JJspark
Member
- Location
- Denver, Co., U.S.A
Does code allow you to use a 480v as a feed thru for 300v rated wire??
Does code allow you to use a 480v as a feed thru for 300v rated wire??
JJ -- It's a shame that a senoir member response is so vague. Anyway, here's NEC commentary that might be helpful.
Section 300.3(C)(1) makes it clear that the maximum circuit voltage in the raceway, not the maximum insulation voltage rating of the conductors in the raceway, is what determines the minimum voltage rating required for the insulation of conductors for systems of 600 volts or less.
The conductors of a 3-phase, 4-wire, 208Y/120-volt ac circuit; a 3-phase, 4-wire, 480Y/277-volt ac circuit; and a 3-wire, 120/240-volt dc circuit may occupy the same equipment wiring enclosure, cable, or raceway if all the conductors are insulated for the maximum circuit voltage of any conductor. In that case, the maximum circuit voltage would be 480 volts, and 600-volt insulation would be suitable for all the conductors.
If a 2-wire, 120-volt circuit is included in the same raceway with a 3-wire, 120/240-volt circuit having 600-volt conductors, the 2-wire, 120-volt circuit conductors could use 300-volt insulation because the maximum circuit voltage is only 240 volts.
Didn't mean to be vague,
Section 300.3(C)(1) makes it clear that the maximum circuit voltage in the raceway, not the maximum insulation voltage rating of the conductors in the raceway, is what determines the minimum voltage rating required for the insulation of conductors for systems of 600 volts or less.
The conductors of a 3-phase, 4-wire, 208Y/120-volt ac circuit; a 3-phase, 4-wire, 480Y/277-volt ac circuit; and a 3-wire, 120/240-volt dc circuit may occupy the same equipment wiring enclosure, cable, or raceway if all the conductors are insulated for the maximum circuit voltage of any conductor. In that case, the maximum circuit voltage would be 480 volts, and 600-volt insulation would be suitable for all the conductors.
If a 2-wire, 120-volt circuit is included in the same raceway with a 3-wire, 120/240-volt circuit having 600-volt conductors, the 2-wire, 120-volt circuit conductors could use 300-volt insulation because the maximum circuit voltage is only 240 volts.
Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this Code. Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquidtight flexible conduit, flexible metallic tubing, flexible metal conduit, electrical nonmetallic tubing, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.
Though it is not precisely defined I've considered J boxes, pull boxes, gutters, & panels part of the raceway system.
You were doing fine until the very last item. Panels rae NOT part of the raceway.
A J-box, pull box, etc. are all inserted to complete the raceway from the origin - sorce of power - to the end - the user of the power. Devices at either end are NOT part of the raceway.
may occupy the same equipment wiring enclosure,...
Touche good sir,
Does code allow you to use a 480v as a feed thru for 300v rated wire?? Original question seems to suggest the wiring to feed thru from one raceway to another.
But what exactly is an equipment wiring enclosure by the code definition? Would that include a starter panel?
Would running any unrelated wiring through a listed starter panel violate other conditions?
Well, going back to the OP's question, the assertion was made that the quote from the comments on Section 300.3(C)(1) about insulation rating on wires run together in a raceway did not apply because a motor starter panel was not a raceway. I was wondering whether it might be an equipment wiring enclosure instead.Who asked anything about equipemnt wiring enclosure"? Why bring it in into the discussion?
It's 600V or nuthin' baby. :thumbsup:300.3 (C) Conductors of Different Systems.
(1) 600 Volts, Nominal, or Less. Conductors of circuits rated
600 volts, nominal, or less, ac circuits, and dc circuits shall be
permitted to occupy the same equipment wiring enclosure,
cable, or raceway. All conductors shall have an insulation rating
equal to at least the maximum circuit voltage applied to
any conductor within the enclosure, cable, or raceway.
Enclosure vs raceway is a red herring anyway.
It's 600V or nuthin' baby. :thumbsup:
Enclosure vs raceway is a red herring anyway.
It's 600V or nuthin' baby. :thumbsup:
Well, there is no official definition for the term "equipment wiring enclosure" in the NEC that would generate a clear ruling, so it is left to the AHJ. I have had it go both ways. I have had an AHJ call the vertical wireway in an MCC a "raceway", others call it an "enclosure". I have also had them call an MCC bucket an "equipment wiring enclosure", because it is an enclosure that has equipment in it. I don't see how a stand-alone starter would be any different, but I have never tried to run 300V wire into a stand-alone starter.Are you saying that an individual listed combination starter or the vertical wireway of an MCC is an "equipment wiring enclosure"?