disconnect requirements

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AZIGGY

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Im on a job where I will have (2) 4/0 main feeds pass through (2) 200 amp non fused service disconnects feeding (2) 225 amp 1 phase panels . I know this can not be according to code but the forman on the job is saying its ok because the highest panel amp draw is 172 amps.The forman has 30 plus years in the trade so before I confront him Id like to get some input from other more qualified electricians with some nec code as reference. Iv already mounted the disconnects but we have yet to pull the feeds and I don't want to be shot down by the inspector and have to cost my company more time and money, and plus Im the one who is going to have to fix it.
 
If the 4/0 is copper you are ok, if it is aluminum, it is too small. Where is the panel located in relation to the disconnects? 230.91 requires that where the disconnect does not contain the service overcurrent protective device that the OCPD be located immediately adjacent to the disconnect.
 
AZIGGY said:
Im on a job where I will have (2) 4/0 main feeds pass through (2) 200 amp non fused service disconnects feeding (2) 225 amp 1 phase panels . I know this can not be according to code but the forman on the job is saying its ok because the highest panel amp draw is 172 amps.The forman has 30 plus years in the trade so before I confront him Id like to get some input from other more qualified electricians with some nec code as reference. Iv already mounted the disconnects but we have yet to pull the feeds and I don't want to be shot down by the inspector and have to cost my company more time and money, and plus Im the one who is going to have to fix it.
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Could you clarify what you have there?

I'm picturing service conductors - non fused disconnect - breaker panel being the order of things with 4/0 conductors connecting them, but we don't know if they are copper or aluminum. And you have two sets of each.

Is there a main breaker in the panel? Even if there is, what is the purpose of the non fused switch? Your service disconnecting means must also contain overcurrent protection or have it adjacent to the disconnect. Having it adjacent basically allows for separate fuses, if you have a breaker the unfused switch is not really necessary.
 
Picture a 18' by 18' pad with a 120/240 SES w/ (4) meter bases and 225 amp main circuit breakers. Also on the same pad is a exterior 225 amp service panel. 50 + feet east of the pad is the main building where there are (3) 200 amp non fused service disconnects.(2) go to panels directly on the other side of the wall via 2 1/2 " rigid nipples.The third also pass through the wall and will connect to a 225 amp main service panel on the second floor - that's going to be a fun pull :( (2) panel are 225 amp with feeds coming from the ses, and one is a 100 amp sub panel with feeds coming from the 225 amp exterior service panel via a 2 pole 100 amp breaker. The feeds coming from the ses are 4/0 copper and the feed from the exterior panel are 1/0 . Each set of feeds pass through a 200 amp non fused service disconnect. Now I just can't figure how it would be allowable to connect a higher ampacity rated service feeds and panel via a lower ampacity rated service disconnect. Heck if that the case lets save money and use a 30 amp ahu disconnect- at lease will have fuses. We have yet to receive the guts but I think the only panel with a main panel breaker is the 225 amp exterior panel. By the way thanks for you helpful responses;its appreciated.
 
My immediate thought was that it has to be a violation, however, it appears from 225.39, it might be Code compliant (should have accepted that fact when Don made post #2 :D) If legal, it seems a very poor design, IMO.

That said the entire installation seems to be a violation of 225.30, but there is a lot of wiggle room there in 225.30(B), if applicable.
 
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