Verification ProcedureVoltage Programming and Readback AccuracyThis test verifies that the voltage programming and measurement functions are within specifications.Step 1. Turn off the unit under test. Only connect the DMM to the sense screws (see Test Setup A). DoNOT connect the RP79xxA load unit.Step 2. Turn on the unit under test and program the instrument settings as described in the test recordform under “Voltage Programming & Readback, Min Voltage”. Turn the output on. The output statusshould be “CV”, with the output current close to zero.Step 3. Record the output voltage reading from the DMM (Vout) and the voltage measured by theinstrument over the interface. The readings should be within the limits specified in the test record formfor the appropriate model under “Voltage Programming & Readback, Minimum Voltage”.The next step applies the full output voltage of the unit under test to the output.Step 4. Program the instrument settings as described in the test record form under “VoltageProgramming & Readback, High Voltage”.Step 5. Record the output voltage reading from the DMM (Vout) and the voltage measured by theinstrument over the interface. The readings should be within the limits specified in the test record formfor the appropriate model under “Voltage Programming & Readback, High Voltage”.Constant Voltage Load EffectThis test measures the change in voltage resulting from a change in current from full load to no load.Step 1. Turn off the unit under test. Connect the DMM to the sense screws and connect the RP79xxAload unit. Make sure that the voltage rating of the RP79xxA load matches the voltage rating of the unitunder test. (see Test Setup A).Step 2. Turn on the unit under test and program the instrument settings as described in the test recordform under “CV Load Effect”. Turn the output on.Step 3. Set the RP79xxA load for the output current as described in the test record form under “CVLoad Effect”. Turn the output on. The output status of the unit under test should be “CV”. If it isn’t,adjust the load so that the output current drops slightly.Step 4. Record the output voltage reading from the DMM.Step 5. Turn off the output of the RP79xxA load. Record the voltage reading from the DMM again. Thedifference between the DMM readings in steps 4 and 5 is the load effect, which should not exceed thevalue listed in the test record form for the appropriate model under “CV Load Effect”.Keysight RP7900 Series Operating and Service Guide 2696 Verification and Calibration
