It can measure the insulation resistance of wire conductor and insulation layer, and also can measure the insulation resistance between wire conductors.

Under water

Measurement of insulation resistance by immersion in pre-grounded water for more than 1 hour with a DC voltage of 100V or more applied between the conductor and water for single-core wires, or between the conductor and water for multi-core wires, for more than 1 minute and less than 5 minutes.

Air

In air, measure the insulation resistance within 1 minute or less and 5 minutes by applying a DC voltage of 100V or more between the conductors.

However, for metal-covered parts, measure between conductors and between grounded metal outer layers.