Chapter 3 Calibration Procedures

Constant Current (CC) Verifications

CC Load Regulation

This test measures the change in output current resulting from a change in the load from full-scale output voltage to short circuit.

1Turn off the power supply and connect the output to tested as shown in Figure 3-1with the digital voltmeter connected across the 0.19 current monitoring resistor (RM).

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 voltage to the maximum programmable value and the current to the full- scale value (see Table 3-2).

3Operate the electronic load in constant voltage mode and set its voltage to the full scale value of the output to be tested (see Table 3-2). Check that the CC annunciator is on. If it is not, adjust the load so that the output voltage drops slightly. Record the current reading by dividing the voltage reading on the digital voltmeter by the resistance of the current monitoring resistor.

4Operate the electronic load in short (input short) mode. Record the current reading again by dividing the voltage reading on the digital voltmeter by the resistance of the current monitoring resistor. The difference between the current readings in step (3) and (4) is the load regulation current. The difference of the readings should be within the limit specified below for each output tested.

Output

Difference

 

 

+6V

0.75 mA

 

 

+25V

0.35 mA

 

 

-25V

0.35 mA

 

 

5Repeat steps (1) through (4) for the remaining outputs.

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Agilent Technologies E3631A manual CC Load Regulation