Extra Flex 4/0 Cable for Industrial Control Panels
- Thread starter Tim Shane
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As I see it the NEC recognizes MTW as Machine Tool Wiring. I think the main problem you are going to encounter outside of using it as part of listed machinery, is the NEC limitations shown in Art 110.14(C)
- Location
- Illinois
- Occupation
- retired electrician
First if this is a factory assembled control panel, the NEC does not even apply to the internal wiring.
If the conductors are being installed in an application covered by the NEC, then the ampacity of the conductors is per the NEC based on the conditions of use. The manufactures ampacity is most often based on 90?C in free air. It would be a rare case where you could use that ampacity for an NEC application.
Also note that if this is a NEC application, you need wire terminations that are listed for use with finely stranded conductors...something that you often don't see in a manufactured control panel.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Plus you need terminations (including whatever any terminals crimped to the wire may end up attached to) which are rated at 105?C before you can use the 105?C ampacity of the wire.
Good luck on that with most standard components.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
a similar question came up the other day.
http://forums.mikeholt.com/showthread.php?t=161024&p=1560921#post1560921
if it is a UL listed panel, you cannot take advantage of these ampacities for wiring inside your panel unless UL has granted you some special dispensation, which is not impossible.
http://forums.mikeholt.com/showthread.php?t=161024&p=1560921#post1560921
if it is a UL listed panel, you cannot take advantage of these ampacities for wiring inside your panel unless UL has granted you some special dispensation, which is not impossible.
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