Has anyone here powered a sensor from the DC output of this unit? There is a single grey wire marked as 9V DC but no other point to complete the circuit. I’d like to power a buck converter to feed a 3V door contact sensor without needing to change batteries. Seems it’s probably just a simple half rectified output on that grey wire though…
That is an equivalent output signal wire to the red wire on AC smoke detectors, when it receives the same signal on the input red wire of the relay. It can be used as the power source for a pull for fire switch which loops back to the red wire to trip the alarms, or as a loop back to the red wire when the relay AC power is tripped by a different kind of alarm or relay. Max output is 5ma…
Thank you. I cut open the unit out of curiosity and that all makes sense now that I see it too. A shame, I had hoped there was a DC output for another reason with a proper supply. Oh well, made my own solution in the meantime.