Circuit, Local

In telegraphy, a short circuit with local generator or battery included, contained within the limits of the office or station and operated by a relay, q. v. This was the original local circuit; the term is applicable to any similar arrangement in other systems. Referring to the cut, the main line circuit includes the main battery, E, Key, P, Relay, R, ground plates, G, G1. The relay magnet opens and closes the local circuit with its local battery, L, and sounder magnet, H, with its armature, B. The minor parts, such as switches, are omitted. IMG:8956969607833025625_124F90.jpg: Fig. 90. LOCAL CIRCUIT OF TELEGRAPH SYSTEM.