View Full Version : power automatic transfer switch wiring

13-08-2014, 02:07 PM
did any one know how to wire this power relay which is used to
automatically switch power between generaator and the main electric line
here is a photo of the power relay



the current is 120 amp
the voltage is 220
coil voltage is 220

The Viking
13-08-2014, 03:50 PM
Well the initial thought is that the relay is 80A whilst the load is 120A so either a lager relay is needed or you have to wire it through a pair of contactors.

Normally I would expect the mains power relay to have the coil wired in to the L & N of the power supply, preferable in series with a true ON timer so that the mains have to be on solid for 30s-1min before the relay switches the load back to the mains supply again.

The load would then be wired to the common terminals with the mains wired to one side of the switched terinals and the generator supply to the other. (The mains supply should be on the side in contact with the common terminals whilst the coil is energised)


13-08-2014, 05:29 PM
the power relay i have is 120 A current
and the photo is for 80 A which i found in websites
and about wiring can u mark them on the photo

13-08-2014, 05:37 PM