5X840 Relay Knowledge Needed

[Richard D]

I have a remote control gate that my friend built before I bought the house from him. He has since passed, so I can't ask him. There are three relays, they all LOOK the same. I can't make out the numbers on all of them. I have a couple extras in the garage. Of the three I can read, they are all 5X840s, with a different letter on the end of the part number. One is 5X840O(letter O), 5X840N, and 5X840, no letter. The gate seems to not care which relay goes in there, I want to replace them all, is there a major difference in 5X840 relays? I am completely a numbskull when it comes to electrics, I don't even know what the relay does!

 

[aandpdan]

A relay is basically just an electrically operated switch. A small control voltage can switch a much larger output.
Your 5x840's are available. It's a 24 volt relay, 3 poles, double throw.
Just watch the contact ratings.

 

[nadogail]

A quick Google search tells me that 5X840 is a general purpose 11 pin plug in relay with a 24 volt coil and rated to switch up to 277 Volts at 10 Amps. They are commonly available from several vendors and you can expect to pay around $20.

The suffixes may indicate the presence of a mechanical indicator ("Flag") or different manufacturer.