MIT30 high-voltage insulation tester

The MIT30 high-voltage insulation tester is housed in a rugged case (IP67 rated when closed and IP52 rated when in use), designed for field use in acceptance and maintenance testing of switchgear and transformers.

The instrument offers continuously variable output voltage from 0-30 kV with test currents up to 330 µA. The maximum output voltage and current can be achieved simultaneously, which allows fast charging of capacitive test pieces, thereby reducing test times.

Digital readouts display the test voltage and current continuously during a test, with ±1.5% accuracy. Voltage readout resolution is 10 V and current readout resolution is 100 nA. A ‘current-guard’ circuit minimises the influence of external effects such as surface leakage to enhance testing accuracy.

Operator safety features include zero-start interlock; cable interlock with LED indicator; short- and open-circuit protected outputs; user-adjustable current trip that can be set at 0-360 µA; to protect the instrument from flashovers and possible damage; ionisation detector that gives an audible indication of any electrical discharges that occur while the test is in progress; and a heavy-duty discharge assembly that rapidly discharges the power supply and test piece to minimise the risk of shock hazards.