Current detection switch / relay

[WHCreek]

Once upon a time I created a 20A circuit that had multiple outlets and at the end of the string I plugged in a refrigerator. Since that time I added a small chest freezer. After that came a larger chest freezer. If two motors start at roughly the same time I’m ok, but on the odd occurrence when three start at roughly the same time the breaker blows as you would expect.

Can someone point me to a device that can be installed at the outlet which can prevent a motor from starting if it detects that the current available is below a prescribed level?

 

[Bluejets]

The correct proceedure would be to call in a qualified electrician to access the maximum demand on the final sub-circuit and rectify as necessary.

 

[WHCreek]

Thanks Bluejets but that doesn’t answer the question. If I wanted to hire a professional I wouldn’t have posted on a forum. The question is, “is there a device”. That’s pretty much a yes or no. If it’s a yes, then a name would be handy.

 

[Harald Kapp]

I know of no such device. You can buy the opposite: extension cords that release auxiliary mains sockets ("slaves") only id the principal socket ("master") is active (plug load control).

You probably could construct such a setup from a smart home automation system. You'd have to provide each load (aka appliance) with a smart home controllable outlet (plug adapter) that also is able to sense when current is flowing (load is active) and signal this to the smart home controller. The controller in turn would have to be programmed to break the circuit for the other loads.
However, smart home automation doesn't work instantaneously. If the other loads turn on at the same time, while the automation system is still working on the relevant conditions to interrupt the other loads, your circuit breaker will still trip.

I know @Bluejets ' reply didn't answer your question, but it is imho the best advice you can get.