Chapter 3 Constant Current Tests    RIGOL 
DP800 Performance Verification Manual   
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  <2mArms 
 
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