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kewtechcorp.com
Insulation
Caution
Measurements must only be carried out on de-energized circuits.
If the tester is connected to a live circuit (25V or greater), the LED will flash red and the hazard
buzzer will sound. Your KT63 PLUS is fully protected and measured RMS voltage will be displayed
on the secondary/lower display. Further testing after this point will be inhibited. To resume testing,
disconnect the test leads and isolate the circuit.
All equipment and appliances should be disconnected from the circuit under test. Attached
equipment may be damaged by the higher voltages applied during testing and may return an
artificially low test result.
There may be capacitance on the circuit being tested after you have a measured result. Your tester
will automatically discharge this, do not disconnect the test leads or change tester function until
auto-discharge has completed.
Warning
Do not touch the ends of the test leads while on the Insulation test functions as they are energised.
Results of measurements can be adversely affected by impedances of additional operating circuits
connected in parallel or by transient currents.
Principle of Measurement
During insulation measurement the tester generates a high voltage internally. The positive side
of this is connected to Brown (VΩ) lead causing a very small current to flow through the external
insulation resistance, Green (COM) lead, meter resistance and finally back to the negative side of
the HV generator.
The current and voltage are measured as shown
and the external resistance calculated and
displayed.