GB190013539A - Improvements in or connected with Current Arresters and Alarms. - Google Patents

Abstract

13,539. Lorrain, J. G., [Burns, P. C.]. July 27. Lightning-arresters.-Current-arresters, in which the circuit is broken by the heating effect due tu an excess of current such as described in Specification No. 13,538, A.D. 1900, are provided with additional contacts by which an open-circuit alarm is closed when the guarded circuit is open. Fig. 4 shows diagrammatically a local bell circuit closed by the spring F and contact k on the release of the plug D. Normally the plug D rests by its insulating-end k<1> on the spring F, and maintains the alarm circuit open. In a modified form, the spring B is provided with a forked free end, which on release contacts with two insulated blocks in the alarm circuit. In this form the earth connection l may be omitted.