I installed a relay for switching purpose With main supply and Generator. When there is no electricity from main supply relay change its coil to the generator. I want to know which will be the source of electricity when both the generator and main supply is providing electrical energy to relay.
The person installed a relay is electrician. I was preferring the Changover Switch (manual) for generator, main supply and cut out power (OFF). But he said after starting the generator you have to change the changover switch manually. By relay you only have to ON or OFF the generator and Relay will automatically trip the coil when there is main line power and if there is no main line power by starting generator it trip the coil and power will be of generator. I am confused that when both main line and generator are giving power to relay what will relay decide, which power it will transfer to home appliances.