Definition required

[nealt]

Can anyone tell me where I can find a good definition of the term "totally enclosed raceway", or can someone define that for me in their understanding.

 

[raider1]

Here is the NEC definition of Raceway from Article 100.

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.

P.S. Welcome to the forum

Chris

 

[nealt]

Ok I understand that definition so what about the "totally enclosed" part

 

[rbalex]

Since Chris already gave you the definition of raceway, I'll add that enclosed is also an NEC defined term:

Enclosed. Surrounded by a case, housing, fence, or wall(s) that prevents persons from accidentally contacting energized parts

.
Edit Add: Therefore "totally enclosed" would be "Totally urrounded by a case, housing, fence, or wall(s) that prevents persons from accidentally contacting energized parts." ​

 

[raider1]

I would say a totally enclosed raceway would be something like EMT, RMC, IMC etc....

Things like wireways and surface metal raceways IMHO would not be a totally enclosed raceway due to the fact that you can open the raceway and be exposed to the energized conductors within the raceway.

Chris

 

[nealt]

Well here is the thing. I realise that most of the users of this forum are based in the USA and know the NEC code back to front, but I work in Canada and a lot of the Canadian Code is derived from the NEC.

We use an armoured cable commonly known as Teck, in lots of instances this armoured cable has been installed in underground PVC ducts to get from a to b.

For some reason in the latest version of the CEC (2009), it states that Teck cables can no longer be installed in "totally enclosed raceways" and I am at a complete loss to understand why.

If by "totally enclosed" they mean sealed (airtight) and unventilated then an underground PVC pipe open at both ends probably is not considered "totally enclosed".

Anyone have any helpful suggestions to make.

 

[broadgage]

By "totally enclosed", I dont believe that they mean airtight and not open at the ends.
Virtually all conduits and raceways are open at the ends and this is invariably accepted by inspectors etc.
I would suggest that by totally enclosed, that they mean without openings along the length, i.e. an enclosed pipe or tube not an open channel.

If a cable normally direct buried, or in free air, is enclosed in conduit or similar I would expect that this would reduce the current capacity since heat would build up.
De-rating would be prudent, and perhaps code required, but to ban it entirely seems rather odd.

 

[rbalex]

Well here is the thing. I realise that most of the users of this forum are based in the USA and know the NEC code back to front, but I work in Canada and a lot of the Canadian Code is derived from the NEC.

We use an armoured cable commonly known as Teck, in lots of instances this armoured cable has been installed in underground PVC ducts to get from a to b.

For some reason in the latest version of the CEC (2009), it states that Teck cables can no longer be installed in "totally enclosed raceways" and I am at a complete loss to understand why.

If by "totally enclosed" they mean sealed (airtight) and unventilated then an underground PVC pipe open at both ends probably is not considered "totally enclosed".

Anyone have any helpful suggestions to make.

You are now raising a few subtle differences between the NEC and CEC. First and foremost, the NEC does not consider cable tray to be a raceway; the CEC does. You need to review the CEC definitions. In addition, TECK cable is not a recognized cable construction in the NEC; the closest being Type MC with an interlocked metal tape armor. (Some, but definitly not all, MC or TECK cable constructions are listed both ways)

It would appear the CEC wants to restrict TECK to cable trays or ?open wiring? methods. While they are generally my preference too, I have no idea why there would be the restriction you have mentioned. In my opinion TECK is an excellent construction and the installation you described sounds fine. The 2011 NEC still permits all forms of Type MC in any raceway; so, at the moment your situation baffles me too.