Aboutcleggsan Expertise All technical areas of Electronics Engineering.
Experience BSEE, MBA, Design, R&D, University Research.
Senior Life Member of IEEE. Life Fellow of AES.
Organizations IEEE, Consumer Electronics Society, Audio Engineering Society.
Broad teaching experience; work experience mostly in consumer electronics and conversion from analog to digital technologies. Pioneer in digital audio at all levels.
Question Dear all
1.Why cant we connect UPS neutral with the main neutral bar?
2.How do we check at the UPS the neutral is link to the main neutral?A
few weeks ago,one vendor did take some voltage measurement,but I was
not there to see how he did it.From the reading he concluded the UPS
neutral link to main neutral.How did he know that?
3.What are the effects connecting the neutrakls together?
Answer 1. You can if you want to. However, then it is tied to the supply lines through the ground and certain fault conditions will damage or give erroneous grounding to the ups system. So, they are intentionally kept separate so as to provide the ups ability to stay independent of the supply line with any kind of interruption.
2. If you measure the voltage between the two grounds it can tell you if one or the other is floating too high or out of range.
3. See no. 1. It is a safety and design criteria to keep them separate in most cases.
You really should direct this question to the specific UPS manufacturers technical people; not all UPS systems are designed the same. Different criteria and sensing methods are used by various manufacturers. The technical specifications are quite different from unit to unit.
