UNI-T AC Circuit Breaker Finder with Integrated GFCI Outlet Tester AC 90-120V USA Plug + Adjustable Sensitivity Beeper Indicattion+ Flashing LED Light

How should I adjust the sensitivity?

Adjust the sensitivity of the receiver to the minimum and keep slowly turning it up during the measurement until it can be accurately located to the break.

Does the power have to be on for the tester to work?

Yes, it must be powered on to test the circuit break, the receiver also needs to use a 9V battery to receive the signal, but we come with the package with a 9V battery.

The receiver just beeps at all the breakers. What should i do?

Turn down the sensitivity before using it, otherwise it will beep at any break until it is adjusted to a critical point, this critical point needs to be found by you, try it a few more times and you will find break.

Will it work if there is no electricity to the socket?

No, it will not work without electricity. The socket must be connected to 90-120V mains to power the transmitter inserted into the socket.