Patent GB-265661-A (GB)
Title: Remote control systems
IPC: H02J13/00
Filed: 1925-10-28
Abstract: 265,661. Coventry Automatic Telephones, Ltd., and Collyer, J. E. Oct. 28, 1925. Selective distant-control systems; tell-tale apparatus.-Relates to a system for the distant supervisory control of apparatus units, such as circuit breakers at a number of substations. The system is identical with that described in Specification 263,926 wherein a substation and a unit thereat may be selected by trains of impulses transmitted over common line wires and a supervisory signal is transmitted over a second group of line wires common to all the stations when a unit changes its condition automatically or under the control of an operator at the control station. To effect the control of a unit at a particular substation, three trains of impulses are transmitted. The first train selects the substation and locks out unwanted stations from the control lines and the second and third trains prepare the control circuit of the selected unit. The invention resides in the provision of impulsing devices at each station so arranged that the next impulse in the first or substation selecting train can only occur when the preceding impulse has been recorded at all the substations. The substations are arranged in parallel across the common conrol line wires 138, 139, 140 and the arrangement is such that varying times of operation and release of the impulse relays at the various stations do not affect the correct operation of the selective equipment. Fig. 2 shows the apparatus at the control station and Fig. 3 shows the equipment at each substation. Circuit breakers, such as 330, 331, may be selected by keys 101, 102, and selection is checked prior to operation of the selected unit by supervisory lamps, such as 103 - - 106 associated with the keys. When any particular key is operated, a corresponding relay in the chain 107 - - 112 is energized and impulses, the number of which is determined by the selected relay in the chain, are transmitted over the lines 138, 139 and are stored by similar chains of relays 301 - - 306 at each substation which are operated in succession to select the desired substation and lock out all unwanted stations. Two further trains of impulses are transmitted under the control of a sequence control relay chain 113 - - 118 to select the appropriate relays in the groups 325, 326 &c. and 327, 328 &c. and prepare a control circuit for the selected unit. Prior to operation, a supervisory check on the desired operation is transmitted in a similar manner over the lines 141, 142. If the correct supervisory lamp is illuminated by this checking signal, a further impulse is transmitted over the lines 138, 139 for causing the operation of the selected unit. Impulsing equipment. When a key is operated, the line circuit is closed over the lines 138, 139, relay 175 at the control station and relays 334 at all the substations. At each substation the relay 334 impulses the storing relay chain 301 - - 306 and operates an interrupter relay 344 which disconnects the line relay from the line wires and connects a holding relay 347 across the lines 139, 140. Although disconnected from the lines, the relays 334 are locked energized in local circuits including the contacts of the holding relays. When the line relays at all the substations are disconnected from the lines, the relay 175 at the control office is de-energized to energize the holding relays at the substations and a lock-out, relay 181 at the control office over the lines 139, 140. The lock out relay 181 maintains the impulsing circuit open until all the line relays at the substations are again connected across the lines 138, 139. When the relays 347 are energized the locking circuits of the relays 334 are opened and the counting chains 301 - - 306 are further operated to de-energize the relays 344. De-energization of the relays 344 disconnects the relays 347 from the holding lines and replaces the line relays 334 across the lines 138, 139. When all the relays 347 are disconnected the relay 181 at the control station is de-energized to complete the impulse circuit over the relays 175, 334 ready for a further impulse. In this manner each impulse is recorded at all the substations before a subsequent impulse can be generated. Releasing locked out stations. All unwanted stations are locked out after the receipt of the first impulse train by relays 367 which open the lines at the contacts 338. The relays 367, which lock energized over the back contacts 438 of the relays 347, also connect the relays 347 across the lines 139, 140. At the end of the transmission of the complete selecting signal, a relay 238, which is energized during impulsing, is de-energized to complete the circuit over the relays 347 at all locked-out stations and thereby de-energize the relays 367 to restore the line circuit. Specifications 185,722, [Class 40 (iv), Telephones &c.], and 268,515 also are referred to.