Agilent Technologies 6012B Service Manual page 19

g. When the reading settles, record the output voltage again. Check that the two recorded readings differ no more than:
± 0.011Vdc (6010A)
± 0.0037Vdc (6011A)
± 0.007Vdc (6012B)
± 0.033Vdc (6015A)
Source Effect (Line Regulation). Source effect is the change in dc output voltage resulting from a change in ac input
voltage from the minimum to the maximum value as specified in Input Power Requirements 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 maximum.
b. Connect the unit to the ac power line through a variable autotransformer which is set for low line voltage (104Vac for
120Vac).
c. Turn the unit's power-on, and turn up current setting to full output.
d. Turn up output voltage to:
60.0Vdc (6010A)
20.0Vdc (6011A)
20.0Vdc (6012B)
500Vdc (6015A)
as read on the digital voltmeter.
e. Reduce the resistance of the load to draw an output current of:
17.0Adc (6010A)
50Adc (6011A)
50Adc (6012B)
2.0Adc (6015A)
Check that the unit's CV LED remains lighted.
f. Record the output voltage at the digital voltmeter.
g. Adjust autotransformer to the maximum for your line voltage.
h. When the reading settles record the output voltage again. Check that the two recorded readings differ no more than:
± 0.011Vdc (6010A)
± 0.004Vdc (6011A)
± 0.005Vdc (6012B)
± 0.063Vdc (6015A)
PARD (Ripple And Noise). Periodic and random deviations (PARD) in the unit's output-ripple and noise-combine to
produce a residual ac voltage superimposed on the dc output voltage. Constant-voltage PARD is specified as the
root-mean-square (rms) or peak-to-peak (pp) output voltage in a frequency range of 20Hz to 20MHz (10MHz, 6010A).
RMS Measurement Procedure. Figure 2-4 shows the interconnections of equipment to measure PARD in Vrms. To
ensure that there is no voltage difference between the voltmeter's case and the unit's case, connect both to the same ac
power outlet or check that the two ac power outlets used have the same earth-ground connection.
Use the common-mode choke as shown to reduce ground-loop currents from interfering with measurement. Reduce noise
pickup on the test leads by using 50Ω coaxial cable, and wind it five turns through the magnetic core to form the
common-mode choke. Proceed as follows:
a. Connect the test equipment as shown in Figure 2-4. Operate the load in constant resistance mode (Amps/Volt) and set
resistance to maximum.
b. Turn the unit's power-on, and turn up current setting to full output.
c. Turn up output voltage to:
60Vdc (6010A)
7Vdc (6011A)
60Vdc (6012B)
200Vdc (6015A)
19