Compliance West HT-3000P, Instruction Manual

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Section 1
An Introduction to Dielectric Withstand Testing with the HT-3000P
The continuity test/dielectric withstand test is a production line test which is recognized
by safety agencies worldwide as a valid criterion of safe assembly of end-use equipment. The
test ensures that the primary circuit power and ground conductors were properly wired and
connected for safe operation. It also applies a high-voltage potential between power and ground
conductors to make sure that no unintentional leakage or arcing paths exist between power and
ground. The test consists of a ground continuity check, a leakage current check and a high
voltage check. It is non-destructive to the equipment under test, and can be accomplished in a
short time.
Safety Precautions
The dielectric withstand test generates voltages of up to 2000 volts AC or 2800 volts DC
at potentially lethal current levels. Currents of as little as 5 mA at 120 volts can cause death, and
the HT-3000 is capable of generating 20 mA AC at up to 2000 volts, and 5 mA DC at up to 2800
volts. The HT-3000 has been designed to minimize exposure to high voltages. However, the
potential for serious injury or death exists and personnel should be aware when they conduct this
test.
Test Personnel
Personnel require special training to conduct the dielectric withstand test. They should
understand electrical fundamentals clearly, and be aware that high voltage is adept and creative
at completing a path to ground. Instructions should include a warning against any metal jewelry.
Operators should not allow others in the testing area, especially when tests are being conducted.
Organization is to be stressed. The operator should keep the area free of unused leads and
equipment.
Testing Area
The area used for conducting the dielectric withstand test should be as remote as possible
from normal production line activities. Only personnel actually conducting the test should be
allowed in the area, and it should be taped or roped off to preclude casual entry by other
employees. In addition, the area should be marked "WARNING - HIGH VOLTAGE TESTING"
or the equivalent to warn others of the nature of the testing taking place.
The bench being used should be non-conductive, and any exposed metal parts should be
tied together and grounded. If a conductive surface must be used, it should be grounded.
Because of sparking during a dielectric test failure, it is not safe to conduct dielectric
withstand tests in combustible atmospheres.
It is imperative that a good ground be provided to the HT-3000P. Before connecting the
HT-3000P, ensure that a low-resistance ground is provided by the building wiring. If the HT-
3000P is used on a high-resistance grounding circuit, dangerous high voltages may be present to
the operator. In addition, the power to the Testing Area should be provided with an easily
reached shutoff switch which can be actuated by personnel outside the Area if needed.