The indicator detects magnetic fields from AC sources such as solenoid valves and transformers. Place the indicator close to the AC device. The green-white disc rotates when the device is active.
The indicator also detects magnetic fields and rotation direction for certain circulation pumps. Place the indicator at the motor center. The green-white disc rotates in the same direction as the pump when the motor is running.
The indicator is equiped with a LED flashlight to provide additional lighting when needed.