Compliance West HT-3000P, Instruction Manual

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If the green Full Voltage LED lights and the test continues, the leakage current was
below the amount set by the rear panel adjustment.
Sporadic Leakage Current Failures
If the red Excess Leakage LED lights, the buzzer sounds, and the test is terminated, the
leakage current delivered to the equipment being tested was over the amount set by the rear panel
adjustment. If other equipment of the same type routinely passes this test, there may be a
problem with the primary circuit of the example being tested. The unit should be checked and
reworked if necessary.
Chronic Leakage Current Failures
AC Dielectric Withstand testing charges all primary circuit capacitors connected line to
ground or neutral to ground. The current flowing through these capacitors is defined as leakage
current. If almost all examples of a model of equipment are not passing the leakage current test,
we recommend that the leakage current limit be increased by resetting the leakage current level
on the rear panel to a higher level.
If the leakage current adjustment of the HT-3000P is set to 20 mA AC and almost all
examples of the model being tested are still failing, the primary circuit capacitance of the
equipment may be too high to allow the AC dielectric withstand test to be used. This is due to
the AC voltage charging all capacitors connected between primary voltage and ground. If the
overall value of these capacitors cause a leakage current of more than 20 mA to flow at the
desired test voltage, the HT-3000P cannot generate full voltage, and cannot successfully conduct
the AC dielectric withstand test.
However, a DC dielectric withstand test is acceptable for most categories of equipment
and will not charge the primary circuit capacitors. The DC test can be conducted by switching
the front panel switch to DC. If the problem was due to high leakage current, the test should now
be successful.
High Voltage Dielectric Withstand Test
This test checks for insulation system breakdowns between the primary and ground
circuits. The HT-3000P uses a separate high-frequency transformer circuit to check for and
detect arc breakdowns.
The dielectric withstand test is conducted by shorting the line and neutral conductors of
the power supply cord and applying high voltage between them and the exposed dead metal of
the chassis of the equipment being tested. The duration of the test is controlled by the test time
control on the back panel. The test time is counted from the time the
Full Voltage LED is lit to
the completion of the test.
If the green Hipot Pass LED lights, the test cycle has been successfully completed. The
equipment under test is in accordance with the preset test parameters. The HT-3000P is ready to
test the next piece of equipment.