Two wire control is usually used for a simple ON/OFF device such as a toggle switch, float switch, thermostat, or other device that would switch off of a high/low limit. See image below for an example of 2 wire control being used to pull in a contactor to start a 3 phase motor. When the 24VDC relay energizes, it pulls in the R1 contactor that feeds three phase power to the motor.
- Wire your trainer so that pressing Push Button 1 energizes the contactor. Then wire one of the contacts in on the contactor to turn on Light 1 whenever the contactor energizes. Use the above diagram to help you figure out how to wire it.