60% fill

[lady sparks lover]

Please explain this below, it's new to me. I've still got a lot to learn.

This is from a engineer who's designing my shop drawing....

Patty - I will change the conduit nipples to 2-1/2 as requested. However, just so that you may know and maybe we won't have to do this in the future, the NEC defines a conduit nipple as being less than 24" in length, and the allowable fill for a nipple per the NEC is 60% as opposed to 40% for conduit.

Best regards,


Project Engineer

[ September 19, 2005, 04:36 PM: Message edited by: lady sparks lover ]

 

[bphgravity]

Re: 60% fill

This comes from Note #4 in Chapter 9 Tables.

 

[infinity]

Re: 60% fill

The actual code requirement is for nipples 24" or less. These short lengths of conduit can be filled to 60% of their capacity as opposed to the standard 40% fill for conduits with more than 2 conductors in them. Also I would note that derating factors do not apply to nipples 24" or less in length.