Author Topic: Wiring protection - ESA Rule 12-518 & 26-802  (Read 5011 times)

Offline Admin

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Wiring protection - ESA Rule 12-518 & 26-802
« on: March 27, 2015, 01:24:40 PM »
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12-518  Protection for cable in exposed installations
Cable used in exposed wiring shall be adequately protected against mechanical damage where it passes through a floor, where it is less than 1.5 m above a floor, or where it is exposed to mechanical damage.

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26-802 Mechanical protection of conductors
All branch circuit or tap conductors within 1.5 m from the floor shall be adequately protected from mechanical injury.

Offline Porcupinepuffer

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Re: Wiring protection - ESA Rule 12-518
« Reply #1 on: March 27, 2015, 03:17:23 PM »
TSSA Inspector recently reminded us we're not allowed to use drain tubing as a means of protection. It has to be approved electrical conduit.

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Re: Wiring protection - ESA Rule 12-518
« Reply #2 on: March 27, 2015, 04:08:17 PM »
The electricians on my sites use either a rigid or flexible conduit.  One thing I do notice is the electricians only use a plastic wiring connector at the furnace casing, into the junction box.  There is a portion of wiring that is not protected by their conduit where it enters the furnace.  I have never seen an installation fail the ESA inspection but I wonder if that wiring should be protected with a proper fitting.  Technically it's within 5 feet of the floor.  I'm not sure what ESA considers "adequately protected".  They do define the word protected,

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Protected (as applied mainly to electrical equipment) — such equipment is constructed so that the electrical parts are protected against damage from foreign objects entering the enclosure.

The following is from ESA Bulletin 12-19-11,

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Means of mechanical protection may consist of flexible conduit, wood channel or other means which will provide adequate protection.

The following is from ESA Bulletin 26-24-1,

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Can NMSC be installed below 1.5 m above the floor for a residential furnace drop?

Yes, however exposed NMSC installed below 1.5 m above the floor requires mechanical protection as per Rule 12-518. This includes all cable drops to residential furnaces where the cable is not protected by location (e.g. the furnace is mounted directly beside a studded wall, and the cable is run between the studs). Examples of acceptable installations include running the NMSC in flexible conduit or a raceway or replacement of the NMSC with armoured cable (BX) for the drop.

It appears as though not even liquid tight is allowed, so I would agree that drain tubing would also be illegal.  This is strange as the liquid tight we use is much thicker than the flexible conduit the electrician uses to protect the furnace wiring.  The following is from ESA Rule 12-1302(3a),

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12-1302  Use of liquid-tight flexible conduit
(1)  Liquid-tight flexible conduit shall be permitted where a flexible connection is required in dry, damp, or wet locations and where permitted by other Sections of this Code.
(2)  Runs of not more than 1.5 m of 12 trade size liquid-tight flexible conduit shall be permitted for the connection of equipment.
(3)  Liquid-tight flexible conduit shall not be used
  (a)  where subject to mechanical damage;

  (b)  as a general-purpose raceway;
  (c)  in lengths greater than that essential for the degree of flexibility required;
  (d)  where exposed to gasoline or similar light petroleum solvents, corrosive liquids, or vapours having an injurious effect on the outer jacket;
  (e)  under conditions such that the temperature will exceed 60 °C unless marked for a higher temperature; or
  (f)  where flexing at low temperatures may cause injury.

There's an exemption for air conditioners, so I know liquid tight can be used in that case.  The following is also from ESA Bulletin 26-24-1,

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Is liquid-tight flexible conduit permitted for the wiring of a central air-conditioning unit from inside a building to the disconnecting means and from the disconnecting means to the outdoor unit?

Yes. Notwithstanding Rule 12-1302, liquid-tight flexible conduit shall be permitted to be installed in lengths greater than specified in the code for flexibility and simplicity of installation, provided that:

(1)  The liquid-tight flexible conduit is supported as required by Rule 12-1308 using the refrigerant lines for support is acceptable.

Offline Porcupinepuffer

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Re: Wiring protection - ESA Rule 12-518
« Reply #3 on: March 28, 2015, 02:54:39 PM »
We use the grey snap in loomex connectors and use liquid-tight for the 5' protection since we almost always have liquid-tight from a/c installs. We bend it sharp after the connector and strap liquid tight to the furnace and it gives a tight, clean look instead of using an actual liquid tight connector... Maybe it's allowed because it's not expected to be subject to mechanical damage?

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Re: Wiring protection - ESA Rule 12-518
« Reply #4 on: March 30, 2015, 03:58:17 PM »
That sounds right.  You wouldn't expect to see any mechanical damage in a standard furnace room.

Rule 12-518 makes more sense after re-reading it.

I think it's saying the wiring used shall be adequately protected against mechanical damage when is passes thru a floor or when it's within 1.5m of the floor or when it's exposed to mechanical damage.  Each scenario could require a different level of protection.

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TSSA Inspector recently reminded us we're not allowed to use drain tubing as a means of protection. It has to be approved electrical conduit.

Back to the point about not using drain tubing as protection, I noticed ESA Bulletin 12-19-11 says the protection can be "other means which will provide adequate protection."  I don't think the protection has to be approved electrical conduit.  It just has to offer adequate protection.  Would the clear Gorilla tubing we use as drain lines not offer adequate protection?  ESA Bulletin 12-19-11 allows the use of wood to protect the wiring and it's not an approved electrical conduit.

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Re: Wiring protection - ESA Rule 12-518
« Reply #5 on: April 19, 2015, 09:00:08 AM »
ESA Bulletin 12-19-11 says liquid-tight is allowed to be used as protective sleeving,

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NMSC that is used in exposed wiring shall be adequately protected against mechanical damage as required by Rule 12-518 where it is installed at a height of less than 1.5 m above the floor, or anywhere else it is exposed to mechanical damage. This includes a cable drop from a ceiling or a wall to appliances such as furnaces, water heaters, etc.

The preferred method of compliance is to install a junction box and convert to armoured cable for the drop. Other methods include the use of raceways such as flexible metal conduit, EMT, rigid PVC, liquid tight flex, etc as protective sleeving over the NMSC where it drops to the appliance. Note that Rules 12-1500 and 12- 1502 do not permit ENT to be used for this purpose.

NMSC can also be protected by location from mechanical damage. For example, NMSC installed between the appliance and gas pipe drop is considered as mechanically protected by the pipe. The NMSC can be supported to the gas pipe provided it does not interfere with any of the pipe fittings.

Where cable is used for the drop it shall be supported by “band-all” strap, fixture chain, duct cleat material, or similar means that is secured to the building structure and the appliance. The cable shall be secured neatly in place to the support with permanent fastening means such as nylon cable ties or the equivalent. The use of tape is not acceptable as a fastening means.

Where raceway is used for the drop, it shall be secured to both the building structure and the appliance. Bushings and/or box connectors shall be used where the cable enters/exits the raceway or a cabinet as required by Rules 12-906 and 12-3022(3). As an alternative, sharp edges shall be removed from the ends of the raceway and the cable shall enter/exit in a line with the raceway and shall be supported within 300 mm of that point in accordance with Rules 12-508 and 12-510.

Offline Porcupinepuffer

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Re: Wiring protection - ESA Rule 12-518
« Reply #6 on: April 19, 2015, 01:19:58 PM »
Awesome. I've been wanting to buy the Electrical code book to read up on all these wacky codes. But since I don't have a pot to piss in, I need to keep holding off.

Offline reidmechanical

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Re: Wiring protection - ESA Rule 12-518
« Reply #7 on: April 22, 2015, 12:02:32 PM »
Why not just use AC90 Bx cable, that eliminates any question of issues... sure it may cost a couple extra $$, but your only running it from a switch or junction box to the furnace, which in most cases isnt more than 10' anyways. saves the time of dicking around fishing the wires through conduit/liquid tight.

Offline walker

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Re: Wiring protection - ESA Rule 12-518
« Reply #8 on: April 23, 2015, 09:57:25 AM »
I didn't know anyone would use anything other than bx cable.  I never seen anything but it, and I certainly have never seen wires fished through drain tubing, if I saw that I would assume a DIY did it and not a professional.