Some of our customers want a telephone bell instead of the standard DC buzzers available from the usual parts houses. We've packaged a small 12 volt DC ringing generator and a single gong ringer. The generator puts out 70 Volts AC at 20Hz which will drive a single standard telephone ringer. This package may used as a "drop in" replacement for a 12VDC buzzer: the button or computer output is connected to the ringing generator and the output is connected to ringer. The ringer we supply is a Comdial 20 WA (similar to those used in 2554 wall sets) although the C4A ringer used in standard 500/554/2500 sets will work fine also. The generator draws 135mA when on.
In a CMRI or similar control system, use a current sink output (CSNK, SMINI, DOUT) capable of 150mA at 12VDC. If you are using a cpNode without a CSNK, contact us and we can supply a 5V module.
Here's a quick connection diagram