There are 120V and 120/208V UPS for office equipment tht plug into wall outlets. These don't require a GEC. Then you have UPS that are large enough to be hard wired and need a GEC. These normally feed a panel for distribution and are considered a seperately derived power source. Now for the question, in a research/medical application, there are power conditoners and UPS that serve just one peice of equipment. The manufacturer spec's the UPS to increase the voltage from 208 to 230V or just to improve power quality. The ups is not connected to anything else, and the equipment does not interact with any othe building utility. The normal output volted is three phase without a neutral. The rare one might have a neutral. Does it need a GEC, or is the mechanical ground the only requirement? Also, These UPS/ power conditoners have their own input and output OCP.
When to supply GEC to a UPS
- Thread starter Danpk
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What does the mfg instructions state for the large hardwired UPS?
What is the manufacturer and model of the power conditioners? Some power conditioners are basically a shielded transformer with a high speed automatic tap changer on the front end - since they are a fancy transformer they are an SDS and need to be grounded like any other transformer.
The reason a lot of medical equipment requires a power conditioner is because the equipment has an voltage tolerance, perhaps +/- 3% or 5%, and the inrush of the equipment itself when it is turned on will cause enough of a voltage dip to cause the power to go out of tolerance on most power systems. It may be possible to have a stiff enough power system to mitigate the voltage drop, but the medical equipment manufacturers know that the cable feeding their equipment is usually long enough to cause the objectionable power dip.
Your power conditioner may be different, as Tom wrote you need to obtain the manual and see what the manufacturer requires.
The reason a lot of medical equipment requires a power conditioner is because the equipment has an voltage tolerance, perhaps +/- 3% or 5%, and the inrush of the equipment itself when it is turned on will cause enough of a voltage dip to cause the power to go out of tolerance on most power systems. It may be possible to have a stiff enough power system to mitigate the voltage drop, but the medical equipment manufacturers know that the cable feeding their equipment is usually long enough to cause the objectionable power dip.
Your power conditioner may be different, as Tom wrote you need to obtain the manual and see what the manufacturer requires.
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