Hallo, I was interested in the above device. I was needing a relay that would be voltage sensitive switch. Basically I have some electric gates that will have lead acid battery backup. I want to set the system so that if the power goes off and the voltage drops below say 10v, I can use a relay trigger to open the gates and hold them open. Can the voltage trigger on this relay be set to a specific voltage in this way?

you 'could' do it this way but id suggest its a problematic way.

 

A better way would be to use a 240v relay and connect this to the incoming supply. When that opened it could open your gates straight away. If you would like a delay then id add a timer to hold off the relay.