IEEE 142-2007 section 1.9 confusion

[wroggent]

For those who have a copy of IEEE 142 2007:


Section 1.9 is "system grounding for uninterruptible power systems"

I believe the descriptions provided in sections 1.9.2, 1.9.3, and 1.9.4 don't match the figures referenced (Figure 1-38, Figure 1-39, and Figure 1-40).

I agree with the descriptions provided, specifically:

for 1.9.2 Separately derived UPS system; "The UPS output neutral is bonded to the EGC and a GEC is connected to the nearest effective grounding electrode"

and for 1.9.3 Nonseparately derived UPS system; if the UPS does not switch the bypass and output neutrals when phases are switched (during operation of a maintenance bypass switch), then "...the UPS output is not a separately derived system but rather a solidly grounded interconnected system."


I think "Figure 1-38-Separately dervied UPS system" is not showing a bond between the UPS neutral and ground terminal that should be present. Effectively I think it should look like Figure 1-39.

I think "Figure 1-40-Separately derived UPS system serving four-wire plus ground loads" is mislabeled and should be labeled as nonseparately derived.

I think the configuration mentioned is section 1.9.4 is not represented by any of the figures.

What do you think?