• PPE for HVAC Technicians

      I work for an HVAC service and installation company providing service on residential, light commercial and industrial equipment. We have acknowledged that our current uniforms are lacking in the correct level o...
    rmiller@hamstraac.com
    last modified by rmiller@hamstraac.com
  • US-Federal low voltage safety reqs.

    Hallo everyone! Can anyone tell me if low voltage electrical safety is regulated on the US-federal level and if so, where (CFR, etc.)? I would really appreciate your support!
    l.buhociu
    last modified by l.buhociu
  • Hot Water Heaters

    Greetings, Are there any NFPA mandated requirements that require HWH for emergency eyewash to be powered from stand-by system bus as opposed to "normal" system bus?  I have a system that has a normal bus supplie...
    stepandmit
    last modified by stepandmit
  • Rationale and Application of 50 V Threshold in NFPA 70E

    Good Day,   In the process of setting appropriate safe work conditions for use on various pieces of electrical equipment, the team at my organization has uncovered some questions on appropriately applying the 50...
    nicholas.harknett
    last modified by nicholas.harknett
  • Ampacities for Conducors in Cable Trays

    Conductors in a cable tray are installed per 392.80(A)(2)(d) and both ends of the conductors emerge from the cable tray and terminate in equipment with 75C rating. Since the conductors are installed per 392.80(A)...
    nsaro
    last modified by nsaro
  • Garage door opener receptacle

    In the 2017 NEC, MUST this receptacle have GFCI protection?   From what I'm reading I cannot determine if they mean ONLY the garage receptacles in "storage areas, work areas, and areas of similar use."
    chiefns830
    last modified by chiefns830
  • What Are You Thankful for?

    I thought that as I close out this work week I would say thank you to all that contribute to making the use of electrical energy safer, more efficient, and easily accessible. Have a blessed holiday ! 
    Steve Benton
    last modified by Steve Benton
  • When did the rule forbidding garage outlets on Small Appliance Branch Circuits begin?

    When did the rule forbidding garage outlets on Small Appliance Branch Circuits begin? I know that it's 210.52(b) in 2014, 220-3(b) in 1974, 1962, and 1959, and 2115-b in 1956.
    david_wise
    last modified by david_wise
  • Minimum Area required for Fire alarm system

    As per NFPA 72, what is the minimum required area of the room or building where fire alarm control system is not required? 
    sheraz.baig
    last modified by sheraz.baig
  • NEC 250.122(B)

    In regards to NEC 2014 250.122(B). [Conductors are based on THWN-2, 75 degree terminations and 86 degree F ambient temperature]:   Question/Condition 1: Engineer selects (1) run of (4) #350 KCMIL copper conducto...
    dmatern
    last modified by dmatern
  • Touchscreen in C1D2 location

    I have a touchscreen HMI display that I want to locate in a Class 1 Div 2 area. The display is not rated for the area so I plan to mount it in a purged and pressurized enclosure. The question is, is that good enough? ...
    thomas.black
    last modified by thomas.black
  • Aerosol Plant Flame detector ?

    Can i use Flame detector for Aerosol plant according to NFPA 30B.
    abrar.b
    last modified by abrar.b
  • i am going to active the deluge system with it and its inside

    i am going to active the deluge system with it and its inside  
    abrar.b
    last modified by abrar.b
  • 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
  • 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
  • 70E question regarding light switching

    I have been asked the following question. My answer would be yes, as long as the equipment is maintained and appears to be working properly. What would the correct response be?   I have a client that has a room t...
    tgammonphd
    last modified by tgammonphd
  • NEC 690.15 -2017

    NEC 690.15 -2017:   Are the inverters required to comply with the requirement of NEC 690.15 -2017, to be located within 10' of the inverter?    
    amin.gomaa
    last modified by amin.gomaa
  • Can a lift be used within the Limited Approach Boundary?

    Can an uninsulated lift be used for electrical tasks such as verifying zero energy, changing light bulbs in up to 480V systems? The 70E states that if ladders are used within the Limited Approach Boundary they shall h...
  • NFPA-70E 130.5 (H) Labeling 2018 Edition

    5 Year Reassessment Due--If there are no changes in the electrical system distribution from Utility provider to end user.  No new equipment, single-lines remain the same, available fault current from Utility prov...
    rbandura
    last modified by rbandura
  • Wire tracer?

    I'm looking to see if there is a industry standard for a wire tracking tool. Need something for indoor use to find wire through all types of standard wall sheeting materials. Live and dead wire tracking. Does anyone k...
    charlesvanmeter
    last modified by charlesvanmeter