I have a very specific use case, but I’m not sure what this would be called, so I’m having trouble figuring out if what I want actually exists.
I have a building with a dry fire sprinkler system, meaning the pipes are kept filled with compressed air. The air compressor is hard wired. Of the circuit breaker trips for some reason, the system could slowly lose compression, which “could be bad” because the system would fill with water even though there’s no fire.
What I want is a sensor that will alert me via Home Assistant if the power to the compressor has failed (e.g., the circuit breaker has tripped). Because the air compressor is hardwired, I would prefer to have something that does not have to be put in line. Like something that clamps on to the electric cable and has its own independent power source.
This worked well for me. https://www.aliexpress.us/item/3256806780178387.html
It is current sense, so you would look for it to run every so often.
If you want to measure voltage, any ESP32 and espHome and a wall wart power supply connected to the same circuit as a sensor would measure that, but it would have to be connected on the compressor side of any circuit breaker.
Exactly, amp sensor. It doesn’t give you information if circuit breaker has tripped. It can sense if current is flowing, in your case if compressor is running.
Well that’s an interesting point to think about. It’s a brand new compressor, and it only needs to run occasionally, so I wasn’t worrying about that. But of course you are correct that might be a more complete solution.
This is what I’ll probably do if there isn’t a similar live voltage sensor. My only issue is the compressor only needs to run occasionally, so I wouldn’t necessarily know right away if the circuit had failed.
I know that contactless live wire sensors exist because I use one of those pen-style sensors for electrical work. I was just hoping someone had created a smart version.