By hvhipot 
The megohmmeter under HV Hipot Electric Co., Ltd. power can help many power workers conduct various power tests more conveniently.
Digital megohmmeter is a commonly used and indispensable instrument in industrial enterprises that use electricity as industrial power or energy, such as power, postal and telecommunications, communication, mechanical and electrical installation and maintenance. Suitable for measuring the resistance values of various insulation materials and the insulation resistance of electrical equipment such as transformers, motors, cables, etc.
The operation method is as follows:
1. Disconnect all power series resonances from the tested conductor or circuit. When performing these high-voltage tests, do not connect the voltage to the circuit.
2. Remove all wires to be tested. This means that any wire whose insulation value needs to be checked must be completely disconnected at both ends of the circuit. Bare copper ends are sometimes covered with wire nuts or tape. This can protect equipment or others from electric shock. When testing the motor, you must also completely disconnect all wires that supply power to the motor.
3. Connect one wire of the digital megohmmeter to the electrical frame or ground of the electrical system. When testing the motor winding, this lead will be connected to the actual metal frame of the motor.
4. Connect the other wire of the instrument to the bare copper end of the wire or one of the motor terminals. Check to ensure that the other end of the tested wire is in free air or covered with insulating material.
5. Open the instrument or start shaking the generator handle. High voltage may take 2 to 5 seconds to form within the wires or motor windings.
6. Read the table. A reading greater than 999 megaohms is almost the perfect resistance reading for wires or new motors. A resistance reading less than 1.5 megohms may cause problems with old wires or motors. In most cases, any reading between these values is acceptable unless there is a problem with these circuits.
7. Continue testing other wires or remaining motor terminals. Once the high voltage series resonance of the instrument stops, the wires or motor wires can be safely used.