Xantrex Technology RS232-XPD - Manual (Page 56)

Calibration
Current Mode Calibration
54 Operating Manual for RS-232 for XPD Series Power Supply
Current Mode Calibration
Current
Calibration
Setup
1. Disconnect the load from the power supply to be calibrated.
2. Connect a shunt across the supply's output terminals.
3. Connect a voltmeter across the shunt.
Figure 4.2 Current Calibration Setup
Current
Program
Calibration
Procedure
1. Connect the shunt and voltmeter to the power supply as shown in Figure 4.2.
2. Activate calibration mode by sending command CMODE ON or CMODE 1 to
the power supply.
3. Send command ILO; VLO to the power supply. Measure and record the output
shown on the external voltmeter.
4. Send command IHI; VHI to the supply Measure and record the output voltage
shown on the external voltmeter.
5. Calculate ILO and IHI from the voltages read from the external voltmeter and
the shunt resistance. I=V/R.
6. Send the command IDATA , to the power supply. and are
the current values obtained from sending the ILO and IHI commands to the
power supply. When the power supply is calibrated, the low to high current
program calibration values are stored as constants.
7. Program the supply at various levels using the ISET command to confirm that
the calibration was successful and that linearity is observed. Refer to the current
program accuracy specification in Section 1.
8. Turn off calibration mode by sending the command CMODE OFF or CMODE 0
to the power supply.
V
- +
VOLTMETER
Power Supply
Negative Output
Power Supply
Positive Output
Current Sensing
Resistor