Electricians sometimes need to check the amperage on a wire without disconnecting from a circuit feed and clamp-on amp probes are the answer. These amp probes come in either an analog display or a digital display. By simply pressing the button on the side of the tester, the loop at the top opens and can be easily placed over a wire in a junction box or electrical panel. This is an easy way of checking the current value running through a wire at any given time.
You'll notice the amp probe also has connection holes at the bottom. This is for checking the load with test leads when breaking the circuit connection. Some amp probes have a dial to set the range of amperage in order to get a more accurate reading. By using this electrical tool, you can find out if a wire is drawing more amps that the electrical wire is capable of carrying. Electrical overloads can cause electrical fires. This could result by having too large of a fuse or circuit breaker on a circuit wire. By following some electrical safety rules and using an amp probe to check the amperage on circuits, you'll be able to keep your electrical system purring like a kitten.