Compliance West MegaPulse D5-PF, Instruction Manual

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Section 1
Introduction and Safety
An Introduction to Impulse Testing with the MegaPulse PF series tester
The impulse test is designed to simulate impulse surges which occur in everyday life due to nearby lightning
strikes, switching transients, and other high-frequency faults on the power distribution network. Impulse testing is the
fundamental method for empirical verification of the adequacy of insulation. Other methods of ensuring adequate
insulation (AC or DC Dielectric Withstand testing, measurement of over-surface creep age, through-air clearance, or
distance-through-insulation) are all extrapolated from the results of impulse testing. The impulse test is performed to
ensure that the insulation in question will be able to function properly when subjected to similar impulse surges in the
field.
Safety Precautions
The impulse withstand test can generate voltages in excess of 5000V peak at potentially lethal current levels.
Currents of as little as 5mA at 230 volts can cause death; the MegaPulse can deliver currents of more than 100 Amps
peak for very short time duration. The D5-PF 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.
CAUTION: Any use of this equipment other than as specified in this manual may result in a safety hazard.
Test Personnel
Personnel require special training to conduct the impulse 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 impulse test should be as remote as possible from normal production line
activities. Only personnel 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 an impulse test failure, it is
not safe to conduct impulse testing in combustible atmospheres. Make sure that the equipment is in a ventilated area
and that the rear fans are free from obstruction.
It is imperative that a good ground be provided to the MegaPulse tester. Before connecting the equipment,
ensure that the building wiring provides a low-resistance ground. If the MegaPulse tester is used on a high-resistance
grounding circuit, dangerous high voltages may be present to the operator.
CAUTION: Plug on power cord is disconnect device. 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.