Non-Invasive Current Sensor - monitor power into house (on/off only)

Components & Accessories Power
1

Hi - I am looking to set up a current monitor to test if power is coming into the house or not to determine when utility power is restored after an outage. I am having a power inlet and interlock switch for a generator installed by an electrician and while he is in there, I wanted to have him clamp on a non-invasive current sensor on the power lines to the circuit panel. The objective is to then connect to a Raspberry Pi that will monitor if power is flowing and if so, send me a message once utility power has been restored. With an interlock, the entire panel is either on utility power or on generator power, and if the generator is running, I won’t have a lamp or anything turn on to let me know power was restored. So, the sensor has to be attached on a wire where power comes into the panel vs clamping onto one of the downstream breaker lines that would be lower amperage. My questions are:

1.) The sensor I am looking at is rated for 30 amps, but there will be more than that coming from the utility (100-200 amps). Will this sensor still work for just monitoring current Y/N or will it get “fried” from the higher amperage? This is the sensor I found: Non-Invasive Current Sensor - 30A (https://www.sparkfun.com/products/11005)

2.) If this sensor would be damaged, or would not work in this application, are there sensors with a higher amperage rating available (100-200 amps)?

Thank you for any help you can provide!

2

It might work, but I’d be worried about it potentially overheating - maybe take a look at something like https://www.amazon.com/Current-Sensor-T … 6541&psc=1 ?

3

Nice, that looks much better! Probably easier to deal with the wires than the pin jack also. Thanks for the suggestion!

4

A current sensor will tell you if current is flowing from the utility, it won’t tell you if utility power is available. In your case no current will flow from the utility because your transfer switch has the utility disconnected from any load.

A relay with a 120 or 240 volt coil would be better, that will open or close a switch you can monitor when the utility power comes back on.

5

Your best bet would be to have an electrician install a relay or outlet prior to the main breaker. It would need a breaker or fuse for protection (tap rules). Note that since those lines can’t be shut off without pulling the meter, it isn’t a DIY task.

Another possibility would be to modify a non-contact voltage detector such as https://www.fluke.com/en-us/product/ele … uke-1ac-ii.

6

If you’re looking for power restoration status, wouldn’t a simple voltage detector at the service entrance be easier?

7

Thanks all for the suggestions. In talking with the electrician, he mentioned a detector he has used in the past also that has an alarm on it. That might be an easy route also. The Raspberry Pi solution may be more elegant than I need but wanted to check into it.