"Alex Threlfall" wrote | My question (other than the comment about the lines into the pbx!) is | that on one of the extensions there's a bell box. Ideally, i'd rather | not waste an extension on it, and instead share it with the kitchen | phone, although as I type this I realise that it probably does actually | need to be on it's own extension (due to it needing to ring for external | calls only) so erm, well, does it need to be wired into a master socket | in some way?
Depends on the bell box. If it's an old one it may be low impedance and need conversion to high impedance. If you can see inside it you may see values written on the bell solenoids: 2 x 500 ohm is low imp, 2 x 2,000 or 2k ohm is high imp. If low imp, wire a 3.3k resistor (Maplin) in series with the bell solenoids. Disconnect the bells from any induction coils or circuit boards that may be in the bell box.
Take the bell solenoid wires to terminals 3 and 5 of a master socket on the extension. It can be shared with a phone subject to not overloading the REN of the PBX ringing generator.
If you are running short of extns you might be able to run the bell off the incoming line (that linebox you're going to fit, remember that BT line boxes are numbered backwards, so wire the bell into 4 and 2) and the bell will ring only on that line.
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