Cc Ripple And Noise (Normal Mode) - Rigol DP831A Performance Verification Manual

Chapter 3 Constant Current Tests

CC Ripple and Noise (Normal Mode)

When the power supply is working in CC mode, the ripple and noise are usually
expressed in RMS value form.
DP831A is taken as an example to test the CC ripple and noise of DP800 series in the
following section.
Note: During the actual test, please select the corresponding test record form
according to the model of the DP800 power supply under test to set the
corresponding parameters, record and calculate the corresponding specifications.
Specification:
Ripple and Noise (20 Hz to 20 MHz)
Normal Mode Current
Test Procedures:
1. Turn off DP800. Connect DP800, AC power supply, resistive load and RMS
voltmeter according to Figure 2-1. Both the resistive load and RMS voltmeter are
connected with the channel output terminals of DP800; please refer to "Test
Precautions" for the connection method. Here, CH1 is taken as an example
and the connection method is also applicable to CH2 and CH3.
Note:
Do not connect the negative terminal of the output terminal of the channel

to be tested to the shielding ground; otherwise, a ground loop would be
formed. In Figure 2-3, the connection in figure A forms a ground loop while
figure B shows the correct connection.
Please ensure to test the CC ripple and noise of DP800 under full load

condition. Refer to Table 3-11 for the resistance of the resistive load.
2. Turn on the AC power supply; set its voltage to 230V and frequency to 50Hz.
Note:
The voltage setting of the AC power supply in this step should be in
accordance with the value selected by the voltage selector at the rear panel of
DP800.
3. Turn on DP800 and press the channel selecting key at the front panel to select
CH1 as the channel to be tested. Set the voltage and current of the channel
under test according to Table 3-11. Then, press the On/Off key corresponding
to the channel under test to enable the output of the channel.
4. Turn on the RMS voltmeter and select the AC voltage random measurement
mode (SETACV RNDM). Make sure that the power supply is in CC mode. Read
DP800 Performance Verification Manual
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RIGOL
3-11