25
17.5Adc (0.0175Vdc across Rm) (6012B) Check that the AMPS display reads about 17.5 amps.
2Adc (0.20Vdc across Rm) (6015A) Check that the AMPS display reads about 2 amps.
d. Increase the load resistance until the output voltage at +S and -S increases to:
200Vdc (6010A)
20Vdc (6011A)
60Vdc (6012B)
500Vdc (6035A)
Check that the CC LED is lighted and AMPS display still reads ≈ current setting.
e. Record voltage across Rm.
f. Short circuit the load.
g. When the reading settles (≈ 10s), record the voltage across Rm again. Check that the two recorded readings differ no
more than:
0.105mVdc (6010A)
± 0.010mVdc (6011A)
± 0.0118mVdc (6012B)
± 3.4mVdc (6015A)
h. Disconnect the short across the load.
Source Effect (Line Regulation). Constant current source effect is the change in dc output current resulting from a
change in ac input voltage from the minimum to the maximum values listed in the Specifications Table in the Operating
Manual. Proceed as follows:
a. Connect the test equipment as shown in Figure 2-3. Operate the load in constant resistance mode (Amps/Volt) and set
resistance to minimum.
b. Connect the unit to the ac power line through a variable autotransformer set for low line voltage (e.g. 104Vac for
120Vac).
c. Switch the unit's power-on and turn up output voltage setting to full output.
d. Turn up output current to:
17.0Adc (6010A)
120Adc (6011A)
50Adc (6012B)
5.0Adc (6015A)
Check that the AMPS display reads ≈ current setting.
e. Increase the load resistance until the output voltage between + S and - S increases to:
60Vdc (6010A)
7.0Vdc (6011A)
20.0Vdc (6012B)
200Vdc (6035A)
Check that the CC LED is still on and the AMPS display still reads ≈ current setting.
f. Record the voltage across Rm.
g. Adjust autotransformer to the maximum for your line voltage.
h. When the reading settles record the voltage across Rm again. Check that the two recorded readings differ no more than:
± 0.067mVdc (6010A)
± 0.018mVdc (6011A)
± 0.015mVdc (6011A)
± 18mVdc (6015A)
PARD Ripple And Noise. Periodic and random deviations (PARD) in the unit's output (ripple and noise) combine to
produce a residual ac current as well as an ac voltage super-imposed on the dc output. The ac voltage is measured as
constant-voltage PARD. Constant-current PARD is specified as the root-mean-square (rms) output current in a frequency
range 20Hz to 20MHz with the unit in CC operation. To avoid incorrect measurements, with the unit in CC operation,
caused by the impedance of the electronic load at noise frequencies, use a:
0.4Ω (6010A)
0.058Ω (6011A)
0.4Ω (6012B)
40Ω (6015A)