Network Relay Switch - NC800

I wanted to love this unit, I even got about 90% done writing the driver for it, but it freezes up consistently and just not worth it.

I am looking for a good/reliable 4-8 channel relay. Can be TCP/IP or zigbee/zwave. Any suggestions?

Don't have one, but it's in my cart...

https://www.amazon.com/gp/product/B091GS6J5W/

My experience with the 1-channel and 2-channel version of these is that the relay starts failing around the 2-year mark.

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I'm with @neonturbo on "inadequate snubber circuits on the magnetic coil side of the relay" because all the symptoms don't sound solidly relay related. The symptoms sound more like the relay is being told to do horrible things, and it is doing them :slight_smile:

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I also think @neonturbo hit the nail on the head with his hypothesis of snubber circuit inadequacy/failure. I wish I had saved the relays that failed.

I think discarding them was correct since the driver chip is probably what got destroyed.

I can't do much more than guess, but each relay has two surface mount components fed from the chip in the lower right of this image:

Screenshot 2023-10-07 at 11.29.10 AM

Without being able to see more of the circuitry traces, neither component seems to be across the relay. You'd expect to see a diode across the coil. Two devices in series is what I see and that wouldn't protect the chip from back emf. My guess is that it's a LED + resistor. Maybe I'll finish my purchase and grab a bag of snubber diodes :smiley:

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I got one, having trouble with it. it's pretty finicky...

I got mine yesterday and indeed there is no snubber circuit that I can detect. The diodes I ordered are not here yet so I won't power this up for a few days :smiley:

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