This video explores potential causes of ground faults in elevator controls after EGC addition. Get practical steps to diagnose and resolve the problem. Proper earthing is vital for protecting users from electric. However, in actual applications, distribution boxes often encounter a series of problems, which not only affect the normal operation of the power system, but also may bring safety hazards. Your boss might insist on it, while your. Power from factory ground must be installed by a qualified electrician. Each DISTRIBUTION BOX and controller must be grounded.