Appendix Service Information
Constant Voltage (CV) Verifications
169
Service
Information
Constant Voltage (CV) Verifications
Constant Voltage Test Setup
If more than one meter or if a meter and an oscilloscope are used, connect
each to the (+) and (-) terminals by a separate pair of leads to avoid mutual
coupling effects. Use coaxial cable or shielded 2-wire cable to avoid noise
pick-up on the test leads.
Table A-3 Verification Programming Values
Voltage Programming and Readback Accuracy
This test verifies that the voltage programming and GPIB or RS-232 readback
functions are within specifications. Note that the readback values over the
remote interface should be identical to those displayed on the front panel.
You should program the power supply over the remote interface for this test
to avoid round off errors.
1Turn off the power supply and connect a digital voltmeter between the (+) and
(-) terminals of the output to be tested as shown in Figure A-1.
2Turn on the power supply. Select the high voltage range (20V/1.5A)† and enable
the output by sending the commands:
VOLT:RANG P20V (E3640A model)
OUTP ON
3Program the output voltage to 0 volt and current to full scale rated value
(1.5 A)† by sending the commands:
VOLT 0
CURR 1.5 (E3640A model)
4Record the output voltage reading on the digital voltmeter (DVM). The reading
should be within the limit of (0 V ± 10 mV). Also, note that the CV, Adrs, Limit,
and Rmt annunciators are on.
Model Low voltage
range
High voltage
range Model Low voltage
range
High voltage
range
E3640A 8V/3A 20V/1.5A E3643A 35V/1.4A 60V/0.8A
E3641A 35V/0.8A 60V/0.5A E3644A 8V/8A 20V/4A
E3642A 8V/5A 20V/2.5A E3645A 35V/2.2A 60V/1.3A
†For E3640A model, and see Table A-3 for other models