symmetra lx site wiring fault

[ctferndo_apc]

This was originally posted on APC forums on 5/28/2009

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I still get a site wiring fault even if L1 to N and L2 to N is less han 8%. In fact the difference is less than 1 volt. Please help.

[Erasmus_apc]

This was originally posted on APC forums on 5/28/2009

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A site wiring fault can also be present if the UPS detects no neutral on the input. Additionally, if the input phases are derived from a separate panel/transformer than the neutral that is wired to the unit, this can cause intermittent site wiring faults as well.

Have you checked your system wiring configuration? Both phases, neutral and ground should be wired per this kbase: Answer ID 7059, which can be accessed via the following link:

http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=7059

Your best bet at this point would be to totally de-energize the UPS and firmly reseat the wiring tray in the back of the unit and verify all wiring back to the panel and on the input to the unit.

Has this UPS worked fine in the past or is this a new installation?

[ctferndo_apc]

This was originally posted on APC forums on 5/28/2009

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This is a new installation in the Philippines. But the unit is a US / Japan Symmetra LX 16KVA. We have a 230 volt single phase and I extracted neutral from earth ground which provided 115 v L1 to N and 115 V L2 to N.

[Erasmus_apc · Accepted solution]

This was originally posted on APC forums on 5/28/2009

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The US unit is L1,L2,N,G only per the electrical installation guide, with no exceptions. The Philippines would use the 230v "I" model Symmetra LX which is designed to be used for H, N, G wiring.