KEPCO BHK 1000-0.2MG, Operator'S Manual

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BHK-MG (OPR) (OPR) 032816
4-9
10.The text window reads
CURR ZERO Adjust
. Using the fine adjust < and > buttons (see
PAR. 4.4.3), adjust output until DVM is as close to 0 as possible but slightly positive, then
click
OK button.
11. The text window reads
CURR F.S.Adjust
. Using the coarse << and >> and fine < and >
buttons (see PAR. 4.4.3), adjust output current until the DVM voltage reading corresponds as
closely as possible, but above, the rated maximum current. Use
I
= E/R where E is the DVM
reading (Volts), R is measured value of the precision shunt resistor (Ohms) used to indirectly
measure
I
, the rated BHK-MG current in Amperes. Click the OK button when complete.
12.The Current Magnifier window opens (see Figure 4-6). The unit automatically sets output
current to less than 1/10th the rated nominal current (approximately 8% of nominal current
range). The DVM measures the voltage across the shunt. Indirectly measure the output cur-
rent in Amperes using
I
= E/R where E is the DVM reading (Volts) and R is measured value
of the precision shunt resistor (Ohms). Enter the indirectly measured current value (in milli-
Amperes) in the field provided and click
OK .
NOTE: The range of useful values for calibrating current magnification has a tolerance of
±10%. For example, if the measured value entered for the BHK 1000-0.2MG is
between 22 and 18 mA, current magnification will be calibrated. If the value is outside
this range the unit uses the default value of 20 mA and current magnification is not cal-
ibrated. Note that this calibration only improves the accuracy of the output current
readback value, and does not affect the setting value.
FIGURE 4-6. CURRENT MAGNIFIER WINDOW
13.The text window reads
Cal Current LO Range? no=skip.
Click YES button to perform
low range current calibration.
14.The text window reads
Connect shunt across output
. If the shunt is not already con-
nected, connect precision shunt resistor (see PAR. 4.2) OUT and –OUT terminals.
After connecting the shunt click
OK button.
15.The text window reads
With shunt connected across output, connect DVM
across shunt
. Connect 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.
16.The text window reads
CURR ZERO Adjust
. Using the fine adjust < and > buttons (see
PAR. 4.4.3), adjust output until DVM is as close to 0 as possible but slightly positive, then
click
OK button.