• Commercial Outlets

    Can someone point me to the specific section of the NFPA 70 that requires 120V outlets in commercial applications to be upside down (with the ground mounted upward)?  The usual answer I get from electricians is s...
    last modified by fahrquad
  • 210.52(B)(1) receptical outlets served

    Is 210.52(B)(1) saying the two or more 20 ampere small appliance branch circuits required by 210.11(C)(1) will supply all outlets covered in 210.52(A)? Or does shall serve all wall and floor receptacle outlets covered...
    last modified by charlesvanmeter
  • NFPA  70, Art 501.5 (E)

    In NFPA 70, Article 501.5(E), 1 For a Class I Division 2, Terminations - it says cables entering an enclosure required to be explosion proof shall be sealed at the point of entry.   A squirrel cage induction mot...
    last modified by dnowicki
  • 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...
    last modified by charlesvanmeter
  • New Emergency disconnect question

    I just recently installed an UG meter socket and came into a home laterally to (2) 200 amp main breaker panels.  My permit was pulled after 1/1/2020 so I totally understand the new code enforcement of having an ...
    last modified by joepeltier99
  • Testing of a non-UL certified transfer switch prototype

    Hello all!   I have designed and built an automated battery transfer switch that currently fits into a 70 AMP breaker box. The current setup is home breaker box -> Romex -> device -> Romex -> breaker...
    last modified by jeremiah
  • NFPA 70, Article 690.31

    I need assistance with interpretation of the following article.  My contractor is using the following Code exception to omit labeling on PV string wires.  Their logic is that each string wire is is pre-fabri...
    last modified by tasha_mccarter
  • Should a floating ground system chassis be connected to Earth Ground? 

    I have a mobile Radar system, with internal generator, mounted on a truck that was designed and built with a floating ground. When the system is removed from the truck and is sitting on the ground, should the system c...
    last modified by anthony.becker
  • IBC vs NFPA

    Hi All,   In what jurisdictions/instances is the International Building Code enforced? It appears the IBC is more stringent than NFPA codes that I have come across, at least for electrical requirements.   ...
    last modified by stepandmit
  • Wireway Classified as "Free Air"

    Can a wireway be classified as a "Free Air" environment if there is 125 scfm of airflow through it?
    last modified by rayk
  • 2-prong & 3-prong outlets

    I just moved into an older home where many of the outlets are 2-prong only. My brother in law says that replacing the outlet with a 2-wire GFI outlet would meet electrical code and does not require the ground wire. An...
    last modified by cpypdx
  • 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,...
    last modified by johnsonb.0671
  • Questions about 120v breakers. 

    I am an electrical novice.   In and industrial setting, is it required by NFPA 70/70E to lockout a 120v standard breaker (like a household breaker), where the breaker has not been designed to take a lock? Is a ...
    last modified by shaney
  • 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)...
    last modified by huab2000
  • NFPA 110 7.2.2

    In regard to NFPA 110 paragraph 7.2.2. I have a hospital facility that has an open roof equipment yard that contains the EPS as well as an air cooled chiller and chilled water pumps. The EPS is located in its own encl...
    last modified by stella
  •   EPS outdoor

    According to NFPA 110 2016 edition & NFPA 99 2018 edition. Level 1 building.   I have an electrical room, indoor, 2hr FR separation from the rest of building. Normal service entrance more than 1000 amperes an...
    created by jrojas
  • Determine available arc fault value

    I am currently supporting development of a contractor electrical safety program w/ implementation of NFPA 70e. My question is regard determination of  Fault Current (Available) in order to satisfy the use of...
    last modified by tdotts
  • LED lighting in powder paint room

    In a Class II, Division II area inside a powder paint spray room( not a booth), will I need to put in dust tight LED lighting. Some of the SDS's on the powder paint mentions combustible dust but we do have a dust coll...
    last modified by sammyc
  • 2017 NEC 700.3(F) and Fire Pumps

    Do the requirements of the 2017 NEC article 700.3(F) apply to fire pumps?  Fire pumps are mentioned in the code commentary but are not referenced in any other part of article 700.  They are often served from...
    last modified by rbush
  • Why have I been banned?

    Can't post in electrical or industrial hazards forum.
    last modified by chiefns830