NEC wire bending space requirements for incoming busduct/conduits to a new 4000A swbd

[fandi]

Hello All,
I'm trying to find in the NEC regarding the bending space requirements for incoming busduct/conduits to a new 4000A 480V switchboard.
Top feed doesn't work because the height limitation 103". Bottom feed doesn't work because the room is already in the basement below grade and it seems that the contractor doesn't want to trench even deeper.
I had to think about entering from the back or the side but I need to know NEC requirements first.
Thanks for you help.

 

[Jraef]

The NEC doesn't dictate wire bending space in equipment, because the NEC is not an equipment design specification, it is an INSTALLATION requirement.
UL does however dictate wire bending space and although the NEC doesn't require UL listing, most State codes will require UL or some other acceptable NRTL, all of whom will use UL's standards anyway.

 

[Carultch]

The NEC doesn't dictate wire bending space in equipment, because the NEC is not an equipment design specification, it is an INSTALLATION requirement.
UL does however dictate wire bending space and although the NEC doesn't require UL listing, most State codes will require UL or some other acceptable NRTL, all of whom will use UL's standards anyway.

The obvious question becomes: where can one obtain a table that states the UL bending space requirements?

 

[Jraef]

The obvious question becomes: where can one obtain a table that states the UL bending space requirements?

From the bus duct or switchboard mfr. But in reality, if your switchboard has main lugs, the gear mfr has to have dealt with the UL wire bending space in the design of the main lugs. So are you trying to do something else? As in something the gear was not designed for?

 

[fandi]

From the bus duct or switchboard mfr. But in reality, if your switchboard has main lugs, the gear mfr has to have dealt with the UL wire bending space in the design of the main lugs. So are you trying to do something else? As in something the gear was not designed for?

No, nothing else.

 

[fandi]

The NEC doesn't dictate wire bending space in equipment, because the NEC is not an equipment design specification, it is an INSTALLATION requirement.
UL does however dictate wire bending space and although the NEC doesn't require UL listing, most State codes will require UL or some other acceptable NRTL, all of whom will use UL's standards anyway.

I think busduct/cables are installed by the electrical contractor and therefore subject to NEC requirements.