Associated Research Hypot II 4500D, Руководство по эксплуатации и обслуживанию

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INTRODUCTION
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However, specific products may be tested at much higher voltages than 2X operating
vo 1,000 volts. For example, a product designed to operate in the range between
100 to 240 volts, can be tested between 1,000 to 4,000 volts or higher. Most “double
insulated” products are tested at voltages much higher than the “rule of thumb”.
Testing during development and prototype stages is more stringent than production run
tests because the basic design of the product is being evaluated. Design tests usually are
performed on only a few samples of the product. Production tests are performed on each
and every item as it comes off the production line.
The hipot tester must also maintain an output voltage between 100% and 120% of
specification. The output voltage of the hipot must have a sinusoidal waveform with a
frequency between 40 to 70 Hz and has a peak waveform value that is not less than 1.3
and not more than 1.5 times the root-mean-square value.
Advantages and Disadvantages of AC Testing and DC Testing....
Please check with the Compliance Agency you are working with to see which of the two
type of voltages you are authorized to use. In some cases a Compliance Agency will
allow either AC or DC testing to be done. However in other cases the Compliance
Agency only allows for an AC test. If you are unsure which specification you must
comply with please contact our
CUSTOMER SUPPORT GROUP at 1-800-858-TEST
(8378).
Many safety agency specifications allow either AC or DC voltages to be used during the
hipot test. When this is the case the manufacturer must make the decision on which type
of voltage to utilize. In order to do this it is important to understand the advantages and
the disadvantages of both AC and DC testing.
AC testing characteristics
Most items that are hipot tested have some amount of distributed capacitance. An AC
voltage cannot charge this capacitance so it continually reads the reactive current that
flows when AC is applied to a capacitive load.
AC testing advantages
1. AC testing is generally much more accepted by safety agencies than DC testing. The
main reason for this is that most items being hipot tested will operate at AC voltages and
AC hipot testing offers the advantage of stressing the insulation alternately in both
polarities which more closely simulates stresses the product will see in real use.
2. Since AC testing cannot charge a capacitive load the current reading remains consistent
from initial application of the voltage to the end of the test. Therefore, there is no need to
gradually bring up the voltage since there is no stabilization required to monitor the