• Ground Tied To Neutral Bar. Please Help.

    Good Afternoon,        I have a question hopefully I can get some help on. I was troubleshooting a recepticle in co-op apartment that is not working. I went to the circuit breaker panel and when I...
    jesus.rodriguez1808
    last modified by jesus.rodriguez1808
  • Code Compliance of Existing Installation

    Is anyone aware of a NFPA code/standard or other citable industry authority that generally discusses that code compliance for an existing installation is determined by the code in effect at the time of construction?&#...
    gbstand
    last modified by gbstand
  • Cell tower

    I have existing monopole tower for antenna which is grounded and bonded.   Now the structural engineer is going to place long shaft metal plate metallic on each side of the monopole tower by drilling holes in to...
    apurvadave
    last modified by apurvadave
  • grounding electrode conductor connection to concrete encased electrode

    NEC 2014 Section 250.52(A)(3) states that 1/2 inch or larger rebar bonded by tie wire (20 ft or more) can be used as the grounding electrode. When attaching the grounding electrode conductor to the rebar to be encased...
    apurvadave
    last modified by apurvadave
  • Could someone tell me if this is safe?

    Hello all.   I have an easement on my property that runs from an electrical pole on the road, back, underground about 800 feet to a neighbors yard where it stops at a transformer. There is a creek the runs perpe...
    seve.anderson
    last modified by seve.anderson
  • metallic conduits for pv under roof sheathing

    In search of any reference to installing residential pv system and fastening metallic conduit to and distance required from underside of wooden roof sheathing.
    mkidwell
    last modified by mkidwell
  • UL

    Do the electrical components of a Tunnel Boring Machine for a tunnel construction in Virginia have to be UL approved or listed?. The TBM will be mining in gassy conditions (C1D2)
    ernestorene
    last modified by ernestorene
  • SCCR with control panels fed in series

    I am trying to interpret correctly the logic of the SCCR method suggested in NEC 409.110 (4).b  which is the UL508A SCCR Calculation. According to this method, all the components in the feeder circuit would defin...
    zeno
    last modified by zeno
  • Third Party Certification for Pipe of Aspirating Smoke Detectors

    I am using Aspirating Smoke Detectors in a factory. Do we need Third Party Certification for Pipes of Aspirating Smoke Detectors?
    azad.musfiqul
    last modified by azad.musfiqul
  • transformer pool equipment grounding

    I have water fountain decorative NEC 2014 Section 680 Part V and for lights using pool transformer isolated primary 120V to secondary 12VAC RMS. Lights are no niche 12 VAC RMS.   Following questions: a.  T...
    apurvadave
    last modified by apurvadave
  • Good afternoon, I would like to know if there exists a code, law, or rule that indicates it is mandatory to do electrical safety inspections periodically, at buildings and homes in order to avoid home fires.Thanks in advance. Cordially, Loraine

    Good afternoon, I would like to know if there exists a code, law, or rule that indicates it is mandatory to do electrical safety inspections periodically, at existing buildings and homes in order to avoid home f...
    lorainejulio81
    last modified by lorainejulio81
  • NFPA 72 Form for Mobile / Tablet

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    3 votes
    Great resource here: https://docspace.io You can mobilize your NFPA 72 eform so the you can fill out the NFPA 72 form on your mobile phone or tablet. It even adds additional functionality to it. For exa...
    japagley
    last modified by japagley
  • Fountain that does not share pool water

    I have permanent decorative fountain in ground for aesthetic purpose that does not have water common to pool. I see that per Part V NEC 2014 Section 680.50, Part II which include equipotential bonding only applies if ...
    apurvadave
    last modified by apurvadave
  • main lug sub-panel

    main lug subpanel  I was working on a 200 amp panel and I came across a sub-panel 8 space 8 circuit maxed out  that has an overcurrent protection 2 pole 30 amp with a 10/3wire  the 200 amp is maxed ou...
    homevisionin
    last modified by homevisionin
  • Will a receptacle outlet mounted below a kitchen wall mounted counter top be counted as one of the required receptacle outlets in the 2020 NEC for section 210.52(C)(3)?

    The wording in the 2017 NEC regarding physically impaired and totally flat counter tops at islands and peninsulas has been removed. 
    lfelsch
    last modified by lfelsch
  • NFPA 20:2019 - Sizing Circuit Breaker from Fire Pump Panel

    We are designing to use a circuit breaker with only magnetic unit trip protection for a single fire pump (without a jockey pump).Should the FRAME of the circuit breaker meet the rated current OR...
    bindim
    last modified by bindim
  • LV control  panel primary and secondary  fusing

    In low voltage control panels ( typically 120 VAC PLC panels )  how can the code be correctly applied for fusing from a control transformer to loads such as electronic modules.  One main fuse from the line s...
    jz2018
    last modified by jz2018
  • Hazard Evaluation NEC Dust Area

    Hi, I'm looking for a certified company who could make me a hazard evaluation for a silo area, and manufacturing area too for the cornmeal factory. Could you recommend me one, please? 
    erasmo.salima
    last modified by erasmo.salima
  • Inspection Windows for IR Testing

    At a job location we recently had a conversation on providing viewing / inspection windows on our transformers at a facility,  the client has a great PM plan is place for all the electrical equipment. Test , clea...
    rmheiland
    last modified by rmheiland
  • 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