NEIS: Code Question of the Day

NEIS: Code Question for Thu, 9 Jul 09

Thu, 9 Jul 09 00:00:00

Subject: Lightning System Down Conductors Good Morning Charlie, I would like to find out what is the industry standard in terms of selection of the down conduit for the lightning protection system. Which one is better PVC or RGS. Please advise. Thanks Amrita Mishra Project Engineer, PMP Board of Public Work IMGXYZ62IMGZYX

NEIS: Code Question for Wed, 8 Jul 09

Subject: 422.12 and 210.4B Charlie, For a furnace replacement there was a new 2 pole 15A breaker labeled “furnace” and “basement lights”. The homeowner stated that the electrician told him he needed to put the new breaker in. There is a 14-3 NM cable feeding the furnace on one leg and the basement lights on the other. The contractor said he changed the 2 single breakers to a 2 pole to comply with 210.4B. I don't think he would have been required to change it as it was “existing” and he did nothing other than change the appliance on the end of the circuit. Though, this does bring up a few questions. 1. Now that it has been changed, does it comply to 422.12 for the furnace? It is on an Individual Circuit but tied to the lights? So if the basement lights trip, out goes the furnace and if the furnace trips you won't have lights. 2. Since the 25' HVAC receptacle rule came out, It had been common practice to use a 4sq box mounted on the furnace and with a 14-3 NM cable feed the GFCI receptacle on one leg and the furnace switch on the other. Is this still acceptable? Hope to see you at Breakfast in Minnesota, Steve WI IAEI IMGXYZ61IMGZYX

Answer:

Hey Steve, thanks for participating. (1) The furnace is on a multiwire branch circuit and I don't believe that it can be considered as being on an individual branch circuit as 422.12 requires and cannot be individually turned on and off. (2) The furnace is on a multiwire circuit and I don't believe that it can be considered as being on an individual branch circuit as 422.12 requires and cannot be individually turned on and off. When changing or replacing the entire load on a circuit I believe that most jurisdictions require the circuit be upgraded to current Code requirements. The current Code requirements are in place for the practical safeguarding of persons and property from hazards arising from the use of electricity [90.1(A) ]and are the minimum requirements that are necessary for safety [90.1(B)]. Article 100 defines individual circuits as "a branch circuit that supplies only one utilization equipment." The circuit conductors mentioned in your question are used for more than the furnace which does not meet the requirement in 422.12. I'll meet you in the Wisconsin R&R room at the Western Section meeting in Bloomington, Minnesota September 20-23 at the Sheraton.

Section: 422.12, Article 100
Source: Charlie Trout

ANSWERS: Answers are the author's opinions and do not represent formal interpretations of the National Electrical Code.

All answers are based on the latest edition of the NEC, unless the question requests a response based on a specific edition.

CONTACT US: To submit a question, subscribe to Code Question of the Day, or remove yourself from this list, please send an e-mail to codequestion@necanet.org.

ABOUT THE AUTHOR: Charlie Trout is a nationally-known NEC expert and author. He served on three different National Electrical Code-Making Panels and is past chairman of CMP-12. He is also a member of the NECA Codes & Standards Committee. In 2006 Charlie Trout won the prestigious Coggeshall Award, given to recognize outstanding contributions to the electrical contracting industry in the technical and training area.

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NEIS: Code Question for Wed, 8 Jul 09

Wed, 8 Jul 09 00:00:00

NEIS: Code Question for Tue, 7 Jul 09

Subject: NECA-NEIS Code Question of the Day - March 10, 2009 Charlie, I would like a more detailed description of your response to Don from Illinois regarding 680.26(B). I understand that the purpose of the 8-AWG "Equipotential Bonding" is to ensure that voltage gradients are not present in the pool area. This bonding in the pool area is not to provide a path for ground-fault currents, but simply to tie all metal parts together within the pool area to form an equipotential grid. However, the initial question contained a reference to 680.26(B) that I would like clarified "While the code does not require the pool bonding conductor to be run to the service or other panel, it is required to be bonded to an EGC by the rules in 680.26(B)(4), (6) and (7). My understanding of 680.26 bonding requirements is that there is no requirement to specifically tie the "equipotential bonding" conductor to an EGC (Equipment Grounding Conductor) as the question implies. The language in 680.26(B) specifically states that the 8-AWG conductor shall not be required to be extended or attached to remote panelboards, service equipment or electrodes. While we must bond all parts together that are listed in 680.26(B)1 through (B)7, the requirement to tie it to an EGC is not mentioned. The language contained in 680.26(B)(6) seems to clarify this in that when "double insulated" equipment is used that it is not necessary to bond it. The requirement to install the 8-AWG to the pump area is merely for a replacement motor in the future that may not be double-insulated. Could you please clarify your response to mention the "equipotential bonding" requirement to an EGC and the code section referencing it as I am not finding it. My understanding is that there is no need for it unless there is metal equipment contained in 680.26(B)(7) that is within 5ft. of the inside pool wall. In this instance, there could be a connection between the "equipotential grid" and the metal conduit, which is acting as the EGC. Other than that, I cannot find an instance where the two would be connected. Thanks for your code forum as it creates great discussions on safety and construction practices. I make it a part of my daily routine. Tom Sieracki Glen Allen VA IMGXYZ59IMGZYX

Answer:

Hey Tom, Thanks for commenting and let me apologize for this late answer. This one slipped through the cracks and I just ran across it. It's too good a question to ignore. While there is no requirement to specifically tie the "equipotential bonding" conductor to an EGC (equipment-grounding conductor) 680.26(B)(4), (6) and (7) covers equipment that is required to be grounded and must also be bonded to the equipotential bonding grid. This in effect connects them together.

Section: 680.26(B)
Source: Charlie Trout

NEIS: Code Question for Tue, 7 Jul 09

Tue, 7 Jul 09 00:00:00

NEIS: Code Question for Mon, 6 Jul 09

Subject: GFCI protection My questions are about the required locations for GFCI protection. Is GFCI protection required for a dishwasher, disposal, or other under counter receptacles in the kitchen of a residence? Is GFCI protection required for the same under counter receptacles at a wet bar or butlers pantry, assuming the receptacles in question are within a 6' arc of the sink? Thank you for the code question I receive daily. It is first thing I go to when checking my mail. Regards, Bobby Ross Ross Electric San Antonio, Texas

Answer:

Hi Bobby, Thanks for participating. Receptacles installed for disposals, dishwashers or other under counter appliances in kitchens are not required to have GFCI protection 210.8(A)(6). However, GFCI protection is required where receptacles are installed within 6 feet of the outer edge of laundry, utility and wet bar sinks [210.8(A)(7)]. The logic for this is shown in the NEC Handbook, which I am sure you have.

Section: 210.8(A)
Source: Charlie Trout

NEIS: Code Question for Mon, 6 Jul 09

Mon, 6 Jul 09 00:00:00

NEIS: Code Question for Fri, 3 Jul 09

Subject: Article 517 Section 517.30(C)(3) (5) I am currently designing the electrical system in a patient care area. Article 517.30(C)(3)(5) exempts metal raceway for nurse call, telephone/data wiring and other secondary circuits of class 2 or class 3 communication or signaling system. Can the Nurse call wiring and telephone/data wiring be run in the same sch 80 PVC conduit and stubbed 6" above ceiling and use cable tray or J-hook on the ceiling to the system distribution board? Thank you Alberto

Answer:

Hi Alberto, Thank for contributing. Yes, 517.30(C)(3)(5) exempts the secondary conductors of Class 2 or 3 communication or signaling systems from being run in metal raceways, however these systems must comply with the requirements their applicable articles. The requirements of 300.22 must be followed.

Section: 300.22
Source: Charlie Trout

NEIS: Code Question for Fri, 3 Jul 09

Fri, 3 Jul 09 00:00:00

NEIS: Code Question for Thu, 2 Jul 09

Subject: Re: Code Question of the Day - April 22, 2009 Charlie, Thanks for your interpretations of the code. Regarding 250.32B, if a equipment grounding conductor is to be used for grounding and bonding the equipment etc and all you have is a pedestal for an RV, what are you supposed to do with the installed grounding conductor from the ground rod if its not supposed to be connected . I'm confused? Jim Wendt

Answer:

Hey Jim, thanks for participating. The grounding electrode conductor from the grounding electrode is connected to the ground bus in the panel. It is the grounded (neutral) conductor that is not connected to the panel enclosure. The GEC is connected to the equipment grounding terminal bus in the enclosure but the neutral bus is not connected to the panel enclosure. This means that the green screw is not used to tie the neutral bus to the enclosure nor is a jumper connected between the ground bus and the neutral bus. If the equipment-grounding conductor and the grounded (neutral) conductor are connected together a parallel path for neutral current would be established on the equipment-grounding conductor.

Section: 250.32(B), 250.24(A)(5), 550.33(A)(2)
Source: Charlie Trout

NEIS: Code Question for Thu, 2 Jul 09

Thu, 2 Jul 09 00:00:00

NEIS: Code Question for Wed, 1 Jul 09

Subject: need an answer We were recently OSHA inspected. We lease a commercial building and have since 1994. The building was built many years before 1994. The bathrooms did not have GFCIs. Would this not have been grandfathered in? Also, there was a four receptacle electrical outlet, 110-120-volts, 15 amps observed loose in its case and was not continuously grounded when tested with the Etcon 101 electrical tester. What kind of hazard would this be to employees? Also, a 4 receptacle electrical outlet, 110-120 volts, 15 amps was cracked at the plug at the top (hairline crack). What kind of hazard is this to employees? Kathy MacNish, District Manager

Answer:

Hi Kathy, I agree, you need an answer. I don't know how OSHA handles grandfathering. It would certainly depend on the safety related problems encountered. Are you doing some remodel work? Why were you OSHA inspected? Circuits not properly grounded leave open the possibility of shock or electrocution. Hairline cracks may lead to serious breakage and exposure of energized parts that could lead to shock hazard. Receptacles not properly seated and fastened can move and contact other conductive surfaces resulting in potential shock hazard. Come on get real. The requirement for GFCI protection has saved thousands of lives at a minimal cost. The installation of electrical work is a serious business and should be recognized as such.

Source: Charlie Trout