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Protect against overvoltage with Shelly 3EM

Andrei S

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I bought a Shelly 3EM to monitor my energy consumption and use it as an input for a contactor to cut off the power whenever the voltage move above a certain level. 

I also bought a 32 A three phase contactor that I want to use combined with contactor control. Now... I've measured the voltage between I and O pins, but none of the gives me 230V. 

How can I connect the 230V contactor coil to my Shelly 3EM? Also, that turn on/turn off button should make it turn on and off contactor coil,right?



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Andrei, Pins I and O of Shelly 3EM are the contacts of a relay! Thus, you’ll have to connect the live wire to pin I, one end of the relay coil to pin O and the other end of the coil to neutral. Don’t forget to install a snubber (R/C combination) across the relay coil!

Good luck, Thomas 

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