Devicenet Cables within the same Wireway as 600 Volt motor powerwires

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metal_pro

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What are the NEC/CSA/UL requirements when you have to run Devicenet Cables within the same Wireway as 600 Volt motor powerwires.
I was under the impression that the Devicenet cable would have to be also rated at 600 volt and not 300 volt?
Do not all wires within the wireway have to be rated for the highest voltage or physically sergregated from circuits of different voltages?
What section of the code covers this?
We just recieved a Square D Motor Control Center with Devicenet and Ethernet devices and both cables are in the same wireway as the power wiring. The salseman told me the devicenet cable is rated for 600 Volts but the connectors only have a 300 Volt rating
 
The connections don't matter, the cable insulation is what matters. As long as the mnaufacturer says there won't be a problem, then I think your covered. I would get something in writing from them stating it is OK, for a CYA.
 
The NEC does not apply to the inards of equipment, only to the installation of said equipment, and to certain performance requirements the equipment might have to meet.

There is no raceway as defined by the NEC contained within an MCC anyway.

Devicenet cabling is generally a class 2 circuit and outside of the MCC has to be routed that way.
 
This is the explanation I got from the MCC Supplier

NEC section 300.3(C)(1) applies to premises wiring, not to the integral wiring of motor control centers. Please see the attached NEC definition of premises wiring, and NEC section 300.1(B).

Thus 300.3(C)(1) applies to the wiring methods used to install electrical equipment; hence field conduits external to the MCC must not have conductors of different voltage ratings. Partly that is to ensure a contractor does not inadvertently connect a 300V-rated power cable, mixed in a conduit with 600V-rated cables, to a 600V source. It does not mean that communication cables inside the MCC have to be rated 600V.

The harmonized standard, UL 845/CSA C22.2 No. 254-05 (Motor Control Centers), and CSA standard C22.2 No. 14-05 (Industrial Control Equipment), do not require communication cable or connectors to be rated 600V where they are not exposed to any live 600V terminals or bus within the MCC.

The communication connector is rated 300V, but does not touch any live parts in the MCC, so it is fine as is.
 
Device net is a class 2 system and can not share the same enclosure, box or raceway with power and branch circuits, it can be in an enclosure if required for termination, but seperation is required.
300.3(C) 1 does not apply see the FPN note and review 90.3
For some reason every electrician knows 300.3(C)(1), but does not see the FPN.
90.3 is the most important rule in the NEC, especially concerning power limited and class II circuits.
 
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