300v wire passed thru 480v starter panel

[JJspark]

Does code allow you to use a 480v as a feed thru for 300v rated wire??

 

[petersonra]

Does code allow you to use a 480v as a feed thru for 300v rated wire??

if it is separated some how from the 480V wiring.

 

[mwm1752]

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.

 

[petersonra]

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.

a starter panel is not a raceway.

 

[mwm1752]

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.

 

[weressl]

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.

 

[mwm1752]

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.

 

[GoldDigger]

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.

But what exactly is an equipment wiring enclosure by the code definition? Would that include a starter panel?

may occupy the same equipment wiring enclosure,...

Would running any unrelated wiring through a listed starter panel violate other conditions?

 

[mwm1752]

You are able splice conductors of different systems within a single junction box, Can you splice wiring in a panel, swtchboard, starter panel.

Equipment. A general term, including material, fittings, devices, appliances, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.

Would running any unrelated wiring through a listed starter panel violate other conditions? Maybe thru manufactures installation instructions.

 

[weressl]

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.

I had responded to your stipulation, not to the OP.

The OP poses a nonsensical question and everybody, until now, had taken the questions meaning in the way it makes sense: can a 300V insulated wiring - whatever it carries - be passing through a 480V starter.

In this post you're asking another nonsensical variant of the OP. The answer to that is: of course not.

 

[weressl]

But what exactly is an equipment wiring enclosure by the code definition? Would that include a starter panel?

Who asked anything about equipemnt wiring enclosure"? Why bring it in into the discussion?

Would running any unrelated wiring through a listed starter panel violate other conditions?

Don't think so, but again what does that have to do with the price of tea in China?

 

[GoldDigger]

Who asked anything about equipemnt wiring enclosure"? Why bring it in into the discussion?

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.
My second question dealt with whether any other code provisions would affect running an unrelated wire through a "motor starter panel".

 

[Jraef]

Enclosure vs raceway is a red herring anyway.

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.

It's 600V or nuthin' baby. :thumbsup:

 

[GoldDigger]

Enclosure vs raceway is a red herring anyway.
It's 600V or nuthin' baby. :thumbsup:

Leaving only the question of whether or not there would be a compliant way to partition the space to separate the two wires?
Although it sure does sound like making sure the wire has 600 volt insulation is by far the preferred way to go.

 

[weressl]

Enclosure vs raceway is a red herring anyway.


It's 600V or nuthin' baby. :thumbsup:

Are you saying that an individual listed combination starter or the vertical wireway of an MCC is an "equipment wiring enclosure"?

 

[mwm1752]

NEC 2011
312.8 Switch and Overcurrent Device Enclosures with Splices, Taps, and Feed-Through Conductors.
The wiring spaces of enclosures for switches or overcurrent devices shall be permitted be for conductors feeding through or tapping off to other enclosures, switches or overcurrent devices where all of the following conditions are met:

1. The total all conductors installed at any cross section of the wiring space does not exceed 40 percent of the cross-sectional area of the space.
2. The total area of all conductors, splices, and taps installed at any cross section of the wiring space does not exceed 75 percent of the cross-sectional area of that space.
3. A warning label is applied to the enclosure that identifies the closest disconnecting means for any feed through conductors.

The section is new but previous codes have allowed conductors to feed thru. Play nice now.

 

[Jraef]

Are you saying that an individual listed combination starter or the vertical wireway of an MCC is an "equipment wiring enclosure"?

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.

Both cases where the MCC wiring areas were deemed raceway or equipment wiring enclosures, therefore needing 600V rating on the insulation, were regarding the insulation rating of communication cables by the way. Up until recently, Ethernet cables were not rated for 600V, only 300V, yet people were running Ethernet cables in MCC wireways and into buckets. Some inspectors bounced that. Rockwell had to develop their own 600V Ethernet cable as a result, then so did Belden. More recently, inspectors started bouncing the 600V Ethernet cables in the vertical wireways, because they were AWM rated, meaning they did not have a vertical flame test performed. So Rockwell went back and got a PLTC listing on theirs (Power Limited Tray Cable, which requires the vertical flame test). They are now the only ones that have that, but I imagine that this is going to change as more and more companies move toward Ethernet control.

So bottom line, we can parse out the terminologies all we want, but the SAFE approach is to use the "highest voltage" litmus test, you can't go wrong with that.

Re: barriers
I have to say, I have seen an instance where the inspector allowed a steel gutter put INSIDE of an enclosure to act as a barrier to section off 300V and 600V rated conductors. If you think about it, when you have a device that is mounted inside of a control panel with something like a comm port on it, chances are the conductors BEHIND that comm port are not 600V rated. But if it's not open, i.e. it has a housing, there's your barrier.