Feeder Sizes

[mstrlucky74]

So I believe the feeder sizes are wrong shown in DIST BD...even the (2) 225A panel UP-1A & 1B should require 4/0 and the 100A panel should be #2's. How do you determine if a neutral is need for these feeds? Thanks.

 

[Ingenieur]

can't read it
too small

if 120/208 all require N's to derive the 120 1 ph

 

[infinity]

#3 THHN=100 amps

I agree can't read it.

 

[Ingenieur]

looks like (as far as I can discern)
200 A frame/lug
150 A CB (fuse?)
3/0 good for 200A
looks OK to me (can't verify V drop from the info presented)

as long as my 'guesses' as to what it says are correct lol

 

[mstrlucky74]

Trying to attach bigger pic.

 

[Dennis Alwon]

Trying to attach bigger pic.

When I enlarge the screen the image is readable

 

[Dennis Alwon]

I agree the panelboard is rated 225 but the breaker is sized at 150 so 3/0 is plenty good....

The neutral is stated on the plan so you must use that size however there is a 100 amp breaker with 3/0 wire and a #8 equipment grounding conductor. I think that #8 is wrong as it must be upsized since the feeder size is larger than needed 250.122(B)

 

[JFletcher]

Why do the first two panels have 2" conduit and the last 1 1/4" even tho all 3 are using 3 3/0 ungrounded? Only difference in #3 is a #2 neutral vs 3/0. According to this wire fill chart:

http://www.westernextralite.com/conduit-fill-table

you cannot put more than 1 3/0 in any type of 1 1/4" conduit

How does it read (1) under phase legs? Are these single phase 120V only panels? If so, why does the feeder column read in sets?

Also, shouldnt it read 3 phase 4 wires?