a circuit is completed for restarting the relay chains at the conclusion of the previous cycle so that the control associated with the operated key may be effected. When th