Pacific Power Source UPC-32, Руководство по эксплуатации

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SECTION 8 CALIBRATION
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SECTION 8
CALIBRATION
8 CALIBRATION
This section describes two methods of calibration of a UPC. To fully calibrate the SYSTEM for output
voltage, current limit and metering accuracy, it is necessary to perform both the MANUAL CALIBRATION
and then the EXTERNALLY REFERENCED CALIBRATION.
The first method ( 8.2 ) is a manual procedure requiring that the top cover of chassis be removed and
adjustments made. Manual calibration achieves calibration of the oscillator output gains (Output voltage),
the Programmable Current Limit circuit, and basic metering calibration. If output voltage accuracy to the
programmed value is desired, this procedure is necessary if EXTERNALLY REFERENCED CALIBRATION
is not performed (below) and CSC is not used.
The second method (8.3 ) is the EXTERNALLY REFERENCED CALIBRATION. It requires NO manual
adjustment or access of internal circuits (except for optionally calibrating the Current Limit circuit).
EXTERNALLY REFERENCED CALIBRATION achieves high calibration accuracy of the metering circuits.
This procedure must be performed in order for the CSC (Continuous Self Calibration) function to operate
accurately. The Manual calibration procedure is not necessary for CSC to operate accurately if
EXTERNALLY REFERENCED CALIBRATION is performed, as accurate metering assures that the CSC
function will track the programmed value.
8.1 CALIBRATION INTERVAL
Accurate control and measurement requires calibration every six months or after any service.
8.1.1 TEST EQUIPMENT REQUIREMENTS
The test equipment listed below is required for calibration of the UPC installed in a Power Source.
1. Digital Voltmeter: 4½ Digit True-RMS responding, 5000 Hz bandwidth, min.
2. Frequency counter: 5 digit counter, min.
3. Oscilloscope: (Optional)
4. *High current load (capable of 60% Peak rated output current of power source)
5. *Ammeter probe (Shunt type preferred) or ammeter capable of reading RMS amps.
* = (only needed for calibrating Programmable current limit)
8.2 MANUAL CALIBRATION PROCEDURE
The following calibration procedure verifies that system gains are set properly. ( 8.2.1 ) and ( 8.2.2 ) detail the
procedure used to check and adjust the various parameters. The procedure is written for three phase
systems. When calibrating single phase systems, ignore instructions relating to phases B and C.