Compliance West HT-2000PR, Instruction Manual

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Additionally, the HT-PR may not recognize the failure. The test will continue for its
normal length of time, and the HT-PR may show a "PASS".
To allow the HT-PR to test equipment using a two wire power supply cord, the Ground Check
can be defeated by turning the rear panel Ground Check switch to the Off position. To remind
the operator that the Ground Check is not being conducted, both the green
Ground OK and red
Ground Open LED's will be lit continuously during the test. When testing with the Ground
Check switch in the Off position, the operator must ensure that the Test Return Lead is properly
connected to exposed dead metal of the equipment being tested for safety and to ensure that the
HT-PR properly reports all failures.
Leakage Test
The HT-PR leakage test uses a separate low-frequency circuit to check for excessive leakage
between primary power components and ground. There is not a specific leakage current level
pass/fail requirement at this time for most equipment, however, higher than normal leakage
current on a particular part may indicate an assembly or component problem in the primary
circuit.
The leakage current is also monitored by the HT-PR to ensure that excessive leakage does not
keep the tester from developing full voltage required for the high voltage test. The HT-PR will
provide full voltage at any leakage current level up to 20 mA AC (HT-2000PR & HT-3000PR) or
5mA DC (HT-2800PR & HT-3000PR). The leakage current trip level is adjustable on the rear
panel.
The leakage 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.
Excessive leakage current is not grounds
for failure of the dielectric withstand test. Leakage
current is a normal result of capacitance in the primary circuit between neutral or line conductors
and ground. (In dielectric tests of some larger electric motors, leakage currents of as high as 95
mA are considered acceptable by safety agencies.) However, leakage currents higher than
normally anticipated for a particular model should not be ignored. This indicates problems of
low resistance up to a short circuit between line/neutral and ground, and failures should be
investigated. Failure modes are discussed below.
If the green
Full Voltage LED light is on and the test continues, the leakage current is below the
limit set by the rear panel adjustment.
Sporadic Leakage Current Failures
If the red Excess Leakage LED light is on, the buzzer sounds, and the test is terminated, the
leakage current delivered to the equipment being tested was over the limit 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.