24v relay back up schematic

Dear everyone!

I’m trying to imagine a simple schematic which alternates between a primary and secondary power source via a 24v relay.

The idea is to power up a 24v load (200mA) with a 24v relay which also energize the relay so when primary source goes offline it will switch to secondary 24v source.

Primary source will be a 24v transformer plugged in at the wall and secondary will be a 24v battery bank.

Many thanks,

by Cornelius123
March 22, 2019

1 Answer

Answer by mu34tant

24v double pole double throw relay. put your backup on the normally closed side. when relay is energized by primary the output from the normally open side will power load. when relay is de-energized the output from nc side will power load. put a small diode reverse biased across coil.

+1 vote
by mu34tant
March 30, 2019

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