This is a new 200 amp install. The city inspector says separate the N&G’s. The electrician says they do not need to be separated because, there is no sub panel.
???
Neutrals and grounds cannot share the same terminations. They must be separated, but they are required to remain bonded (assuming this is the service equipment). The absence or presence of a sub panel is irrelevant, and the electrician is incorrect.
You can bet that Jeff is typically “on the money”. I agree.
Now from what I understand from the electrician has been in the field for over 30 years… Neutrals and grounds can share the same terminals where the main disconnect is… But cannot share the same terminals in a sub panel…
Not true. Same terminal strip(bus) yes but neutrals must be under their own connection point by themselves.
It never was technically permitted though it was common practice.
Your electrician is wrong.
“Terminal bars,” yes. “Termination lugs/screws,” no.
Doing it wrong for thirty years does not make it right…
See NEC 408.21
Article 408 (384 in 1999 NEC) Low Res - Modem Hi Res - Cable/DSL Page 4 of 5
Switchboards and Panelboards
408.21 Grounded Conductor Terminations
Intent: This new section should ensure that grounded (neutral) conductors terminate within the panelboard to an individual terminal. This has been a UL requirement (UL Std. 67 – Panelboard Standard) for some time, and the addition to the NEC is intended to bring this information to the installers. Technically, this is covered by 110.3(B), which requires all equipment to be installed in accordance with the manufacturer’s installation instructions and markings, but nobody knew it existed. UL Std. 67 (Panelboard Standard) permits up to three 10 AWG equipment grounding conductors to terminate on a single terminal, if the terminal is marked for this purpose. Figure 408-3
The intent of this requirement is to ensure that the grounded (neutral) conductor of a multiwire branch circuit is not momentarily disconnected, which could result in the destruction of electrical equipment and fires from overvoltage.
http://www.mikeholt.com/onlinetraining/page_images/1016755350_2.gif
I’m sorry I read this wrong… Yes not under same lug
So! are you are saying they can be on the same bar , but not together under the same screw ?
Same as a double tap, they can not share a lug.
Yes.
But on the same bar (bonded) only at the service equipment (“Main Panel”).
The electrician has seen the light. He now agrees.
Sometimes you can teach an old dog a new trick.
But the drawling Mr Larson provided says it’s okay for two green or barewire grounds to share a lug.
I
It’s a bit different than a “double tap.”
In a “double tap” (two wires under one lug of a breaker), the breaker listing does not allow for two conductors under one lug. The term “double-tap” is simply a slang for an improper breaker connection. There are breakers that allow for multiple conductors.
On a grounding terminal, the panel listing allows for multiple grounding conductors under one lug. However, both the panel listing and the NEC prohibit the termination of more than one grounded conductor under one lug.
I used to carry copies of these to hand to anyone who had the urge to argue with me on this point. When I used to do home inspections I also included on in the report package and it saved me from many annoying phone conversations.
In years gone by the problem was the term “neutral” as it is used in the paper you attached. Jim calls it the neutral but the NEC calls it the grounded conductor.
A true neutral is only used with a multiwire circuit such as a dryer or range or any circuit where the white is used with more than one hot. The white conductor used in a 120 volt circuit is not a neutral but is the grounded conductor as outlined in Article 200 of the NEC.
I had a chance to talk with Jim in Raleigh NC when he first sent in the proposal to have the verbiage added to the NEC for the one neutral one screw rule. I tried my best to get him to change the word neutral to grounded but alas it was futile although through the comment stage the verbiage was changed to grounded. Jim still to this day calls it the neutral conductor.
Using the verbiage found on the old panel covers one would be confused as to just how many of the white conductors that could land under one screw as most old panels would use the word “ground” when they were actually talking about the equipment grounding conductor.
If Article 200 Use and Identification of Grounded Conductors is applied to the verbiage found on the panel cover then one could argue that more than one is allowed under one screw as this is exactly what the NEC calls the neutral as we have come to call it. Yes this is a play on words but is that not what the NEC is calling the neutral, “grounded”?
When I am called to do an evaluation of an electrical system and I find more than one white conductor or one white and an equipment ground under one screw I point out this as a code violation but I also add my comment that this is only a safety hazard when the conductors are of a different size or should the circuit need to be worked on. It has no effect on the safety of the system under normal operation. The terminal as outlined in the verbiage on the panel cover is approved for more than one conductor and this is no different than having a breaker with two or more places for terminations except for when it must be removed for one reason or another which at that time could be a hazard to the system or the person removing the conductor.
If we look at NFPA 70E and the requirements of OSHA the white conductor should never be removed from a panel that is energized unless paper work is filled out explaining why this work has to be done while the panel is energized, a hot work permit must be on record in order to work in an energized panel. Should something go wrong while working in a hot panel the person doing that work is in that panel is in deep water without the energized work permit and this includes Home Inspectors removing the covers from energized panels.
NFPA 70E was written due to a request from OSHA as a safety guide to working on or around electrical equipment. It is the standard that OSHA uses to enforce their rules.
**130.2 Electrically Safe Working Conditions. **
Energized electrical conductors and circuit parts to which an employee might be exposed shall be put into an electrically safe work condition before an employee performs work if either of the following conditions exist:
(1) The employee is within the limited approach boundary.
(2) The employee interacts with equipment where conductors or circuit parts are not exposed, but an increased risk of injury from an exposure to an arc flash hazard exists.
Electrically Safe Work Condition. A state in which an electrical conductor or circuit part has been disconnected from energized parts, locked/tagged in accordance with established standards, tested to ensure the absence of voltage, and grounded if determined necessary
As can be seen from NFPA 70E the panel cannot be opened and someone work on that panel unless the panel is de-energized therefore the need to have only one white wire under one screw is mute based on the verbiage outlined by Mr. Pauley.
Hasn’t the NEC included as part of the definition of a neutral a conductor wording that would make it applicable even in a two wire circuit?
From the 08 handbook
The definition of neutral conductor and the definition of neutral point are new for the 2008 Code. These terms were added so that the appropriate conductor could be identified whenever this term is used in a requirement such as in 250.26 and 250.36. The proposed definition is derived from the IEC definition of neutral conductor and the IEEE C57.12.80-2002 definition of neutral point. The proposed definition was adapted to NEC language and was expanded to cover the various cases relevant to the NEC.
It is important to remember that the neutral conductor is a current-carrying conductor. Many believe that, because the neutral conductor is a grounded conductor, it is safe to work on it while it is energized. This is a very dangerous practice that has led to many serious electric shocks.
Notice that the neutral is a current carrying conductor in a two wire circuit therefore not neutral.
Jim made his proposal for the 2002 code cycle before the new definition of neutral conductor was accepted
I’m confused, are you saying under the new NEC wording or the old? Seems to me that a white conductor in a two wire circuit meets the definition of a neutral in the 2011 NEC.