I have a field device that uses normally open switches that has an optocoupler for each of the inputs for isolation. The field device is powered by a 3.3 VDC lithium battery. The other portion of the circuit also is tied to a 24volt DC power supply to drive a bulb. The commons of the battery and the power supply are tied together.
My issue that I'm having is that I have a 6 of these that are driving six lamps and it seems that I'm getting a power surge that turns on all 6 of these devices. I think it might have something to do with commons tied together and fluctuating the ground high and turning on the optocoupler and activating my lamps.
Attached is the major portion of the circuit.