7v ~ 12v returning onto mains power from BackUps-400va/600va

[alexapcbrazil_apc]

This was originally posted on APC forums on 1/26/2016

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I have an electrician doing some electrical work on my home, where I have 2 x BackUps 400va, 2 x BackUps 600va and a few other models installed. All of the BackUps 400va & 600va are returning between 7v to 12v onto the electrical wiring, which was noticed during some testing on the main electrical supply for the property. I tested this with a voltmeter, and on the power-cord for each of the units, there is a varying voltage showing of between 7v to 12v, fluctuating. 

Is this normal? The SmartUPS 1500va and BackUps 1500va Pro do not do this.

Many thanks for the feedback!

[BillP]

This reply was originally posted by Bill on APC forums on 1/27/2016

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Hi Alex,

What is the exact model numbers of the BackUps 400va, and BackUps 600va? You will find the information on a bar code sticker on the back or bottom of the units.

[alexapcbrazil_apc · Accepted solution]

This was originally posted on APC forums on 1/27/2016

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Hi Bill,

I am away from the property until the weekend, but will report back then. They are all purchased in Brazil. I will get some photos of the multimetre readout along with the exact model numbers.