News



3.30.2017

How 2017 NEC Code Changes Impact Atkore Electrical Raceway Products


When considering which electrical raceway product to use for your project, knowing what is allowed by the National Electrical Code® (NEC) is crucial. The NEC is a living document that is on a three year revision cycle which means you need to be aware of any changes as revisions are released. Recently the latest revision cycle was completed resulting in the release of the 2017 NEC. We have reviewed changes that could impact the use of Atkore Electrical Raceway products and have provided and have listed some of the changes that could impact the use of Atkore Electrical Raceway Products.

In Chapter 2 Wiring and Protection. A change takes place in 250.122 Size of Equipment Grounding Conductors section 250.122(F) Conductors in Parallel.

  • 2014 NEC Language: Where conductors are installed in parallel in multiple raceways or cables as permitted in 31.10(H) the equipment grounding conductors , where used, shall be installed in parallel in each raceway or cable. Where conductors are installed in parallel in the same raceway, cable, or cable tray as permitted in 310.10(H), a single equipment grounding conductor shall be permitted. Equipment grounding conductors installed in a cable tray shall meet the minimum grounding requirements of 392.10(B)(1)(c).
  • 2017 NEC Language: If multi-conductor cables are installed in parallel in the same raceway, auxiliary gutter, or cable tray, a single equipment grounding conductor that is sized in accordance with 250.122 shall be permitted in combination with the equipment grounding conductors provided within the multi-conductor cables and shall all be connected together. Cable trays complying with 392.60(B), shall be permitted as the equipment grounding conductor.
  • Analysis of Change: The revision permits standard sized multi-conductor cable to be used where either (1) The cable is installed in cable tray where the cable tray is suitable as the equipment grounding conductor; or (2) a fully sized equipment grounding conductor is used in the cable tray

NEC Chapter 3 Wiring Methods and Materials. The first change takes place in 300.5 Underground Installations section 300.5(D)(4) Enclosure or Raceway Damage

  • 2014 NEC Language: Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in rigid metal conduit, intermediate metal conduit, RTRC-XW, Schedule 80 PVC conduit, or equivalent.
  • 2017 NEC Language: Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in electrical metallic tubing, rigid metal conduit, intermediate metal conduit, RTRC-XW, Schedule 80 PVC conduit, or equivalent.
  • Analysis of Change: Section 358.10 already allowed EMT to be used where it is exposed or concealed, in concrete or direct contact with the earth, in wet locations, damp locations and in cinder fill. Adding EMT to this section does not add a new use for EMT but does bring more attention to the fact that it is allowed for use in these areas.

The next change pertains to all cable articles including MC Cable Article 330 and AC Cable Article 320

  • 2014 NEC Language: No requirement to be listed
  • 2017 NEC Language: Types AC or MC Cable shall be listed. Fittings used for connecting Types AC or MC Cable to boxes, cabinets, or other equipment shall be listed and identified for such use.
  • Analysis of Change: Atkore’s cables and associated fittings are listed to their appropriate standard(S) by UL and/or CSA.

A Change was made to the dissimilar metals section in articles 358, 342, and 344 for Steel EMT, IMC, and RMC respectively.

  • 2014 NEC Language: Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action. Aluminum fittings and enclosures shall be permitted to be used with steel conduit and steel fittings and enclosures shall be permitted to be used with aluminum conduit where not subject to severe corrosive influences.
  • 2017 NEC Language: Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action. Aluminum fittings and enclosures shall be permitted to be used with galvanized steel conduit and galvanized steel fittings and enclosures shall be permitted to be used with aluminum conduit where not subject to severe corrosive influences. Stainless steel conduit shall only be used with stainless steel fittings and approved accessories, outlet boxes, and enclosures.
  • Analysis of Change: Using galvanized steel fittings and accessories with stainless steel conduit can cause a dissimilar metals chemical reaction resulting in corrosion of the fittings. Adding this change to the NEC helps to highlight the fact that this reaction can happen.

There are a few changes in Chapter 5 Hazardous Locations. Section 501.10(B)(1)(1) is the first of the changes involving Atkore products :

  • 2014 NEC Language: All wiring methods allowed in Class 1 Division 1- Which stated Threaded rigid metal conduit or threaded steel intermediate metal conduit.
  • 2017 NEC Language: Rigid Metal Conduit (RMC) and intermediate metal conduit (IMC) with listed threadless fittings.
  • Analysis of Change: Class 1 Division 2 locations are areas in which volatile flammable gases, flammable liquid-produced vapors, or combustible liquid -produced vapors are handled, processed, and used. Threadless fittings have been allowed for use with cables in these areas. Listed threadless fittings for IMC and RMC will provide the installer with more options while providing the required level of protection.

Section 511.8 Underground Wiring in Commercial Garages, Repair and Storage is a new section in Chapter 5.

  • 2017 NEC Language: Underground wiring shall be installed in threaded rigid metal conduit or intermediate metal conduit.
  • Analysis of Change: This is a new section of the code requiring the use of steel conduit in order to protect wiring to these establishments.

There is a change in Section 517.13(B)(1)(2) involving Grounding Of Receptacles And Fixed Electrical Equipment In Patient Care Spaces:

  • 2014 NEC Language: Metal Boxes and enclosures containing receptacles.
  • 2017 NEC Language: Metal outlet boxes, metal devices, or metal enclosures.
  • Analysis of Change: Revised to require redundant ground in all Metal outlet boxes, metal device boxes, or metal enclosures in patient care spaces. Previously required only those containing receptacles.

There is a change in Section 517.31(C)(3)(e) – (formerly 517.30(C)(3)) involving he wiring of the life safety and critical branches.

  • 2014 NEC Language: Listed flexible metal raceways and listed metal sheathed cable is not permitted for equipment requiring flexible connection due to movement or vibration, or connection to luminaires.
  • 2017 NEC Language: Listed flexible metal raceways and listed metal sheathed
    Cable is permitted:

    e.) For equipment that requires a flexible connection due to movement, vibration, or operation

    f.) Luminaires installed in rigid ceiling structures where there is no access above the ceiling space after the luminaire is installed

  • Analysis of Change: Additional uses permitted for Flexible Metal Raceways and metal sheathed cable for Essential Systems in Hospitals has been added. where flexible connections are needed and where lighting is installed in rigid ceilings

Chapter 6 covers special equipment and has a change under section 690.31(A) Wiring Methods for PV Source and Output Circuits.

  • 2014 NEC Language: Where PV source and output circuits operating at maximum system voltages greater than 30 volts are installed in readily accessible locations, circuit conductors shall be guarded or installed in a raceway.
  • 2017 NEC Language: Where PV source and output circuits operating at maximum system voltages greater than 30 volts are installed in readily accessible locations, circuit conductors shall be guarded or installed in Type MC cable or a raceway. For ambient temperatures exceeding 30°C (86°F), conductor ampacities shall be corrected in accordance with Table 690.31(A)
  • Analysis of Change: The change adds MC Cable as an acceptable wiring method to Solar circuits over 30 volts.

If you have any questions pertaining to the National Electrical code and the use of Atkore Electrical Raceway products please contact our Industry Affairs team at the following e-mail address: industryaffairs@atkore.com.