reason for doing electronic earthing in UPS? reason?

Question

for connecting lighting load it is necessary for provide seperate earthig for ups alone?reason

Answer 1

When the AC mains are powering the load through the UPS, they provide the earth return, providing it is wired correctly according to national electric (or other appropriate) code.

BUT, when the battery is connected as the power source, it "floats" with respect to earth, so you need a separate connection to earth for electrical safety.

If the AC mains are cut off, it may be because of a completely severed line -- including the earth return. This is a likely scenario.

For pure lighting loads it is not as critical as for other loads that would require human touch, but it's probably NEC (code). If there is even a single duplex outlet on the lighting chain, that's reason enough to provide the earth ground path.


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