# Am I interpreting this relay pin diagram correctly?

I'm using a relay for the first time and am unsure if I'm interpreting the pin diagram given in the datasheet correctly:

I know a SPDT relay should have five pins:

NO (normally open)
NC (normally closed)
COM (where the power comes in)
Two coil pins (applying voltage across these activates the relay)


Here's my guess at what pins are which:

1   - COM
2,5 - Coil pins
3   - NO
4   - NC


That makes sense to me, but since I've never used a relay before I would really like to double check!

Yes, you are right.

Anyway if you have doubts:

• connect ohmmeter/continuity tester between 1 and 4 - if it shows zero resistance then this is the NC pin
• do the same for pin 1 and 3. You should get open circuit.
• between any coil pin and switch you should get open circuit.

I always do that, because I get confused with datasheets - top/bottom view.

Apply voltage to pin 2 and 5. Do the same test again. It should show opposite results.

• Am sure that you meant to type "Apply voltage to pin 2" and 5 (coil) :) – Marla May 15 '14 at 22:20