Appendix Service Information
Constant Voltage (CV) Verifications
183
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.
1 Turn 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.
2 Turn on the power supply. Select the output to be tested and the high voltage range
(20V/1.5A)
†
and then enable the output by sending the commands:
INST:SEL {OUT1|OUT2}
VOLT:RANG P20V
(E3646A model)
OUTP ON
3 Program 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
(E3646A model)
4 Record the output voltage reading on the digital voltmeter (DVM). The reading should
be within the limit of (0 V ± 10 mV) for output1 or (0 V ± 25 mV) for output2. 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
E3646A 8V/3A 20V/1.5A E3647A 35V/0.8A 60V/0.5A
E3648A 8V/5A 20V/2.5A E3649A 35V/1.4A 60V/0.8A
†
For E3646A model, and see Table A-3 for other models.