Specifications
Performance Verification
Step 6. The output voltage should return to within the specified voltage at the specified time following the load
change. Check the loading transient by triggering on the negative slope. Record the voltage at time “t” in the per-
formance test record form under “Transient Response”.
Current Programming and Readback Accuracy
This test verifies that the current programming and measurement functions are within specifications.
Step 1. Turn off the power supply and connect an electronic load and a precision current shunt to the output ter-
minals. The current shunt should be able to measure the power supply's rated current. Connect a DMM directly across
the current shunt (see Test Setup B).
Step 2. Turn on the power supply and program the instrument settings as described in the test record form under “Cur-
rent Programming & Readback, Min Current”. Turn the output on.
Step 3. Turn on the electronic load and set it to CV mode. Program it to the voltage setting described in the test record
under “Current Programming & Readback, Min Current”. The power supply's output status should be “CC”, and the out-
put voltage should be close to the electronic load's voltage setting.
Step 4. Divide the voltage drop (DMM reading) across the current shunt by the shunt resistance to convert to amps
and record this value. Also, record the current measured over the interface. The readings should be within the limits
specified in the test record form for the appropriate model under “Current Programming & Readback, Minimum Cur-
rent”.
Step 5. Program the instrument settings as described in the test record form under “Current Programming & Read-
back, High Current”.
Step 6.Divide the voltage drop (DMM reading) across the current shunt by the shunt resistance to convert to amps
and record this value. Also, record the current reading measured over the interface. The readings should be within the
limits specified in the test record form for the appropriate model under “Current Programming & Readback, High Cur-
rent”.
Constant Current Load Effect
For the 1000 V and 1500 V models, the CC load effect tests are performed up to 750 VDC, as this is
the maximum input rating of the recommended electronic loads.
This test measures the change in output current following a large change in output voltage.
Step 1. Keep the connections as in Current Programming and Readback Accuracy (see Test Setup B).
Step 2. Turn on the power supply and program the instrument settings as described in the test record under “CC Load
Effect”.
Step 3. Set the electronic load to the first voltage value as described in the test record form under “CC Load Effect”.
The power supply's output status should be “CC”.
Step 4. Divide the voltage drop (DMM reading) across the current shunt by the shunt resistance to convert to amps
and record this value.
Step 5. Set the electronic load to the second voltage value as described in the test record form under “CC Load Effect”..
Divide the voltage drop (DMM reading) across the current shunt by the shunt resistance to convert to amps and record
this value. The difference in the current readings in steps 4 and 5 is the load effect, which should not exceed the value
listed in the test record for the appropriate model under “CC Load Effect”.
126 Agilent N8900 Series Operating and Service Guide