Patent GB-267130-A (GB)
Title: Improvements in or relating to electrical signalling and/or controlling systems
IPC: H02J13/00
Filed: 1927-03-02
Abstract: 267,130. Metropolitan-Vickers Electrical Co., Ltd., (Assignees of White, T. U.). March 2, 1926, [Convention date]. Selective distant-control systems; tell-tale apapparatus.-Relates to an electric supervisory control system for apparatus units, such as circuit breakers, at a substation, wherein chains of relays at the control office and substation are driven in synchronism to effect a selection at the substation corresponding to the operation of a key or operate a supervisory signal upon the change of condition of an associated apparatus unit. The apparatus units and supervisory signals are associated with groups of relays and any particular selection is effected by firstly selecting a group of relays, and, secondly, operating a particular relay in the selected group. When an apparatus unit is selected, a checking signal is sent back from the substation prior to the operation. If the checking signal indicates that an incorrect selection has been made the operation of the relay chains may be stopped to prevent actuation of the selected unit. Figs. 1, 2 and 3 show the control station apparatus and Figs. 4 - - 7 show the equipment at the substation. Circuit breakers 600, 601 are provided with individual control keys 102, 105 at the control station associated with a common master control key 107 which according to its position determines the nature of the operation e.g. " open " or " close " to be effected. The keys and circuit breakers are arranged in groups, selection of any particular circuit breaker being accomplished by effecting a group selection by operation of one or other of the group selecting relays 706, 709, Fig. 7, and then operating a final selecting relay in a group such as 714 - - 723. Relay chains 200 - - 212, 401 - - 413 at each station are operated synchronously under the control of chains of relays 213 - - 268, 414 - - 441 driven by pairs of relays 309, 314 and 511, 515 which are alternately energized in series over the line arm d by impulses of opposite polarity. The operation of the synchronously driven relay chains is initiated by a "start" key 108. Group selection of a circuit breaker is effected by the relays 200, 401 and final selection by corresponding relays in the groups 201 - - 205, 402 - - 406 which are marked by the operated control key. The relays 206 - - 211, 407 - - 412 in the chains are utilized for effecting the transmission of checking and supervisory signals and the relays 212, 413 complete the final control and supervisory signalling circuits. When upon continued operation of the relay chains, the relays 206, 407 are operated a group selection is effected according to the selected relay in the group 714 - - 723. Thus one or other of the relays 159, 130 is operated to associate a group of final selecting relays such as relays 132 - - 141 with the chain 207 - - 212. When corresponding relays in the groups 207 - - 211, 408 - - 412 characteristic of the final selection at the substation are operated, a relay on the group 132 - - 141 is operated to prepare the supervisory circuit and illuminate a lamp such as 161 which provides a check on the selection prior to the operation of the selected circuit breaker. Upon operation of the final relays 212, 413 the control circuit is established over the line c from one or other of the alternators 191, 192 over the contacts of the master-key 107. Resonance relays at the substation operate the circuit breaker, which upon changing its position transmits an impulse over the line s to reverse the indication of the associated supervisory lamps 103, 104. Communication with a selected circuit breaker may be maintained by the operation of a key 109 which interrupts further working of the relay equipment when the relays 212, 413 are energized. The supervisory lamps may also be operated upon the automatic operation of a circuit breaker. In this case the key 109 may be operated to maintain the relays 212, 413 energized and thereby prevent cancellation of the indication given by a lamp such as 161 so that if an automatic change takes place during the absence of the operator, immediate notice of the unit which has changed its position is given. Arrangements are made for preventing the mutilation of control or supervisory signals in the event of simultaneous operation of the keys or circuit breakers. Normal condition of system. Normally the relays 305, 501 at the control and substation respectively are energized in series over the line wire d. The relay 305 prepares the circuit of the line relay 309 and operates a relay 304 which prepares a relay 302 for operation. Selection of circuit breaker. Assuming it is desired to select the circuit breaker 601 for operation, the appropriate key viz. 105, the master key 107 and the " start " key 108 are operated. When the " start " key is operated, the relay 302 is energized to complete a series circuit for the relays 302, 303. This circuit is however inoperative until the key 108 is released to remove the short circuit across the relay 103. The relay 303 is then operated to open the normal series circuit for the relays 305, 501. De-energization of these relays causes the operation of relays 310, 509 to connect the line relays 309, 511 in series over the line d. The relay 309, 511 operate relays 307, 515 respectively. The relay 307 operates the relay 213 to complete a series circuit for the relays 213, 214, which, however, remains inoperative. The relay 511 simultaneously operates relay 414 which closes the series circuit of relays 414, 415. The relay 307 also energizes a relay 316 which operates a relay 316 to open the line circuit. The line relays 309, 511 are thus de-energized and in consequence relays 214, 415 pull up and operate the selecting relays 200, 401. The selecting relays energize relays 311, 518 respectively to prepare the line circuit of the line relays 314, 515 and cause the operation of the relays 315, 510. Selecting relay 200 also short circuits a relay 319 which causes the de-energization of relay 318 to complete, the line circuit. Line relays 314, 515 upon energization operate the next relays 255, 428 in the chains and by reason of the operation of relay 312 cause the energization of relay 318 to again open the line circuit. When the line relays 314, 515 are de-energized the next chain relays 256, 429 are energized to operate the next selecting relays 201, 402. Operation of these relays transfers the line circuit to relays 309, 511 and a further impulse is sent into the relays chains to cause operation of the next selecting relays. The remaining selecting relays at each station are operated in a similar manner. The first relays 200, 401 in the selecting groups effect a group selection i.e. they connect up a group of selecting relays at the substation corresponding to the group of control keys containing the operated key. The operated key 105 energizes an individual relay 126, which closes a circuit over the line c through appropriate contacts on the selecting relays 200, 401 and normally closed relay 705 at the substation for the corresponding group relay 109 which when energized places the final selecting relays 714 - - 723 under the control of the groups 200 - - 205, 401 - - 406. In the event of operation of the key 102 and its individual relay 128, group selection is effected through different contacts on relays 200, 401 and line wire s. During the operation of the remaining relays in these groups an impulse is sent over one or other of the line wires c, s upon operation of the relay in the group 201 - - 205 marked by the operated key to select the appropriate relay in the group 714 - - 723 at the substation. Thus since the relay 201 is associated with the operated individual relay 126 an impulse is transmitted, upon operation of the relay 201, over the line c to energize the corresponding relay 715 which prepares the circuit for the selected apparatus unit and the circuit for transmitting a checking signal of the selection prior to the operation of the unit. Checking the selection. When after continued stepping of the selecting relays, the relays 206, 407 are operated, a circuit is closed over the relay 715 and line s for a relay 152 which effects the appropriate group selection at the control station by associating the groups of relays 132 - - 141 with the relays 207 - - 212. If a different group of relays at the substation is selected, the group selection at the control office upon operation of the relays 206 407 is effected over the control wire c. When the relays in the groups 207 - - 212, 408 - - 413 corresponding to the selected unit are operated a circuit is established over one or other of the line wires c, s, and the contacts of relays 715, 152 for a relay such as 140 which operates the lamp 161 to check the accuracy of the selecting operation. If the checking signal shows that selection is effected incorrectly a key 106 may be operated to energize a relay 123<a> which unlocks the individual key relay, such as 126, and thereby prevents the selected operation taking place. Operation of unit. Upon operation of the last selecting relays 212, 413 the selected circuit breaker is operated in a circuit closed from one or other of the alternators 191, 192, which are adapted to generate currents of different frequencies. Since it is desired to " close " the circuit breaker the key 107 connects the alternator 191 over the contacts of key 105, relays 126, 140, 212, line c, contact of relay 413 to relays 734, 735 which respond and operate, a relay 737. This relay energizes a relay 613 over the contacts of relay 415 and thereby causes the energization of the " closing " coil of the current breaker 601. Supervisory signalling. When the circuit breaker moves to its "closed " position, relays 611, 612 are released to cause the momentary energization of relay 610 which locks up. When the relay ,612 is de-energized a su