RIGOL 
  
  Service Guide for DM3000 Series 
 
1.  Zero Offset Test 
When testing Zero Offset, firstly apply a 4-wire short across the Input HI-Lo and 
Sense HI-Lo terminals (front terminals), then leave the current terminal open as 
shown in figure 3-1: 
 
Figure 3-1   
The Input HI-LO and Sense/Ref HI-LO Terminals in Short Circuit 
 
Next, perform the test items in table 3-2 or table 3-3 one by one, then compare 
the test results with the error range in the tables.