Relays, Convention for terminals?
Relays often scare me a bit because they almost never
have a diagram on them about what their terminals
do--power, common, coil, normally-open, normally-closed.
And on the older units that have them, the schematic
is often unreadable or not there or not helpful.
Is there a conventional way that terminals are
numbered and assigned duties on relays so
that I don't need to depend on any information
at the unit? (If so, could you please tell me what
it was working.... played with it.... now its broke.... whats the going hourly rate for HVAC repair
Some relays have the 24 volt terminals soldered, and it's very easy with an ohm meter to figure out what is NO and NC, hope this helps.
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I have 4 different relay on my van and they all have some form of ID for each terminal.
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What about a nine pin socket relay? These are the ones that I struggle with.
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90-340 is stamped on the front.
Originally Posted by 5thRoot
The schematic I mean.
Originally Posted by socotech
I often replace the mushroom relays for the brown ones all the time. Much more easier to work on then the clear ones. Georgelass it just takes time to get use to them. i was the same way, bt after seeing it many times im not too afraid of them anymore. I hate the old sequencers that york has. those thing never have any scehmatics on them!! but from experience, i know what to look for to see what i need to replace those hunk of junk....
When you look at the see thru ones u can actually see the terminals if not most of them have a scehmatic printed on the side or front of them.
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This is a type 91 relay. The connection diagram is embossed into the plastic.
Originally Posted by 5thRoot
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