Sched. 80 in industrial?

[safeT1st]

I am installing a pump disconnect (Nema 4x) enclosure at a sewer lift station (class 1 div 2). It is engineered for RMC, but we are at the Oregon coast and the owner wants something rust proof. Can I run Sched 80 thru the class 1 div 2 area to an unclassified area above? This is an industrial establishment with only qualified people allowed to service this. The D.E. has a lockable fence to protect conduits below.

If so, do I need seal-offs before the enclosure if I run the schedule 80 out of the concrete with no fittings before the enclosure. (Enclosure is out of classified area)?

 

[Pierre C Belarge]

In 501.10(B), I do not see an exception or condition that helps you due to being an industrial location.
PVC is not permitted unless concrete encased.


You can use a product called Rob Roy - PVC covered RMC.

There is another product out there that is even more impervious to harsh environments made especially for classified or harsh environments. It is called (I believe I have the correct name) Ocal.

here is a link:

http://www.tnb.com/ps/pubint/index.cgi?a=brands&letter=O-R&region

 

[mdshunk]

There's a good many coated RMC guys lately. Rob Roy, Ocal, Permacote, and Calbond come to mind. One thing with this stuff is plan your runs carefully. If you end up a fitting short, you can't just buzz down to the supply house to pick one up. You can have it overnighted, most times though. Your threading dies need to be bought specially to clear the coating while you thread it.

 

[Pierre C Belarge]

Here is a link directly to the PDF....Warning - this PDF is more the 4MB and for some may be a slow load. But, it is more than worth the slow load.


http://www.tnb.com/contractor/docs/gm8126lr_oc1_1.pdf

 

[Rockyd]

Shoes for the bender, and the dies, both need to be hawged out for PVC coated rigid. Don't forget a can, or two, of the patch for those nasty little nicks.

 

[iwire]

Shoes for the bender, and the dies, both need to be hawged out for PVC coated rigid. Don't forget a can, or two, of the patch for those nasty little nicks.

Check out Pierre's link, they show a lot of nice tools to work with it. :smile:

 

[Goroon]

We use open air "Troughs" then a Motor rated plug connector at the box. The motor in the well is 501 rated and the cord is potted to the motor, with same rating.
Those specifics were discussed and accepted by both Washington county and Multnomath County.. No Seals! No Conduit makes this work as the there are no signicant air gaps in cords of that sive and type to allow gas to migrate to the enclosure in the non classified area. i work for CWS.
See:
501.140 Flexible Cords, Class I, Divisions 1 and 2.
(A) Permitted Uses. Flexible cord shall be permitted:
...
(3) For electric submersible pumps with means for removal without entering the wet-pit. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted.

(B) Installation. Where flexible cords are used, the cords shall comply with all of the following:
[ Read all of 1 through 6]
Exception to (5): Seals shall not be required as provided in 501.10(B) and 501.105(B)(6).

 

[Goroon]

If you use conduit, metal is required and seals also. Ocal was the prefered.

501.10 Wiring Methods.
Wiring methods shall comply with 501.10(A) or (B).
(A) Class I, Division 1.
(1) General. In Class I, Division 1 locations, the wiring methods in (a) through (d) shall be permitted.
(a) Threaded rigid metal conduit or threaded steel intermediate metal conduit.

Exception: Type PVC conduit and Type RTRC conduit shall be permitted where encased in a concrete envelope a minimum of 50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit to grade. The concrete encasement shall be permitted to be omitted where subject to the provisions of 514.8, Exception No. 2, and 515.8(A). Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 600 mm (24 in.) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipment grounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding of non?current-carrying metal parts.

FPN No. 1: Seals are provided in conduit and cable systems to minimize the passage of gases and vapors and prevent the passage of flames from one portion of the electrical installation to another through the conduit. Such communication through Type MI cable is inherently prevented by construction of the cable. Unless specifically designed and tested for the purpose, conduit and cable seals are not intended to prevent the passage of liquids, gases, or vapors at a continuous pressure differential across the seal. Even at differences in pressure across the seal equivalent to a few inches of water, there may be a slow passage of gas or vapor through a seal and through conductors passing through the seal. See 501.15(E)(2). Temperature extremes and highly corrosive liquids and vapors can affect the ability of seals to perform their intended function. See 501.15(C)(2).

FPN No. 2: Gas or vapor leakage and propagation of flames may occur through the interstices between the strands of standard stranded conductors larger than 2 AWG. Special conductor constructions, for example, compacted strands or sealing of the individual strands, are means of reducing leakage and preventing the propagation of flames.

 

[Rockyd]

Had to go to another computer to get the link to work. pretty great sight once I got to it!

 

[safeT1st]

Confused?

Confused?

In article 501.10 B 1 (7) it looks to me like it is permitted to run Sced. 80 instead of RMC. This is a new code, and I am a little unclear of the seal issue though. I usually use 501.15 B 2 ex.1 that states in metal coduits with no union, seals are not required.

We also run cords to the pumps and multitrodes and such, but this is just on the load side of the disconnect.

 

[Fulthrotl]

I am installing a pump disconnect (Nema 4x) enclosure at a sewer lift station (class 1 div 2). It is engineered for RMC, but we are at the Oregon coast and the owner wants something rust proof. Can I run Sched 80 thru the class 1 div 2 area to an unclassified area above? This is an industrial establishment with only qualified people allowed to service this. The D.E. has a lockable fence to protect conduits below.

If so, do I need seal-offs before the enclosure if I run the schedule 80 out of the concrete with no fittings before the enclosure. (Enclosure is out of classified area)?

a conduit entering or leaving a classified location must have a
seal off at the first thread on the conduit after exiting or before
entering the classified area. conduit must be threaded. if using
an ericcson, it must be a fitting listed for that particular occupancy.

if you need corrosion protection, OCAL has vinyl coated ridgid conduit
with epoxy lining. i have never seen pvc ran exposed in a classified
location, ever. how would it contain an explosion, or prevent the
explosion from moving to an adjacent area?

to run ocal, you are gonna need dies turned out to accept the vinyl
jacket without tearing, and if you are using a ridgid 300 or similar
threader, they make knife edged chuck inserts that won't spin as
easily.

bender shoes for your favorite bender are usually available for ocal,
but can damage the vinyl, so oftentimes factory 90's are used instead.
putting wire pulling soap on the shoes will often save vinyl damage.


randy

 

[rbalex]

In article 501.10 B 1 (7) it looks to me like it is permitted to run Sced. 80 instead of RMC. This is a new code, and I am a little unclear of the seal issue though. I usually use 501.15 B 2 ex.1 that states in metal coduits with no union, seals are not required.

We also run cords to the pumps and multitrodes and such, but this is just on the load side of the disconnect.

You may want to recheck Section 501.15(B)(2) Ex.1. "...couplings, boxes, or fittings..." aren't permited in the conduit run either. Actually unions and seals aren't specifically mentioned, but they are "fittings" by definition.

Section 501.10(B)(1)(7) [2008 NEC] does indeed now permit Schedule 80 PVC under very limited applications in Division 2.

 

[weressl]

I am installing a pump disconnect (Nema 4x) enclosure at a sewer lift station (class 1 div 2). It is engineered for RMC, but we are at the Oregon coast and the owner wants something rust proof. Can I run Sched 80 thru the class 1 div 2 area to an unclassified area above? This is an industrial establishment with only qualified people allowed to service this. The D.E. has a lockable fence to protect conduits below.

If so, do I need seal-offs before the enclosure if I run the schedule 80 out of the concrete with no fittings before the enclosure. (Enclosure is out of classified area)?

(7) In industrial establishments with restricted public access
where the conditions of maintenance and supervision
ensure that only qualified persons service the installation
and where metallic conduit does not provide
sufficient corrosion resistance, reinforced thermosetting
resin conduit (RTRC), factory elbows, and associated
fittings, all marked with the suffix -XW, and Schedule
80 PVC conduit, factory elbows, and associated fittings
shall be permitted.
Where seals are required for boundary conditions as
defined in 501.15(A)(4), the Division 1 wiring method
shall extend into the Division 2 area to the seal, which
shall be located on the Division 2 side of the Division​

1?Division 2 boundary.

TECK/CLX type cable with continously welded, corrugated metallic sheeting would also work without seals as long as both ends of the cable in a non-classified area. (Your description wasn't quite clear.)

 

[petersonra]

There's a good many coated RMC guys lately. Rob Roy, Ocal, Permacote, and Calbond come to mind. One thing with this stuff is plan your runs carefully. If you end up a fitting short, you can't just buzz down to the supply house to pick one up. You can have it overnighted, most times though. Your threading dies need to be bought specially to clear the coating while you thread it.

buy a can of the coating and if you have to you can coat your own fittings.