Chapter 3 Calibration Procedures
Constant Current (CC) Verifications
57
3
6 Record the value displayed on the controller. This value should be within the 
limit of (I
O
 ± 5 mA).
7 Program the output current to the full rated value (20.0 A)* or (7.0 A)** by 
sending the command:
CURR 20.0 (E3633A)
CURR 7.0  (E3634A)
8 Divide the voltage drop (DVM reading) across the current monitoring resistor 
(R
M
) by its resistance to convert to amps and record this value (I
O
). This value 
should be within the limit of (20 A ± 50 mA)* or (7A ± 24 mA)**.
9 Readback the output current over the remote interface by sending the 
command:
MEAS:CURR?
10 Record the value displayed on the controller. This value should be within the 
limit of (I
O
 ± 35 mA)* or (I
O
 ± 15.5 mA)**.
CC Load Effect (Load Regulation)
This test measures the change in output current resulting from a change in the 
load from full rated output voltage to short circuit.
1 Turn off the power supply and connect the output to tested as shown in 
Figure 3-1 with the digital voltmeter connected across the 0.01 
 current 
monitoring resistor (R
M
).
2 Turn on the power supply. Select the 8V/20A* or 25V/7A** range, enable the 
output, and set the display to the limit mode. When the display is in the limit 
mode, program the output voltage to the full rated value (8.0 V)* or (25.0 V)** 
and the output current to the full rated value (20.0 A)* or (7.0 A)**.
3 Set the voltage of the electronic load to (6.0 V)* or (23.0 V)** to operate it in 
constant voltage mode since a voltage drop occurs on the load wires when 
(20.0 A)* or (7.0 A)** flows on the load wires. Check that the 
CC annunciator 
is o n. If it is n ot, ad j u s t  th e  l o ad  s o  t h a t th e  ou tp u t  v o lta ge d rops sligh tly. Rec ord 
the current reading by dividing the voltage reading on the digital voltmeter by 
the resistance of the current monitoring resistor.
4 Operate 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 of (2.25 mA)* or 
(0.95 mA)**.
*For Agilent E3633A Model     **For Agilent E3634A Model