• Does a magnetic flow meter need to be earth grounded.

    last modified by aaron.lewin
  • TEFC motor terminal box.

    Does a TEFC motor terminal box need to be sealed on the inside.
    last modified by aaron.lewin
  • light and power circuit in same trunk

    Can i run power  circuit and light circuit in same conduit or trunk of same voltage ?
    last modified by maqsoodasif17
  • Double Tapping Breakers?

    What type of breakers are available today that will allow "Double Tapping" in a residential breaker panel?
    last modified by david.sparkes
  • Pull boxes penetrating walls

    Hi everyone!   We are doing a renovation project and one of our concerns is a pull box penetrating a wall. According to one of the project managers, in Japan's standards, a pull box made of a 1.6mm-thick p...
    last modified by ejlsanpedro
  • is Field Certificate mandatory for unlabeled equipments?

    Good morning   I have a US vendor who is installin paneld made in Ahmedabad, India. The contract was closed by my mechanical colleague and he didn´t take too much care about mechanical devices, but now I...
    last modified by maridul63
  • Type NM cable in EMT Conduit

    What does the NEC state for running Romex (NM) cable through EMT conduit?  I have always been told it was not permitted, but some quick reading on the web makes me think otherwise.
    last modified by lambert.christ
  • Ground outside of device.

    What would be the purpose of the ground being on the outside of the device
    last modified by aaron.lewin
  • Ref : NFPA(NEC) 70 Article 725.49(B).

    NFPA(NEC) 70 Article 725.49(B) pertaining to class 1 cicuit conductors  says "Insulation shall be rated for system voltage and not less than 600 volts" Here I have two queries related to field I/O wiring for PLC...
    last modified by jz2018
  • Garage cable clarification

    Hello, I have a question about a residential garage that I am building. My family is having a detached garage built on our property. It is far from our main house but close to an electrical pole. We plan to have new ...
    last modified by jasinb
  • Verifying that the grounding conductor is correctly sized.

    To whom it may concern,   Good morning from Texas, I would like to verify a decision that I have made with you all. Before I go into detail, allow me to give a brief overview of what I am trying to do. I have be...
    last modified by mberzoza
  • Access/safety requirements for 480V panelboards with no doors

    Does anyone know what regs govern panel location, access, or whether or not 480V panelboards should have doors to protect people from the breakers themselves or risk of shock? 
    last modified by derek.boudreau
  • What is the proper protocol to connect aluminum to copper wire?

    I recently had an electric fire in my house that was remodeled by a licensed contractor and electrician. It turns out that he wired the new copper wire connections directly to the aluminum that makes up the wirin...
    last modified by xxxashworthxxx
  • My 2017 NFPA code book missing pages.

     NFPA 70 missing pages are 561, 564, 564 ,568,569, 572, 573 and 576.  I have two pages of pages 570, 571, with 571 before page 570,  two pages of 574, 575 with page 575 before 574. Curious if anyone e...
    last modified by mdneely@yahoo.com
  • Schoolyard Hazard

    What's wrong here?
    last modified by nec.consultant
  • Electrically Safety Work Condition & Increased Likelihood of Injury

    In NFPA 70E 130.2(2) it states that and Electrically Safety Work Condition must be established if "The employee interacts with equipment where conductors or circuit parts are not exposed but an increased likelihood of...
    last modified by rhogg
  • NFPA 70 - Clarification on Exceptions in NFPA 70 for Electric Substations

    Is a “Substation Control Building” and its electrical system (such as AC wiring & outlets, lighting, etc.) found inside an electrical substation and under the exclusive control of an electric util...
    last modified by david.guzman
  • System Ground TYPE

    Hello,   Is there a way to easily identify the System Ground Type? How can you figure out if you have a Solidly Grounded System, High Resistance Ground System, Un-grounded System, Reactance Ground System? I do...
    last modified by htrpez
  • 208 volts to building ground

    I have a 120/208 panel, I noticed the outlets running off this panel were showing 120 volts from neutral to hot, but when I check the voltage to the building ground I got 208 volt, this panel I'm told was original, 'm...
    last modified by bill.brown

    Hi All,   I am making a 3 Phase power meter using a MICROCHIP IC ATM90E36A. They recommend to use neutral wire as a GND reference to measure voltages at 3 hot legs but in my loads (Air Conditioners) there is no ...
    last modified by arshdeep