110.26 Working Space about EE

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weressl

weressl

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The question arose: does the working space needs to be a permanent fixture or can it be provided on an as needed basis.

110.26 clearly defines the distances in all three dimensions that need to be provided and maintained as working space about electrical equipment.

I do not seem to be able to find where it specifies that there should be a permanent level surface available at that location. I presume that the available area should equal the width and depth requirements of the space required front of the EE.

  1. What is your opinion?
  2. Does the NEC says anything about this that I seem to be missing?
  3. Could a (removable) platform be made available on an as needed basis and still fulfil the requirements of the NEC?
  4. Is the same requirement applies to both below and above 600V>
 
I am not sure I understand what you are trying to describe. Can you give an example of installed configuration in which an item of electrical equipment does not have a flat surface in front of it?

I think, however, that the answer to your question lies in the code's use of the phrase "and maintained" in the first line of 110.26. The rest of the article talks about specific requirements. My take is that the "and maintained" phrase means that all the subsequent requirements must be permanent.
 
charlie b said:
I am not sure I understand what you are trying to describe. Can you give an example of installed configuration in which an item of electrical equipment does not have a flat surface in front of it?

I think, however, that the answer to your question lies in the code's use of the phrase "and maintained" in the first line of 110.26. The rest of the article talks about specific requirements. My take is that the "and maintained" phrase means that all the subsequent requirements must be permanent.
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Thank you Charlie,

I did not want to give the installation in question so that people can be open minded and think of all the possibilities.

The installation involves 600V class switchgear installed in an insulated sheetmetal prefabricated PowerHouse. The gear has rear access for cable termination via bolted access panels. The gear has its back pushed against the wall and behind each section there is a door in the wall to provide access to the termiantions. The building is elevated and there is no outside walkway planned to have permanent access to those doors but proposed that a scaffold is built on the rare occasions when access is required.

I have a vey firm opinion on this but can't find anything in the NEC to support a position either way.

The space is "maintained" all the time, even in the absence of the permanent standing place in front of the gear is when I asked the same question as you did.
 
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OK, thanks, I understand now. It would be the same as having a switchgear sitting in the middle of a large-enough room, but having it on a housekeeping pad that extends a foot or two (but not three) beyond the footprint of the gear. The maintenance tech could not stand on a level surface in front of the gear, without bringing in some type of temporary platform.

I think it should be a violation, because I think is it not safe. But I need to look again at the words, to see if they come out that way. I'll get back to you.
 
Concur

"Shall be provided" might permit temporary access.
"and maintained" implies the permanence.
"to permit ready ... maintenance" implies Readily Accessible.

Presumably for the sake of floorspace an electrical enclosure could be installed on a nominal "second floor" elevation. A mobile platform with included staircase and lockable positioning could be used to provide temporary access to the equipment. This access could well comply with all NEC requirements short of being permanent.

Delete the "and maintained" clause and change "to permit ready ... maintenance" into "to permit access ... for maintenance" and I think you would be in. I believe you need an AHJ special waiver.
 
Access for cable terminations doesn't need the same working space as front access does (Access for working on live parts).

I think the installation is OK.

Steve
 
All right. Here?s my best shot. Don?t ask me if I think I could sell it to a jury, or to a corporate office that is not interested in spending more money than the law requires.

I believe the installation you described would be a violation of 110.26. My reasoning is as follows:

? The opening sentence of that article requires that both access and working space be maintained.
? You cannot say that both are maintained, unless both are present at all times. If they are not present unless and until you put up scaffolding, then they are not present at all times.
? The requirements for working space do not restrict the height that the equipment can be (i.e., distance from the floor to the bottom of equipment). There are restrictions on the height of overcurrent devices, but the back of the gear has no such devices. So that does not disqualify this proposed installation. The owner could claim that working space is being maintained, in that the required box width, depth, and height are kept clear at all times.
? Article 100 has a definition for ?accessible,? as that word applies to equipment. That definition explicitly excludes circumstances in which the equipment is guarded by elevation. It requires the equipment to admit ?close approach.?
? In the proposed installation, the requirement that access be maintained is not met, since the setup does not admit a worker ?close approach? to the equipment at all times.
 
110.26 Spaces About Electrical Equipment. Sufficient
access and working space shall be provided and maintained
about all electric equipment to permit ready and safe operation
and maintenance of such equipment.
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The working space is well defined in subsequent paragraphs as being all the way to the floor or platform. IMO, if there is not a permanent platform next to the equipment, the working space extends to the floor.

I don't see any reason why you can't supply access to it via a temporary fixture that is safe to work from since it only talks about working space and access, and you have working space and access.

I don't think one can argue the safety issue if a safe temporary working platform is provided.

Accessible, Readily (Readily Accessible). Capable of being
reached quickly for operation, renewal, or inspections
without requiring those to whom ready access is requisite
to climb over or remove obstacles or to resort to portable
ladders, and so forth.
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Besides, think of the millions of bus duct plugs installed in the US. Very few of them would meet the standard Charlie is proposing.

110.26 does not actually say the equipment has to be readily accessible. And even if it did, I might argue that if there is a temporary platform kept in the area, that makes the stuff up on the mezzanine level readily accessible. Its no worse than having to climb a set of stairs. I would suggest scaffolding does not lend itself to be described as anything close to "readily" anything. But a platform on wheels that can be rolled right up, thats pretty ready.
 
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steve66 said:
Access for cable terminations doesn't need the same working space as front access does (Access for working on live parts).
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Consider the points at which the cables are terminated. Are they not "live parts" in themselves?
 
charlie b said:
Consider the points at which the cables are terminated. Are they not "live parts" in themselves?
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Yes, they are normally live parts. However, I think the power would always be shut off before someone accessed the rear of this switchboard. The rear cover is probably only used for the initial terminations, and the occasional checking of the connections. In both cases I would expect the power to the switchboard to be shut off.

The only pare of 110.26 that applies IMO is the very first sentance: "Sufficient access and working space shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment."

IMO, as long as the connections can be accessed by a manlift, or something like that, I don't see a problem.

Steve
 
Thank you all for your valuable insights and contribution.

My take on the issue is as follows.

There are three key words in the following paragraphs I am focusing on:

110.26 Spaces About Electrical Equipment.​
Sufficient access and working space shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.​



Main Entry: pro?vide Pronunciation: \prə-ˈvīd\ Function: verb Inflected Form(s): pro?vid?ed; pro?vid?ing Etymology: Middle English, from Latin providēre, literally, to see ahead, from pro- forward + vidēre to see — more at pro-, wit Date: 15th century
transitive verb
1 archaic : to prepare in advance
2 : to supply or make available (something wanted or needed) <provided new uniforms for the band> ; also : afford <curtains provide privacy> b: to make something available to <provide the children with free balloons>

Main Entry: main?tain Pronunciation: \mān-ˈtān, mən-\ Function: transitive verb Etymology: Middle English mainteinen, from Anglo-French maintenir, maynteiner, from Medieval Latin manutenēre, from Latin manu tenēre to hold in the hand Date: 14th century 1: to keep in an existing state (as of repair, efficiency, or validity) : preserve from failure or decline <maintain machinery>2: to sustain against opposition or danger : uphold and defend <maintain a position>

Main Entry: 1ready Pronunciation: \ˈre-dē\ Function: adjective Inflected Form(s): read?i?er; read?i?est Etymology: Middle English redy; akin to Old English ger?̄de ready, Gothic garaiths arranged Date: 13th century 1 a: prepared mentally or physically for some experience or action b: prepared for immediate use <dinner is ready>
2 a: willingly disposed : inclined <ready to agree to his proposal> b: likely to do something indicated <a house that looks ready to collapse>
3: displayed readily and spontaneously <a ready wit>
4: immediately available <had ready cash>

To sum it up:

It needs to be supplied and preserved from failure or decline and immediately available.




 
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steve66 said:
Yes, they are normally live parts. However, I think the power would always be shut off before someone accessed the rear of this switchboard.
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If we could say that with certainty, and if we could sell it to the AHJ, if we knew that this area was not likely to require maintenance or inspection while energized, then 110.26 disappears in its entirety. But some would argue, and I'd be among them, that a program that requires periodic thermography of energized connections would bring 110.26 into play.
 
Charlie:

What you say may be true, if the connections aren't visible from the front. However, it is also possible that the connections are quite visible (and even accessible) from the front. I think sometimes these rear panels (or side panels in other cases) are only there because it makes it much easier to land all that wire.

Laszlo: I think you are reading way too much into that sentance. I think it is basically meant to keep electrical objects from being enclosed by building structures or finishes, or from being burried in a storage room.

With your interpertation, no electrical equipment would ever be allowed above the ceiling grid.
 
Also consider 110.26(C) Entrance to Working Space.
(1) Minimum Required. At least one entrance of sufficient area shall be provided to give access to working space about electrical equipment.

And refer back to the definition of access and elevation as has been already discussed.

In regard to the original post I have not heard of any requirement for a level surface for the working space. Some have tried to add to the NEC to prevent the installation of panels over stairs but it has not happen yet. (It's not ideal but not forbidden by NEC.)

I believe that the working space and access to the working space needs to be permanently accessible. I have designed electrical rooms which are only 12" deep with a pair of double doors into the corridor. I think this is fine and I have never had an inspector have an issue with it.

What I can't do (at least in this area) is have a door swing into the work space. Avoids oops of someone hitting the EC while he's working. I also think storing heavy boxes and shelves in the work space is not allowed because it's not accessible. But I see this in most buildings I enter.

I think 600V or less requires the work space to be accessible.
If over 600V then it needs to be readily accessible.

I just noticed one thing about the definition of accessible. "...not guarded by locked doors,..." Does this mean the typical electrical rooms or boiler rooms with panels cannot be locked? Or is it allowed since this is the entrance to provide access to the work space. And nothing says the entrance can't be locked. Not really areas I want the public to have access to.
 
steve66 said:
Charlie:

What you say may be true, if the connections aren't visible from the front. However, it is also possible that the connections are quite visible (and even accessible) from the front. I think sometimes these rear panels (or side panels in other cases) are only there because it makes it much easier to land all that wire.

Laszlo: I think you are reading way too much into that sentance. I think it is basically meant to keep electrical objects from being enclosed by building structures or finishes, or from being burried in a storage room.

With your interpertation, no electrical equipment would ever be allowed above the ceiling grid.
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Steve, unfortunately I read what is given to me and break out the dictionary to understand the meaning of the words.

(NEC) Equipment.​
​
​
A general term, including material, fittings,
devices, appliances, luminaires, apparatus, machinery, and
the like used as a part of, or in connection with, an electrical​

installation.

So is 110.26 applicable to all equipment, some equipment and how do I make the distincion, because thge NEC seems to fail in that?
 
charlie b said:
If we could say that with certainty, and if we could sell it to the AHJ, if we knew that this area was not likely to require maintenance or inspection while energized, then 110.26 disappears in its entirety. But some would argue, and I'd be among them, that a program that requires periodic thermography of energized connections would bring 110.26 into play.
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I have seen the same gear used for large motor start that would require periodic disconnect. The main point here is - and this is tried not to define the specific installation in my OP - is that we are looking at a paragraph that is applicable to many different types of installation.

We discover that some types of installations would allow 'this' and others would allow 'that', but so far no one has provided any evidence - to me - that would cite the verbiage in the Code that would allow that to happen.
 
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