AMETEK XHR 1000 Watt Series - Manual (Page 82)

Calibration
Calibrating for Readback Accuracy
82 Operating Manual for XHR Series Power Supply
Output
Current
Monitor
Circuit
Calibration
1. Ensure that the power supply is turned OFF. Disconnect any load.
2. Connect the shunt and DVM across the power supply output to read the output
current.
3. Connect a second DVM to the rear panel J2 terminals 10 (output current
monitor) and 6 (program/monitor signal return). See notes below.
4. Turn the current control fully counter-clockwise, then turn ON the power supply.
5. Set the supply output current to 1% of its model-rated output. See note below.
6. Adjust the output current monitor offset potentiometer (R81) until the monitor
DVM indicates 1% of the readback scale. (50 mVdc for 0-5 V readback or
100 mVdc for 0-10 Vdc readback.)
7. Set the supply output current to the model-rated maximum output.
8. Adjust the output current monitor range potentiometer (R100) until the monitor
DVM reads 100% of the readback scale. (5 Vdc for 0-5 V readback or 10 Vdc
for 0-10 Vdc readback.)
Repeat this adjustment until the monitor scale is within the product specifications as
found in Section 1, or to the accuracy that your application requires.
Notes:
• The recommended accuracy of the DVM and DC shunt-DVM combination is
four times better than your desired readback accuracy. The recommended
current ratings for the DC shunt and connecting wire is at least 10% greater than
the power supply's output current rating.
• Depending on the readback accuracy required in your application, you may use
the front panel ammeter in place of the DC shunt-DVM combination.
• Calculate the required output current reading using I = V/R where I is the
current, V is the DVM reading, and R is the DC shunt resistance.