HP 6038A, Service Manual

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Note:
A current-monitoring resistor with 1% accuracy is suitable for all tests except current programming
accuracy and current readback accuracy. For these tests, use the shunt listed in Table 2-1.
Figure 2-4. Current-Monitoring Resistor Setup
HP-IB Controller. Most performance tests can be performed using only front-panel controls. However, an HP-IB
controller is required to perform the voltage and current programming accuracy tests and the voltage and current readback
accuracy tests.
Constant Voltage (CV) Tests
CV Setup. If more than one meter or a meter and an oscilloscope are used, connect each to the + S and - S terminals by a
separate pair of leads to avoid mutual coupling effects. Connect only to + S and -S because the unit regulates the output
voltage b S and - S, not b OUT and -OUT. Use coaxial cable or shielded 2-wire cable to avoid pickup on
test leads. For all CV tests set the output current at full output to assure CV operation.
Voltage Programming And Readback Accuracy. This procedure verifies that the voltage programming and readback
functions are within specifications. An HP-IB controller must be used for this test.
a.
Connect digital voltmeter b S and - S.
b. Turn on ac power to the power supply.
c. Send string:
’’VSET 0.1; ISET 30’’ (6033A).
’’VSET 0.09; ISET 10" (6038A).
d. The DVM reading should be in the range:
0.090 to 0.109Vdc (6033A).
0.050 to 0.130Vdc (6038A).
Note the reading.
e. Enter and run the following program:
10 OUTPUT 705; "VOUT?"
20 ENTER 705;A
30 DISP A
40 GOTO 10
50 END
f. The value displayed by the controller should be the value noted in step d:
±
0.006Vdc (6033A).
±
0.015Vdc (6038A).
g. Send string:
"VSET 20; ISET 30" (6033A).
’’VSET 60; ISET 10" (6038A).
h. The DVM reading should be in the range:
19.984 to 20.016Vdc (6033A).
59.939 to 60.061Vdc (6038A).
Note the reading.