In regards to the C30CNM mechanically held lighting contactors, what is the difference between 2-wire and 3-wire control modules?
For the C30CNM family of mechanically held lighting contactors, you need to select either a 2-wire or 3-wire control scheme based on the type of device or devices you plan on using to tell these contactors to turn on. If you are using a single contact that will close and stay closed when you want the lights to be on, such as in a photo cell or HOA application, that is 2-wire. If you have seperate signals for ON and OFF - meaning a hot wire that comes in to trigger the contactor to close and a second hot that will trigger the contactor to open (turn off), that is 3-wire control. See attached wiring schematics for further clarification.