Feeder without feeder breaker?

[charlie b]

There is an existing 2000 amp switchboard with a 2000 amp main breaker. An engineer wants to attach a 2000 amp feeder directly to the bus bars, without putting in a feeder breaker. Don?t ask why, or what impact that might have on future operations. I just want to know if there is a code violation in the works. I can?t find one, or at least I can?t find one that I know would stick. I tried 240, including 240.21, and I tried 408. I found a possible issue with 408.3(D), but I don?t know if that is strong enough a basis.

Any other ideas?

 

[iwire]

I see no problem and note that it is no different than double or triple tub panel set ups.

 

[cowboyjwc]

You would have to follow the tap rules.

 

[iwire]

You would have to follow the tap rules.

It is not a tap, the conductors are rated the same as the OCPD.

 

[chris kennedy]

An engineer wants to attach a 2000 amp feeder directly to the bus bars

How does he intend on doing this? Are there means on the existing bus to make more terminations?

 

[iwire]

How does he intend on doing this? Are there means on the existing bus to make more terminations?

I usually just buy lugs and add them on.

 

[kwired]

Panelboards (I realize you have a switchboard) with feed thru lugs are designed for this. making extensions from a feeder with same size conductors is essentially the same thing. The problem you have may be how to connect to the switchboard bus, not feeder or tap rules.

 

[roger]

I have done this a few times, the only thing I did was get a blessing from the manufacturer or the engineer of record and I think you would have the latter covered.

Roger

 

[chris kennedy]

I have done this a few times, the only thing I did was get a blessing from the manufacturer or the engineer of record and I think you would have the latter covered.

Roger

I usually just buy lugs and add them on.

Just wondering if the EE was intending on having the installer drill out the bus to add the new lugs.

 

[roger]

Just wondering if the EE was intending on having the installer drill out the bus to add the new lugs.

I have drilled busses on a number of occasions which was the reason for getting someones blessing, be it the manufacturer or engineer.

Roger

 

[iwire]

Just wondering if the EE was intending on having the installer drill out the bus to add the new lugs.

I drill the bus and move on.

 

[hurk27]

I know this is not the issue, but if the voltage to ground is higher then 150v and the existing service or feeder doesent have GFP, would they now be required to bring this up to code with this extention? 215.10

 

[Wes Smith]

If you drill out the buss, wouldn't that break the UL listing of the panel. Then you would need to have a field UL label.

 

[iwire]

If you drill out the buss, wouldn't that break the UL listing of the panel. Then you would need to have a field UL label.

That is a call left entirely to the AHJ, the AHJ has to decided if the modifications are enough to warrant having UL look at the equipment.

 

[cowboyjwc]

It is not a tap, the conductors are rated the same as the OCPD.

Oh thought it said 200.

 

[charlie b]

I see no problem and note that it is no different than double or triple tub panel set ups.

That is the opinion of another engineer in my office. I have a hard time disagreeing with it. But for the moment at least, I see it as my job to try.

 

[charlie b]

. . . if the voltage to ground is higher then 150v and the existing service or feeder doesent have GFP. . . .

Good question. The voltage is 480/277, and the board does have GFP.

 

[charlie b]

How does he intend on doing this? Are there means on the existing bus to make more terminations?

It is an existing system, it is live, and I don't have any photos of the internals. So I don't have an answer to this question. He did mention a term I had not heard before and do not remember now. I got the impression he was talking about a bar that has 6 holes to land new cables, and that has 1 hole to use to attach the bar to the switchboard's bus work.

 

[Jim W in Tampa]

That is the opinion of another engineer in my office. I have a hard time disagreeing with it. But for the moment at least, I see it as my job to try.

I see it same as others, this is just another section to the panel and is protected by the main.