Abstract：This paper proposed an effective method for the maintenance through analysis of Varian high energy accelerator HVOC
interlock failure: section cut and dummy load service method combined with replacement method. There were two possible reasons
to cause Varian high energy accelerator HVOC interlock failure, one was charging circuit overcurrent in modulator cabinet, the other
was the mismatching of discharge circuit in load. This paper analyzed different failure reasons and proposed corresponding solutions.
In order to solve the problem quickly, when similar failures happens, maintenance person should judge failure cause and find failure
location on the basis of being familiar with circuit diagram and do targeted maintenance.
