• NFPA 70 690.12 RSD and Ground Mounts

    Hello, My organization is troubled by a recent question raised about the Rapid Shutdown Requirements of a Ground mount system which has AC conductors entering a building for interconnection.   In NH the guidance...
    norwichsolar
    last modified by norwichsolar
  • Clarification on XFMR secondary OCPD requirements. 

    When installing a 1300kva Delta 13.8kv primary, 480vac Delta or Wye secondary.  XFMR will have <6% impermanence.  Is it necessary to install a fused disconnect on the secondary of the XFMR with OCPD on th...
    tvogan
    last modified by tvogan
  • Ampacity Derating for Fire Condition 700.10

    I wanted to clarify what the designer is expected to do regarding calculations to show compliance with 310.15 (B) (2) Ambient Temperature Adjustment Factors, especially during a fire condition.   This is al...
    troyk31
    last modified by troyk31
  • NEC 625 to include off road type lead acid vehicles charging systems

    The NEC does not have an article like 625 (electric vehicle charging system) that applies to off-road vehicles, such as electric fork-lifts and golf carts, etc. 625.2 Definitions for electric vehicle, is defined for a...
    david.heiliger
    last modified by david.heiliger
  • 312.2 damp and wet locations

    312.2 says in wet or damp locations to cabinet or cutout boxes shall be mounted so there is at least 1/4 inch airspace between the inclosure and the wall or supporting surface. My question is how to achieve this spaci...
    charlesvanmeter
    last modified by charlesvanmeter
  • GFCI requirement for water closet

    With regards to GFCI requirements NEC 210.8. Requirements for water closets are not addressed specifically. (definition: a water closet is a small enclosed area with a door that contains only a toilet. No sinks, tubs,...
    johnsonb.0671
    last modified by johnsonb.0671
  • Conduit sealing for increased Safety Enclosure

    in our project, increased Safety (exe) enclosure are installed in class I, zone 2 . As per NPPA 70,  Inarticle 505.16 (C):class II, Zone 2 locations, seals shall be located in accordance with 505.16(C)(1) and (C)...
    huab2000
    last modified by huab2000
  • Working Space Requirements 110.26(C)(2)

    Hello,    We are a California Electrical Contractor and we installed a new 1200 amp switch gear section for a retail center. This was a upgrade of a existing 1000 amp switch gear section.    We a...
    corykruip
    last modified by corykruip
  • Double Tapping Breakers?

    What type of breakers are available today that will allow "Double Tapping" in a residential breaker panel?
    david.sparkes
    last modified by david.sparkes
  • Does the NEC allow for the use of nonmetallic electric conduits in plenum of a confined space in a building?

    The NEC don't allow for the use of nonmetalic electric conduits in plenum (open space above false ceiling used for return air) in order avoid the convey of smoke and/or fire to other parts of the building. Is this ap...
    abdulazizabuali
    last modified by abdulazizabuali
  • I'm trying to locate the Code reference that states "Cables cannot use components of another trade as direct support."

    I'm trying to locate the Code reference that states "Cables cannot use components of another trade as direct support." We have a Maintenance person that keeps using the Fire Suppression pipes and Heat Ducts to suppor...
    tmulanix
    last modified by tmulanix
  • Meter main combo wiring

    With a meter main disconnect combo. Using the main lugs from the disconnect (not one of the additional breakers in the M M combo) to run cable to a interior panel board. Would this designate my Interior panel board as...
    charlesvanmeter
    last modified by charlesvanmeter
  • equipment grouding conductor used as a bonding jumper.

    Can you use a equipment grounding conductor as a means of a bonding jumper for conduit. I have always used a separate wire for the bonding jumper.   r.
    aaronlewin4
    last modified by aaronlewin4
  • MC cable for PV installation

    Article 330.12 prohibits MC cable when exposed to mechanical damage. 690.31(D) allows MC cable when intalled in an area that is not readily accessible.  My client wants to install MC cable across the open roof of...
    jeffrey
    last modified by jeffrey
  • Distance between the HVAC DUCT and Power Socket

    As per standard what is the required space between vertical HVAC Duct & Power socket on wall. 
    lllsadiqlll
    last modified by lllsadiqlll
  • 2017 NEC Section 300.10,250.96,20.118(6) Electrical continuity

    What is the meaning of electrical continuity as far as bonding and grounding requirements per NEC?   For example: 30" length of 4" diameter of LFMC on one end of pipe then connects to 60 feet of 4" diameter of r...
    daniel.burr
    last modified by daniel.burr
  • hot Tube installation

    I installed an outdoor  hot tub about a week ago, the outside of the tub is plastic we poured a concrete slab with rebar since the hot tub  is made out of plastic all surroundings of the hot tub a...
    homevisionin
    last modified by homevisionin
  • mounted fuel tank

    hi everybody  i hope you are all ok.... In NFPA-110 chapter 3 in the general definitions, it is mentioned that: 3.3.7.3 Integral fuel tank in EPS systems: Afuel tank furnished by the EPS supplier and mounted o...
    alonazay
    created by alonazay
  • 2017 NEC Section 300.10, 250.96, 250.118(6)

    what exactly does electrical continuity mean in a bonding or grounding sense per NEC.  i have 30" of 4" LFMC on one end of my pipe run that connects to 60 feet of 4" rigid  One end terminates in a switchge...
    daniel.burr
    last modified by daniel.burr
  • Floor Surface Resistance to Ground

    A contract requires measuring resistance of floor surface to ground per "the latest" NFPA 99 edition that covers it. According to reliable sources "floor surface resistance to ground" was removed from NFPA 99 in...
    raymonddeza
    last modified by raymonddeza