March 2017 (1)

Some time ago while presenting a grounding and protection symposium and explaining the differences between an uninterruptible power supply (UPS) system and a surge protector, an engineer in the back of the room yelled, ”A UPS is not a surge suppressor.”  While I gladly accept help from the audience and generally agree with his statement, some types of UPS systems provide isolation from harsh AC or grounding. However, how effective are they really?