KEPCO BHK-MG 40W (Half Rack) Series - Manual (Page 119)

BHK-MG 1/2 OPR 121313
4-7
tons (see PAR. 4.5.2), adjust the output until the DVM is a close as possible, but above, the
rated nominal voltage, e.g., 1000.00V for the BHK 1000-40MG, then click OK button.
7. Voltage calibration is complete and the indicator below the VOLTAGE button on the calibra-
tion panel (Figure 4-3) lights green. If desired, the voltage calibration can be repeated by
clicking VOLTAGE button at the calibration panel. If current calibration is not necessary, pro-
ceed to step 14.
8. At the calibration panel (Figure 4-3) click CURRENT button to begin current calibration of the
unit. The text window reads
Connect Shunt
and the message Measure and Adjust is dis-
played beneath the text window. The message Connect DVM to Calibration Resistor is
displayed above SAVE CALIBRATION button.
9. Connect precision shunt resistor (see PAR. 4.2) across +OUT and –OUT terminals and con-
nect DVM (high) to the shunt sensing terminal that correlates to +OUT and DVM (low) to the
shunt sensing terminal that correlates to –OUT. Click OK button to proceed to next step.
10.The text window reads
Curr Min Calibration
and the message Measure and Adjust is
displayed beneath the text window. Using the " and # buttons (see PAR. 4.5.2), adjust out-
put until DVM is as close to 0 as possible but slightly positive, then click OK button.
11. The text window reads
Curr Max Calibration
and the message Measure and Adjust is
displayed beneath the text window. Using the coarse ! – and – " and fine " and # but-
tons (see PAR. 4.5.2), adjust the output until the DVM voltage reading corresponds as
closely as possible, but above, the rated maximum current, e.g., 0.08 Amperes (80mA) for
the BHK 500-80MG. Use I = E/R where E is the DVM reading (Volts), R is measured value of
the precision shunt resistor (Ohms) used to calculate I, the rated BHK-MG current in
Amperes. Click the OK button.
12.The unit automatically changes output current to approximately 1/10th the rated nominal cur-
rent. The text window reads
Enter Current reading
. The DVM measures the voltage
across the shunt. Calculate the output current using I (in Amperes) = E/R where E is the
DVM reading (Volts), R is measured value of the precision shunt resistor (Ohms). Enter the
calculated current value (in Amperes) in the field provided and click OK.
13.If the value is accepted, current calibration is complete and the indicator below the CUR-
RENT button on the calibration panel (Figure 4-3) lights green. If desired, the current calibra-
tion can be repeated by clicking CURRENT button at the calibration panel. If the value is not
within the allowable range, the message window displays either Entered Value is too small
or Entered Value is too large. For example, the value entered for the BHK 500-80MG
should be around 0.008. Only values between 0.0088 and 0.0074 will be accepted. If the
value entered is too small or too large, repeat measurement and calculation of step 12, enter
the correct value and click OK.
14.Click on the CALIBRATION SAVE button on the calibration panel (Figure 4-3) to save the
calibration entries and exit calibration. To return to the old calibration and exit without saving
the calibration just performed, click on the Calibration Close button on the main panel.