Number of Penetrations in a NEMA enclosure
Number of Penetrations in a NEMA enclosure
(OP)
I'm trying to determine what standard specifies the number of holes I can drill into one side of a NEMA enclosure.
I'm pretty sure I read this somewhere but can't remember where.
Imagine you've got a NEMA (lets say a NEMA 4) enclosure and you're either not permitted or can't make penetrations on any side of the enclosure except the bottom. Theoretically I couldn't make enough penetrations to exceed the fill of the box per NEC, but I could make enough penetrations where I'd weaken the structural integrity of the box causing the bottom side to bend.
I thought I read somewhere that the maximum square area of penetrations couldn't exceed 40% of the surface area I'm making the penetrations in.
Any help?
I'm pretty sure I read this somewhere but can't remember where.
Imagine you've got a NEMA (lets say a NEMA 4) enclosure and you're either not permitted or can't make penetrations on any side of the enclosure except the bottom. Theoretically I couldn't make enough penetrations to exceed the fill of the box per NEC, but I could make enough penetrations where I'd weaken the structural integrity of the box causing the bottom side to bend.
I thought I read somewhere that the maximum square area of penetrations couldn't exceed 40% of the surface area I'm making the penetrations in.
Any help?





RE: Number of Penetrations in a NEMA enclosure
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Number of Penetrations in a NEMA enclosure
Don Phillips
http://worthingtonengineering.com
RE: Number of Penetrations in a NEMA enclosure