Argantix KDC 100-100, User Manual

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User Manual
KDC Series II DC Power Supplies 89
7.6 Non-Routine Calibration
The following calibrations are not required on a routine basis:
7.6.1 VOLT NOM Adjustment
Since the KDC controller is used for all output voltage range models, the internal reference
signals are normalized for each model using calibration DAC's. This normalization is generally
done at the factory and does not have to be repeated unless a power module has been replaced
in the field.
This normalized voltage reference signal is available at TP21 and also at the Auxiliary I/O DB9
connector (J21) if the -IF option is installed. See Table 3-6 for pin-out. If the -IF option is not
installed, the top cover has to be removed to access TP21 on the back of the controller board
behind the front panel. The normalized output voltage at these test points is 10.00 volts for full
scale output voltage, regardless of the model.
The first step in the adjustment of the normalized output is to establish a known voltage output
condition. The first normalized output that should be adjusted is the voltage.
1. Program an output voltage that gives an actual output of ½ scale voltage as verified by an
external DVM.
2. Attach a DC voltmeter to TP21. Use TP1 for the DC voltmeter common.
3. Adjust the Vnom DAC for a voltage at TP21 indicated by the following formula: The Vnom
DAC adjustment is available from the front panel Calibration menu. Select Output Cal, Vnom.
Use the formula below to determine correct TP21 test point measured voltage:
V (TP21) = 10 x (Actual Output Voltage)/ (Full Scale Voltage Range)
Note: The Actual Output Voltage will change while adjusting the VOLT NOM
DAC. If there was any change made to this adjustment, the output voltage
and voltage measurement must be re-calibrated. Refer to paragraph 7.4.1
and 7.5.1 respectively.