CENTRAL BATTERY SWITCHBOARDS
C.B. lamp signalling switchboards of the standard type illustrated can he supplied for any number of lines and, when required, suitably equipped so that several units may be lined up together. The four sizes listed below provide capacity for up to 60, 120, 160 and 200 lines respectively. Any of these may be ordered equipped for serving a smaller number of lines than that for which capacity is provided, but in all cases the switchboards are fully wired so as to facilitate the addition of further apparatus as and when extension becomes necessary.
In systems where the loop resistance of any line, exclusive of the telephone, does not exceed 15 ohms, economy may he effected by employing switchboards which are not fitted with line relays. These are listed below in Series Nos. 6000-6300. Switchboards of the Series Nos. 6400-6700 in which line relays are employed, are suitable for use with lines up to 700 ohms loop resistance.
In each type the apparatus includes standard line jack mountings and lamp strips. The usual manual ringing and night alarm circuits are provided and the cord circuits are equipped with lamp signals giving double positive supervision.
Unless a hand combination is specified, the operator's set supplied consists of a head receiver and breastplate transmitter complete with cords and plug.
Cat. No. 6612 is shown pictured above.
Last revised: November 25, 2021