voltage shall be raised from zero to the specified value as uniformly as
possible, at a rate of approximately 500 volts (rms or dc) per second.
Upon completion of the test, the test voltage shall be gradually reduced to
avoid voltage surges. The changing current shall be 50 mA maximum. During
the dielectric withstanding voltage test, the fault indicator shall be
monitored for evidence of disruptive discharge and leakage current. The
sensitivity of the breakdown test equipment shall be sufficient to indicate
breakdown when at least 0.5 mA of leakage current flows through the filter
under test. The test shall be performed with the components mounted in the
filter/ESA assembly enclosure. Filters for ac circuits shall be tested
with an ac source while filters for dc circuits shall be tested with a dc
source. After the test the filter shall be examined and measurements shall
be performed to include insulation resistance measurements to determine the
effect of the dielectric withstanding voltage test on specific operating
characteristics.
2.6.5.8
This is a test to measure the resistance offered by the insulating members
of a filter to an impressed direct voltage tending to produce a leakage
current through or on the surface of these filters. Insulation-resistance
measurements shall be made on an apparatus suitable for the characteristics
of the filter to be measured such as a megohm bridge, megohm-meter,
insulation-resistance test set, or other suitable apparatus. The test
shall be performed with the components mounted in the filter/ESA assembly
enclosure or mounted on a metal plate by the same holding method that will
be used for mounting in the enclosure. The bleeder resistor shall be
disconnected. The direct potential applied to the specimen shall be the
largest test condition voltage (100, 500, or 1,000 volts +10%) that does
not exceed the rated peak ac voltage or the rated dc voltage. A separate
dc power supply may be used to charge the filters to the test voltage. The
measurement error at the insulation-resistance value required shall not
exceed 10 percent. Proper guarding techniques shall be used to prevent
erroneous readings due to leakage along undesired paths.
Insulation-resistance measurements shall be made between the mutually
insulated points or between insulated points and ground. The insulation
resistance value shall be read with a megohmmeter and recorded after the
reading has stabilized. When more than one measurement is specified,
subsequent measurements of insulation resistance shall be made using the
same polarity as the initial measurements.
2.6.5.9
Current Sharing
Testing shall be performed with the filters mounted in the filter/ESA
assembly enclosure or mounted on a metal plate by the same holding method
that will be used for mounting in the enclosure. The filter inner
compartment terminals shall be loaded with a resistor equal in value to the
rated operating voltage divided by the sum of the current ratings of the
devices in parallel. The resistor shall be capable of dissipating the
total current. Rated operating voltage shall be applied at the filter
outer compartment terminals. The current into each filter outer
compartment terminal shall be monitored.
2.6.5.10
Harmonic Distortion Test
Harmonic distortion measurements shall be made using a spectrum analyzer
having a dynamic range of [70 dB] [_____] and a frequency range from [10
kHz to 1.7 GHz] [_____]. Total harmonic distortion shall be measured at
the input and output terminals of the filter when operating at 25, 50, and
SECTION 13095A
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