Patent GB-369570-A (GB)
Title: Improvements in or relating to remote control systems
IPC: H02J13/00
Filed: 1930-12-19
Abstract: 369,570. Electric signalling and remote control systems. AUTOMATIC ELECTRIC CO., Ltd., (formerly AUTOMATIC TELEPHONE MANUFACTURING CO., Ltd.), Strowger Works, BURNS, G. A., 4, Lucas Estate, Thomas Lane, Knotty Ash, and GUNNING, P. F., 10, Fairfield Street, Fairfield, all in Liverpool. Dec. 19, 1930, No. 38386. [Class 40 (i).] In a remote control and/or supervisory signalling system for a number of substations connected over individual pairs to a control station, selection is obtained by the transmission of two equal trains of a fixed number of impulses, divided to provide selecting and checking components. The two parts of each train are of different polarities. Immediately a piece of apparatus has been selected, its indication on the mimic diagram is checked. Operation of the selected unit is effected by the movement of a special key, a second operation of which initiates the transmission back of the meter reading associated with the selected unit. Automatic operation of a remote unit initiates a transmission back of supervisory signals to correct the relative indication and suitable alarm signals are brought into operation. During the transmission of supervisory signals the apparatus moves at a fixed rate over unaltered signals and at a much slower rate over those signals which require adjustment. Fuse alarm signals are provided. As described the system caters for a maximum of 100 units at each substation. Selection of remote unit. A key is provided individual to each apparatus unit which is wired to bank 1a or 1b of the 25 point switches AFS, BFS which have " on " and " off " wipers moving over 50 consecutive contacts. If apparatus unit 74 is to be selected key 74SK (which is similar to 51SK but is not shown) located in the mimic circuit diagram is operated to either its " in " or " out " position. Earth is removed from the relative contact in 1b and CO operates. Relay B pulls up, locking CO over 1c of PSS, K pulls up and BFS searches for the marked contact. When this is reached B releases and SL and F pull up. Wipers 2b to 5b of BFS mark contacts in 5c of PSS relative to the selected unit. Relays F and SL complete a circuit for E and E and F interact at a rate controlled by the slug on F, magnet PSM operating each time E pulls up to step PSS. The second winding of E is shorted over 4c of PSS when this switch is in its home position so that the first pulse is slowed to enable the apparatus at the remote point to be satisfactorily homed. Relay IN operated when SL pulled up connecting +ve and -ve potential to the A and B wires respectively (Fig. 6), and this circuit is broken each time E de-energizes to transmit pulses to the remote station. Lamp IML (Fig. 1) flashes in synchronism with the pulses to show that selection is proceeding. At the substation polarized relay PX responds to the impulses and energizes P which repeats the impulses to TRM (Fig. 3) which steps the tens responding switch TRS. Relay S is also energized by P and holds energized throughout the train. SR pulls up followed by HS and HR, the latter relay opening the homing circuits of the substation switches. As unit 74 is to be selected the eighth and sixteenth terminals on 5c of PSS are marked with +ve potential and when the eighth terminal is reached, relay OUT operates and locks over 4c of PSS, releasing IN, reversing the polarity on the A and B wires and completing a circuit, over 3c of PSS and 10, to VM of the bidirectional switch with wipers 1g to 6g (Fig. 4). The impulse train continues but at the substation NX responds instead of PX, energizing N which, as TRS is off-normal, repeats the impulses [over 2d and 2e (Fig. 3)] to the vertical magnet IVM of the bidirectional switch with wipers 1f to 6f (Figs. 8 and 7). The remaining four digits of the first train of eleven are thus effective in raising the wipers of the bidirectional switches at the main and substations. When the wipers of PSS arrive at the 12th contact the locking circuit of OUT is opened at 4c and this relay relapses allowing IN to re-operate. The direction of current flow over the wires A and B is thus reversed and PX again responds to the impulse train but as the substation bidirectional switch has moved off-normal springs 3N1 have changed over and the train is repeated by P to URM to step URS. When 5c of PSS reaches the sixteenth contact OUT again energizes to reverse the polarity in the signalling circuit as before. The remainder of the train is repeated by NX to N, and, as URS is now off-normal, IRM responds and steps the substation bidirectional switch in a rotary direction. Similarly at the main station, the impulses are repeated over the second set of commoned contacts of 3C to RM and the main station bidirectional switch moves in synchronism. When PSS reaches its 23rd contacts SL, E, F and OUT release and the lamp IML ceases to flash. Checking selection and indicator position. Two series of eleven impulses each are always transmitted and the wiring of banks 3e, 3d and those wiped by 5f and 6f is such that when the full complement is received a series circuit is completed over these wipers and conductor 12 for HD. When S falls away, at the end of its slow period, HD operates and, during the succeeding slow period of SR, H energizes. The A and B wires are thus extended to operate SP, which holds H. Wipers 1f to 4f of the substation bidirectional switch connect to the apparatus selected, the indicating portion of which comprises a mechanically latched relay combination L, UL. As shown the circuit breaker is " out " and consequently the contacts of L are open so that 2f does not find positive and RV (Fig. 2), which is connected to this wiper over 14, does not energize. Under these conditions the polarity on the A and B wires returned to the substation on the operation of H energizes polarized relay 1 B. Relay O (Fig. 6) pulls up and completes a circuit over 16, 5h, 17, 5g and 18. If the indicator corresponding to the selected breaker is in its correct position this circuit is ineffective, but, should the armatures of 1L be locked up, 1UL is energized to correct the indication. Had the circuit breaker at the substation been " in," relay RV would have energized over 2f and a pulse of opposite polarity would have been returned to the control station. At the control station a circuit is completed over 19, 3g and 20 to energize R and white lamp WPL lights, over 4g, to indicate that selection is complete. Operation of circuit breaker. To operate the unit key OPB, individual to the selected substation, is operated and OP energizes, in parallel with WPL, and locks. As SL has de-energized either relay IN or relay OUT pulls up over 2g or 1g from contacts of 74SK1 or 74SKO. The circuit breaker is to be moved " in " so relay IN pulls up. OP breaks the loop over the wires A, B and completes a circuit for slow-operating relay BK. As the loop is opened SP at the substation releases and H falls away to reconnect NX and PX to the control circuit. When BK pulls up a pulse of " in " polarity is connected to the wires, PX operates, P pulls up and HD energizes, connecting potential to bus-bar 1BB. The righthand coil of INS energizes over If and moves the circuit breaker into its " in position. Had 74SK been moved to its " out " position the polarity over the control wires would have been reversed, NX and N would have responded and the left-hand coil of INS would have been operative. The latching relay L operates and locks mechanically and, as HD is up, RV pulls up over 14, 15. When the key OPB is released, OP de-energizes and PX, PS and SR fall away. During the slow period of SR, relay H reoperates and the signal back circuit is completed as before described but, as RV is now energized, the pulse is of reversed polarity and 1A pulls up. I pulls up and energizes 1L over 21, 22, 23. Relay 1L locks mechanically, changes the indicator from the green lamp GOL to the red lamp RIL and prepares the circuit to the mechanical meter MM. Relay R releases and WPL relights. Should the key OPB be prematurely released slow relays BK and L hold the circuit until the latching relays have been adjusted. Meter reading. Those circuit breakers provided with metering equipment are fitted with a relay M connected to wiper 4f and conductor 15. When the contacts of L are operated M pulls up preparing circuits to LF (Fig. 8) and to the pull down coil PDC of the appropriate meter CNM. CNM is of the type described in Specification 356,211. When the meter reading is required operating key OPB is reoperated and, as before, PX and P respond. LF pulls up and coil PDC pulls down the needle of CNM to mark a particular contact. At the control station BE (Fig. 6) operates over 22 and locks. MM does not energize in this circuit. When OPB is released PX, PS and SR fall away and H reoperates. As LF is back PU energizes in series with MPM and short circuits itself to allow MPM to pull up. MPM and PU interact slowly and MPS steps round its banks, the impulses being repeated by PU over the wires A, B. As RV is operated, these pulses energize 1A and I repeats the pulses over 22 to operate MM which moves the pointer 25 over a suitably calibrated scale. When 1h reaches the marked contact W pulls up, opening the circuit of PU and releasing RV. The current flow in A, B is reversed, 1 Band O operate and the circuits remain in this position until the key 74SK is released. Relays K, BE, RL, G, 1B and O fall away. G releases, completing a circuit for ZM to release the bidirectional switch and PSS homes over offnormal contacts 2N2. When K releases MM steps on to its normal position. At the substation SP releases and H, HS, HR, HD and LF fall away. HR completes homing circuits in turn for URS, TRS and MPS and then 1ZM operates to restore the bidirectional switch to normal. Supervisory signals. Should a circuit breaker change its position automatically, as SR is de-energized, RSR (Fig.