Patent GB-264235-A (GB)
Title: Improvements in electric remote control and indicating systems and apparatus used therein
IPC: H02J13/00
Filed: 1925-10-14
Abstract: 264,235. Western Electric Co., Ltd., (Bell Telephone Laboratories, Inc.). Oct. 14, 1925. Selective distant-control systems; tell-tale apparatus.-In a system for controlling and supervising from a remote point the operation of a number of apparatus units, such as power switches, at a substation, wherein each unit is selected and operated by a characteristic code of impulses transmitted by an impulse transmitter of the ordinary interrupter type and the positions of the apparatus units are indicated at the control station by pairs of electric lamps, the supervisory indications may be checked upon the transmission by another impulse transmitter of a code which causes the operation of the signal transmitting apparatus at the substation. Fig. 1 shows the apparatus at the control office and Fig. 2 shows the substation apparatus. Impulse transmitters, such as 88, are provided at the control office for operating the units, e.g. the power switches 8, 9 at the substation, and the positions of each unit are signalled at the control office by pairs of lamps such as 67, 68. The control and signalling operations are effected over lines 5, 6, the line 7 being used for locking out other sub-stations on the lines during a signalling operation and preparing the signalling circuit at the control office. The apparatus units and supervisory signals are selected by characteristic numbers of impulses which operate selectors of the type described in Specification 117,170. Operation of circuit breaker. Assuming it is desired to close the switch 8 at the substation, the corresponding impulse transmitter 88 is operated to energize, through the wheel 88 and contact 90, a relay 140 which energizes a relay 89 to connect the lines 5, 6 to the battery 93 and by means of a relay 142 disconnects a charging generator G from the battery. Upon continued operation of the impulse transmitter, intermittent contact is made at the contacts 90, 94 and the relay 84 is pulsed to send a characteristic number of impulses of alternate polarity over the lines 5, 6, to operate a selector 148, Fig. 2, until contact is made with the contact 149 and the upper winding of the relay 150 is energized to operate the closing coil of the switch 8. Supervisory signalling. When the switch 8 is operated, the contact arm 13 is moved into engagement with a contact 15 to energize the left-hand winding of a relay 57 over a circuit extending from the battery 14, conductors 98, 106, contact 119 of a relay 34, lead 99, contact 119<a> of relay 34<a>, lead 101, contacts 13 15, lead 10, contact 102, lead 103, and relay 57 to battery 14. The relay 57 closes the circuit of a relay 59 at the substation and a relay 87 at the central station over the lines 6, 7. The relay 59 opens the line 7 at the contact. 92 and thereby prevents stations, such as C, on the lines more remote from the control office from signalling. Relays 60 at substations nearer the control station are also energized over the line 7 to prevent these, stations from signalling while the lines are being used by station B. The relay 59 also operates a motor 27, which drives a shaft 26 on which are frictionally mounted gear wheels 28 individual to each apparatus unit and adapted to operate the shafts 30, 31, which carry impulse transmitters such as 47. adapted to transmit signals indicative of the position of the associated unit. The shaft 26 also carries cams 49, 50 arranged so that the .contacts 53, 54 are closed successively, to prevent confusion of signals if two or more units operate simultaneously. The contacts 53 close the circuit of the relay 34 which withdraws a latch 38 from a pin 36 and allows the shaft 30 to rotate. The relay 34 also attracts its right-hand armatures to close locking circuits for itself and the relay 57 and lock out at the contacts 119 the signalling apparatus associated with the other units at stations B. When the shaft 30 rotates, the transmitter 47 sends impulses over the lines 5, 6 to operate the relay 85, the circuit of which is prepared by the relay 87, and consequently the relay 84. The relay 84 sends impulses over the leads 77, 78 to step the arm 62 of the selector 61 on to the appropriate contact 80. Each supervisory signal impulse transmitter is constructed so that the characteristic code of the " open " or " closed " position of the unit is transmitted during half of a revolution and the arrangement is such that at the end of either code transmission an additional impulse is transmitted to effect the release of the selector 61. The selector 61 has a series of pins 90 which contact with an arm 79 in the circuit of a slow-acting relay 141. During the stepping operation, the time of contact between the pins 90 and the arm 79 is not sufficient to allow for the operation of the relay 141, but the last impulse of the train is of sufficient duration to permit the operation of the relay 141 and the energization of the selected polarized relay 63 which short circuits the green lamp 68 and illuminates the red lamp 67. After the shaft 30 has completed a quarter of a revolution the contacts 102 are opened and the contacts 113 are closed to prepare tha circuits for signalling the " open " position of the switch 8. At the termination of the signal transmission a cam 48 operates the contact 111 to open the locking circuit of the relay 34 which releases the latch 35 and brings the shaft 30 to rest. The relay 57 is deenergized to stop the motor 27 and open the circuit of the relav 87 at the control office. Checking. The operator at the control station may check the position of the apparatus at the substations to determine if the supervisory indications are correct. An additional selector 37, provided at each substation, controls relays such as 39, 40 individual to the power switches in such a manner that the connections of the signalling apparatus at the substation are changed in a manner similar to that which takes place when a power switch is operated. The selector is stepped forward by an impulse transmitter at the control office until the arm 96 engages a contact 97 when a relay 38 operates the relays 39, 40. The relay 39 reverses the connections to the contacts 13, 15 and indicates the operation of the signalling apparatus in a manner similar to that previously described. Upon the completion of the events associated with the actuation of the relay 39, the shaft 30 is brought to rest and the contact 119 is again closed and a similar series of events occurs in association with the switch 9, since the relay 40 is already operated. When the events controlled by the relay 40 are terminated the relays 39, 40 are de-energized and since the relation between the contacts associated with the power switches and those associated with the discs 46, 45 is now reversed the same series of events is restarted. Upon completion of this second series the discs 46, 45 are returned to the positions occupied prior to the checking operations. Hence if the supervisory lamps show the correct indications, they will, when the checking transmitter is operated, change to the opposite indication and then resume their original indication. If however, the lamps show an incorrect indication, a correct indication will be given upon the second operation of the impulse transmitters. The selector 37 may be omitted if space contacts on the selector 148 are available.