Relay is NC instead of NO?

A relay I could have sworn I’d used before as NO is now behaving as NC. It’s the rayexelec LU5. Anyone have any idea what’s going on? A meter is beeping continuity when applied to the correct pins of the totally unpowered relay. Confused.

I guess you are measuring between COM and NO? Does the relay switch (clicking sound) when you turn it on and off? It might be damaged if it was working fine :wink:

Sorry in advance for the following questions :blush:

Are you sure you do measure the correct pins? These relays do have both NO/NC.

Have you given it a good whack. Maybe the contacts got stuck/“welded” :wink:

Try to switch it - can you hear the click?

My fate, always to be second :weary:

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If it is mechanical, perhaps it is truly stuck. Have you tried jolting it a bit? Does it work with power (switch from on to off)?

uggh, third.

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some cheap (not to impugn the Chinese manufactured) relays are so-called “Active Low”, some “Active High” bring to ground or 5V (respectively) to actuate the relay…

I’ve run across that…

The OP provided a link to the relay specs. The specs seems to be straightforward.

Yeah OK so it WAS stuck. A couple of flicks got it unstuck. But the really puzzling thing is it IS still behaving as NC, applying power opens the circuit! I could have SWORN it used to work the other way around! And it is soldered so it can’t just be the case that I’m using different connections today. Bizarre.

The datasheet for that relay seems to indicate which pin is NO.
Does the relay seem to be as the datasheet shows?