GB270325A - An arrangement for the distant control of switching devices - Google Patents

Abstract

270,325. Akt.-Ges. Brown, Boveri, et Cie, (Assignees of Oesterreichische Brown, Boverie-Werke, Akt.-Ges.). April 29, 1926, [Convention date]. Systems depending on two or more machines; switching-systems.-The operation of switches or a series of switching operations in distant substations, etc., is effected through a line or lines normally conveying indications of network conditions, such as voltage at a given point. The operated switches may initiate the operation of apparatus anywhere in the vicinity of such line or lines and not necessarily connected with the network. The existing indicating instrument is used to indicate in addition the progress of the controlled operations, such indication being limited to the duration of each operation. As shown in Fig. 1 the network A is connected by lines B (one of which may be an earth return) with a distant voltmeter V. One of these lines is taken through a relay coil Land through switches N1 - - Nn normally short-circuiting resistances O1 - - On in the control apparatus U. The voltmeter V has a short-circuiting pushbutton P which is held closed by a coil Z after operation to initiate the distant switching by the current resulting from short circuiting the voltmeter. This current closes a switch M in the distant control apparatus which connects a motor H to a source such as the subsidiary transformer F energized from the feeder C. The motor H drives a controller drum J which, for example, causes the operation of mechanism closing the main switch D and initiating the starting of subtraction machinery. A cam K holds the switch M closed whilst the control drum is moving between positions so that the coil L need not remain energized and a cam K, first opens the short-circuit to release the push-button P and allow the voltmeter to show its normal reading and then switches a resistance 01 in series to cause the meter to give reduced readings, thus indicating the progress of the switching operation. The termination of the operation is indicated by the return of the voltmeter to normal readings, caused by the cam K reclosing the switch N1 when the first controller position has been reached. At this point the cam K allows the switch M to open. The push button P is released on the first operation of the switch N1. By using graded resistances 01 - - On the voltmeter may be caused to register on different portions of the scale for successive switching operations each of which may take place in turn on successive operations of the button P. The resistances may be electrically controlled from the controller drum. The Specification as open to inspection under Sect. 91 (3) (a) states that selective arrangements of known kind may be used in conjunction with the controlling apparatus. This statement does not appear in the Specification as accepted.