Neutral current issue

[kashifkhan]

we are using three phase ups connected in parallel . one of the ups is giving 56 amp neutral current while other two ups are showing 26 amp and 28 amp neutral current each. common Neutral bus is used for each ups. and there is no load on these three ups.Problem is that with this issue inductive load is not able to run. power factor is 0.5. when i turn my off my one of ups the one giving 56 amp neutral,the other two ups give 5 amp and 3 amp neutral current and inductive load run with power factor 0.85. i want to ask what are the possible causes of it and how to get ride of it? and secondly when run my inductive load through generator with all the three ups running no issue with the inductive load can any one explain?

 

[brian john]

Assuming all three UPS are matched and have the proper interconnects to operate in a parallel configuration my first thought is one of the UPS's has:

An output filter or output transformer issue