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Use of Smart-UPS and Back-UPS with GFI (GFCI) Receptacles or Breakers

Issue:
GFI (aka "GFCI") Receptacle or circuit breaker trips after UPS or Surge Arrest is connected.

Product Line:
Smart-UPS, Back-UPS, and Surge; All Product Families

Environment:
UPS or Surge Protector plugged in to GFI receptacle or a standard receptacle which is protected by a GFI breaker.

Cause:
A ground fault interrupter (GFI) is a safety device required by the National Electrical Code, primarily in damp or wet applications.
It's purpose is to avert personal injury.

UPS systems and computer equipment exhibit leakage currents. These currents are a natural result of the common mode filters present in computers and UPS's.

The common mode filtering in Smart-UPS, Back-UPS, and Surge Arrest products may produce small amounts of excess current on their input as part of their normal operation.

This is referred to as "leakage current".

In addition, every piece of load connected creates a certain amount of leakage current which it also passes along through the UPS.

The leakage current of the UPS and all of the load attached is cumulative and may cause nuisance tripping of a GFCI receptacle or Breaker.
This may occur whether the output of the UPS is switched "on" or "off"
This behavior may be experienced when using GFI products manufactured by Schneider Electric or any other vendor. 

Resolution:
The most common culprit is the load attached to the UPS/Surge product. Try attaching different load and see if that improves performance. 
You can try to replace the GFCI device and see if this solves the problem. Sometimes as GFI devices age they will drift out of tolerance. You may also find that some GFI devices are more sensitive than others. Breaker style GFI protection is typically more tolerant than receptacle based.

If the circuit is not required to be GFI by code, you may consider changing to a non-GFI receptacle or breaker.
Typically GFI protection is only required by code in wet/damp locations such as Kitchens, Baths, or exterior receptacles, but your local electrical code may vary. 

APC products should only be used in compliance with all local and national electric codes. 
APC does not manufacture any UPS or Surge devices designed for use in wet/damp applications.     

There are thousands of successful installations of UPS and computer equipment with GFI's, however every application and load is different.
For best performance, use your UPS or Surge Protector with a standard non-GFI power source.  

 
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