Chapter 3 Calibration Procedures
Constant Voltage (CV) Verifications
49
3
CV Load Regulation
This test measures the change in the output voltage resulting from a change in
the output current from full to no load.
1Turn off the power supply and connect a digital voltmeter between the (+) and
(-) terminals of the output to be tested as shown in Figure 3-1.
2Turn on the power supply and select the desired output to be tested using the
meter and adjust selection key on the front panel. Enable the outputs and set
the display to the limit mode. When the display is in the limit mode, program
the current of the selected output to the maximum programmable value and
the voltage to the full-scale value (see Table 3-2).
3Operate the electronic load in constant current mode and set its current to the
full scale value of the output to be tested (see Table 3-2). Check that the front
panel CV annunciator remains lit. If not lit, adjust the load so that the output
current drops slightly until the CV annunciator lights. Record the output
voltage reading on the digital voltmeter.
4Operate the electronic load in open mode (input off). Record the output voltage
reading on the digital voltmeter again. The difference between the digital
voltmeter readings in steps (3) and (4) is the CV load regulation. The difference
of the readings should be within the limit specified below for each output
tested.
5Repeat steps (1) through (4) for the remaining outputs.
Output Programming Accuracy
+6V 2.6 mV
+25V 4.5 mV
-25V 4.5 mV