Run capacitor Start Relay. The start relay turns the compressor on when the in-unit thermostat calls for cooling, then disconnects power when the desired box temperature has been reached. These relays can be an electromechanical style, like a current relay, or a solid-state PTC that has no moving parts. Embraco designed a proprietary electronic.
What does a capacitor start relay do?
Run capacitor Start Relay. The start relay turns the compressor on when the in-unit thermostat calls for cooling, then disconnects power when the desired box temperature has been reached. These relays can be an electromechanical style, like a current relay, or a solid-state PTC that has no moving parts.
Why do start caps & relays burn up?
Start caps and start relays only burn up when the pump is starting or cycling too much. Burning up a start cap or pressure switch is just a first sign of how much damage cycling is doing and next to go will be the pump, tank bladder, check valve, or something else. The capacitor was shot.
Plan B: Turn off power and wait a day or two for the capacitor to self-discharge. The starting relay is a "potential relay" type. It is different from a typical N.C. or N.O. relay. It de-energizes the start windings in the pump at a precise amperage (or sometimes voltage) level passing through terminal #2.
What happens when a relay coil is removed from a motor?
Once the operating control opens and power is taken away from the motor, the motor speed will gradually decrease along with the BEMF generated. The relay coil will de-energize and the contacts between terminals 1 and 2 will return to their normally closed position as the motor comes to a stop.
If the start relay is defective, the compressor may run intermittently or not at all, and the refrigerator will not get cold enough. The start relay should be replaced if defective. Safely remove the start relay assembly. Test Start Relay with a multimeter. View the video above and verify if your start relay is functioning.
Why are potential relays referred to as voltage relays?
This phenomenon happens because the start winding usually has longer wire, smaller diameter wire, or more turns of wire, thus has a greater inductive reactance than the run winding. Because of this, potential relays are sometimes referred to as voltage relays since they rely on the BEMF or voltage that is generated by the motor for their operation.