I just bought a back up ups xs1000 and the building wiring fault light is on. Is this a problem
Yes this is a problem, but it indicates a problem with either the outlet that the UPS is plugged into (make sure you are using a direct wall outlet and not a daisy chained connection) or the circuit that powers it.
The reasons for a site wiring fault are as follows:
1) Overloaded Neutral - this means there is excess voltage on the neutral (return wire) on the outlet the unit is using. This can be caused by inefficient or old electrical devices that are plugged into a connected outlet or on the same circuit as the UPS. It can also be caused by bad neutral line wiring.
2) Reversed Polarity - The hot and neutral lines are reversed.
3) Missing ground wire/ ground connection - either the ground on the outlet is damaged, or there is no actual ground reference available. This can also be caused if you use a 3 prong to 2 prong adapter or attempt to alter the plug on the UPS.
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