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range. In the event of a measurement failure, the PMC DEBUG UTILITIES (see Sec. 2.8.4.1) can
be used to display measurement values and provide additional operational data for localizing a
fault or for aid in setting manual adjustments.
The following tests are performed to assess the PMC voltage measurement and output functions.
2.8.3.8.1 Voltage Measurement Offset Test
The output of the voltage measurement amplifier is tested with a zero-signal input. The amplifier
output must be less than a prescribed value or a FAIL message is displayed.
2.8.3.8.2 DC Voltage Measurement Gain Test
The PMC precision reference is measured using the DC voltage measurement system. The
resulting measurement amplifier DC gain value is compared with the expected value and a FAIL
message is displayed if the difference falls outside a prescribed error limit.
2.8.3.8.3 AC Voltage Measurement Gain Test
The PMC precision reference is measured again using the AC voltage measurement system. The
resulting measurement AC amplifier gain value is compared with the expected value and a FAIL
message is displayed if the difference falls outside a prescribed error limit.
2.8.3.8.4 Voltage Overload Test
The voltage overload test is performed in two steps. First the overload input is tested with zero
voltage applied to its input. The measured overload value should be less than a prescribed limit;
otherwise a FAIL message is displayed. In the second step a test voltage is applied to the overload
input and the overload measurement is repeated. The overload value should exceed a prescribed
value for passage of the test.
2.8.3.8.5 Voltage Output Range Test
Each of the 5 voltage output ranges are tested for correct output at full-scale values. The tests are
performed with DC output set to the lowest voltage range, range 1, at 100 mV, then range 2 at 1
V, range 3 at 10 V, range 4 at 100 V and range 5 at 1000 V. This test also checks the voltage
power converter, which supplies the high voltage output amplifier.
The range test voltage outputs are measured and compared with an expected value. If the test
output value deviates from the expected value by more than a prescribed limit then a test failure
for the range is displayed and corrective maintenance is required.
2.8.3.9 VOLTAGE SOURCE TEST
Voltage waveform generation and control circuitry is tested in this series of tests. The operation
of the digital to analog sinewave generator and the attenuator control circuits are exercised.
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