Patent GB-277460-A (GB)
Title: Improvements in or relating to electric remote control systems
IPC: H02J13/00
Filed: 1926-07-16
Abstract: 277,460. Automatic Telephone Manufacturing Co., Ltd., and Remington, C. July 16, 1926. Distant control systems; tell-tale apparatus.- Relates to a system for selectively controlling and supervising apparatus units, such as circuit breakers, located at a remote station. Figs. 1 and 2 show the apparatus at the control station, and Figs. 3 and 4 that at the substation. Each circuit breaker, such as CB1, has at the control station a corresponding selecting key SKI, which, when operated, causes the transmission over two line wires 17, 18 of a train of impulses under the control of a step-by-step switch RLSB, Fig. 1. During the impulse train, a special impulse, the position of which in the train is characteristic .of the operated key, is transmitted over a third line wire 40 to effect the selection at the remote station. If the selection is correct, a checking signal is recorded at the control station, and the selected unit may then be operated by a manually operated key. When a unit changes its position the operation of supervisory signal transmitting means is initiated to transmit a code of impulses which is characteristic of the positions of all the circuit breakers. The inven tion resides in the provision of an auxiliary switch RLSC, Fig. 1, which is associated with the selecting keys and is operated simultaneously with the transmitted impulses until it reaches a position corresponding to the operated key. This arrangement eliminates the use of key relays. Selection of apparatus unit. When it is desired to select a unit for operation, the corresponding key SKI, SK2, or SK3 is operated in the appropriate direction to mark contacts such as 154, 155 on the rotary switches RLSB. RLSC, Fig. 1, energize the relay WR and the relay SA5 over the normal contact of the bank B3 of the switch RLSB. The relay WR connects battery across the lines 17, 18 and locks energized during the transmission of impulses over the wiper B5 of switch RLSB. The relay SA5 energizes the stepping magnets MB, MC of the rotary switches, which, however, are not operated until this circuit is opened. The relay SA5 operates relay SA4, which opens the circuit of relay SA5 to permit the switches to move forward one step and operates an impulsing lamp 11. Upon energization of relay SA4, the line circuit is opened at contact 103 to terminate the first impulse. When the switch RLSB is off normal, relav SA5 is directly connected to battery over wiper B3 and the switches continue to step forward under the control of the relays SA4, SA5, which are energized alternately. The impulses transmitted over the lines 17, 18 energize a relay LR, Fig. 4, at the substation, and thereby operate the stepping magnets MA. MB of the substation switches RLSA, RLSB in synchronism with the control station switches. When the marked contacts are reached, a circuit is closed over the wiper B1 of the control station switch RLSB, relay KR, and line wires 18, 40 for the relay COR at the substation. The relay KR prevents further impulsing of the switch RLSC, Fig. 1, and the relay COR transfers the impulsing circuit from the switch RLSB to the switch RLSC at the substation. Transmission of impulses is continued until the switches RLSB, RLSA at the stations are returned to normal. The switch RLSC at the substation then occupies a position complementary to the switch RLSB and the switch RLSC at the control station rests on the marked contact. The substation switches RLSB. RLSG complete the circuit of relay HR at the substation in series with a relay H1 at the control station. The relay HI illuminates a lamp such as L1 associated with the operated key to give a check on the selection, and the relay HR at the control station connects the relay 01, Fig. 5, across the line wires 18, 40. Operation of selected unit. If the checking signal is correct, the selected unit may be operated by depressing the master key OK, which energizes a relay N. The relay N closes the circuit of the relay 01 over the wiper C2 of the control station switch RLSC and lines 18, 40. The relay 01 energizes the operating coil of the selected unit over the lead C16 and wiper B1 of switch RLSB, Fig. 4. Restoration to normal of selecting equipment.. When, after selection and operation of the unit, the operated selecting key is restored, a. circuit is completed for automatically stepping the switch RLSC back to normal and the circuit of the relays H1, HR is opened. De-energization of the relay HR operates the relay BK, which closes circuits for stepping the substation switches RLSB, RLSC to normal. The relay 01 is deenergized, and on retracting its armatures permits the transmission of supervisory signals. Supervisory signalling. When a unit changes its position, due either to the operation of a. key or automatically under load conditions. a rotary brush momentarily energizes a relay RSRI, Fig. 3, over contacts such as 260, 261 and wiper D4 of switch RLSD. The relay RLSI also completes a circuit for relays SAR1, LLR over wipers D5, D1 respectively. These relays can be energized only when the switch RLSA. Fig. 4, is in the normal position and relay 01 is de-energized, that is provided no signals for selecting a unit are being transmitted and no unit is being operated. The relay SAR1 energizes the stepping magnet MD and a relay SAR2, which opens the energizing circuit of relay SAR1 to allow the switch RLSD to move forward one step. A relay CO1, energized simultaneously with relay SARI, disconnects the selecting equipment at the substation from the lines and connects thereto the supervisory signal transmitting apparatus. The relay LLR connects battery across the lines 18, 40 to operate a R1, Fig. 2, at the control station. Relay R1 causes the operation of relay SA2 to place relay R2 across the line wires 17, 18 and disconnect selecting equipment, Fig. 1, from the lines. Relay R1 also energizes a relay R3 which operates an alarm CBPB until the locking circuit of relay R3 is opened by the key 161. Relay R4 is also operated to illuminate a pilot lamp CBLP. Upon the first step of the switch RLSO at the substation, the relay LLR is de-energized, but the relays SARI, CO1 are energized over the wiper D5. The relays SAR1, SAR2 thus continue to interact to operate the switch RLSD, and each time the relay SAR2 is de-energized, an impulse is transmitted over the line wires 17, 18 to operate the relay R2 at the control station and thereby operate the switch RLSA synchronously with the switch RLSA. The circuit breakers are associated with the contacts of the wiper D1 in such a manner that circuit breakers occupying closed positions connect battery to corresponding contacts. Thus each time wiper D1 engages a marked contact the relay LLR is energized to transmit an impulse over the line wires 18, 40 and operate the relay R1. In this manner impulses characteristic of " closed " circuit breakers are transmitted over the lines 18, 40, whilst the impulses corresponding to circuit breakers which occupy the "open" position are sent over the lines 17, 18 during a cycle of operations of the transmitting switch RLSDWhen a circuit breaker is in its "open" position, the corresponding supervisory relay such as DR1 is locked energized and the green lamp GL1 is illuminated. When the relay R1 is operated in accordance with an impulse characteristic of the " closed " position of a circuit breaker, the left-hand winding of the relav DR1 is energized over the wiper A3 to neutralize the normal energization and illuminate the red lamp RL1. To signal the " open " position after the " in " position of a circuit breaker has been signalled, the relay R2 closes circuits over the wipers A1, A2 for the corresponding relays LR1, DR1 respectively. These relays lock energized and connect the appropriate gneen lamp in a flashing circuit comprising the interacting relays SA6, SA7. The lamp may be steadily illuminated and flashing terminated by operating the master key 162, which opens the locking circuit of relay LR1. In order to ensure that the correct signals are transmitted from the substation in the event that a circuit breaker immediately opens after operation, a relay X is energized as soon as the circuit breaker is moved to its closed position over contacts such as 222, 241 associated with the breaker, wiper C1 of switch RLSC, Fig. 4, wiper D2 of switch RLSD, Fig. 3. The relay X locks energized and prepares a circuit for relay Y. If the circuit breaker opens immediately after operation, the relay Y is energized over contacts such as 222, 223 to operate the relay RSR1. Battery is connected to the appropriate contact in the bank of wiper D1 of switch RLSD over wiper C1 of switch RLSC and contact 244 of relay 4. In this manner a supervisory signal of the " closed " condition of the circuit breaker is transmitted. Upon the completion of this signal the relay X is de-energized by the wiper D2 and transmission is again initiated to signal the " open " position, since relay RSR1 is held energized by relay Y. Repetition of signal transmission when switches become out of synchronism. If due to faulty transmission, the switch RLSA, Fig. 2, occupies an off-normal position at the end of supervisory signal transmission, the switch is automatically stepped to normal and a relay RP1 is locked energized to open the contacts 40 and prevent a selecting operation, to mark appropriate contacts in the banks of wipers B1, C2, Fig. 1, over the lead C23 and to initiate the transmission of a selecting signal at the contacts 142. The signal code selects a relay BR, Fig. 4, at the substation. When relay H1 operates after selection, a relay RP2, Fig. 2, energizes the relay N, Fig. 1, to complete the circuit of the selected relay RR. The relay RR energizes the relay RSR1 which initiates the transmission of supervisory signals. These signals are repeated until synchronism is again established. Specifications 252,231, 258,012, 258,178, 158,179, and