Chapter 3 Calibration Procedures
Constant Current (CC) Verifications
54
Constant Current (CC) Verifications

Constant Current Test Setup

Follow the general setup instructions in the "Measurement Techniques" section
starting on page 45 and the specific instructions will be given in the following
paragraphs.

Current Programming and Readback Accuracy

This test verifies that the current programming and GPIB or RS-232 readback
functions are within specifications. Note that the readback values over the
remote interface should be identical to those displayed on the front panel. The
accuracy of the current monitoring resistor must be 0.1% or better.
You should program the power supply over the remote interface for this test
to avoid round off errors.
1Turn off the power su pply and connect a 0.19 current monitoring resistor (RM)
across the output to be tested and a digital voltmeter across the current
monitoring resistor (RM).
2Turn on the power supply. Enable the outputs and select the desired output to
be tested by sending the commands:
OUTP ON
INST {P6V|P25V|N25V}
3Program the selected output voltage to 5.0 volts and the current to 0 amps by
sending the commands:
VOLT 5
CURR 0
4Divide the voltage drop (DVM reading) across the current monitoring resistor
(RM) by its resistance to convert to amps and record this value (IO). This value
should be within the limits specified below for each output tested. Also, note
that the CC, Adrs, Lmt, and Rmt annunciators are on.
Output Programming Accuracy
+6V 0 A ± 10 mA
+25V 0 A ± 4 mA
-25V 0 A ± 4 mA