410.73 -- Luminaire Disconnects -- What The Heck Does It Cover?!?

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Ladderless

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I apologize for the length of this post, but I've come across an issue the nobody seems to be able to definitively answer. I'll admit that it's a bit self-serving, in that my company manufactures light CFL fixtures (inlcuding recessed downlights) that appear to meet the code in a unique way, along with other safety features.

As far as I can read, there are two classes of covered fixtures (retyped from
the code, only adding carriage returns):

====================
fluorescent luminares (fixtures) that utilize double-ended lamps and contain ballast(s) that can be serviced in place

or

ballasted luminares that are supplied from multiwire branch circuits and contain ballast(s) than can be serviced in place
=====================

Please let me know what you think. the only response I have received from the industry "experts" is that it only covers double-ended lamped ballasts; they seem to ignore the second group outlined above.

Someone I know asked Howard Wolfman of OSI and Chair of the NEMA Lighting System Division. Here was his response:
"It is my understanding that the US NEC Code Panel has concluded that the luminaire disconnect applies only to double ended fluorescents, for all covered luminaires installed after January 1, 2008. Canada, on the other hand, requires disconnects for all luminaires manufactured after June 1, 2007, and effective 1/1/2010, is also adding CFLs, but it is possible that this requirement may be removed from the Canadian Electrical Code."

If this is true, and it only applies to double-ended fluorescents, then I have a few questions:

1- What is the purpose of the second group listed above (after the -OR-)? The presence of a common descriptor ("Contain ballasts that can be serviced in place") would indicate a separate second group, and the absence of the descriptor "utilize double-ended lamps" would indicate it is NOT applicable to that second group.

2- If the purpose of the code is to provide a means for safer fixture maintenance, why does it not apply to CFL's? Maintenance on those fixtures is as dangerous as double-ended fluorescents, aren't they? So I guess it's not OK for people to get hurt while working on double-ended lamps, but fine if they're hurt working on CFLs?

3- All the responses I've seen include qualifiers like "it is my understanding" leading to clouded facts. If it's in the code, then it's there... If it shouldn't be in the code, then it should have been taken out by now, especially since it goes into effect in less than six months.

4- If a building is erected after 1/1/08 that has CFL fixtures that do NOT have the disconnect, and a worker gets electrocuted while working on one of the fixtures, would YOU want to have to explain to a jury why the fixture didn't have the disconnect, given the code as it is written? What would YOU say?

I appreciate everyone's responses.
 
For that second class of fixtures all the manufacturer has to do to be code compliant is to put a label that reads "not for use on multiwire circuits". This rule should not even be in the NEC...it is not an installation rule, it is a manufacturing rule and as such, it belongs in a product standard, not the NEC.
Don
 
That's actually funny... When I had my contacts at Intertek and UL look into the issue, they BOTH came back to me with the same answer: This is clearly just a wiring issue, and NOT a fixture issue. They see the solution that the installing electrician would bo the one to add a disconnect (or wire one switch per fixture -- Yeah, right - Especially since the switch would have to cut the hot, neutral AND ground).

It looks like everyone is pointing to everyone else.

So if my fixtures inherently disconnect before maintenance begins, could I say that they are 410.73 compliant? Even if they are CFL? Or would that not apply?

Moderators note; Link to manufacturers site removed
 
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410.73(G) says "internal or externally".

This means the requirement can be met by either the manufacturer or the installor. . Ultimately it is the installors responsibility to add the disconnect externally if an internal one isn't built into the product.

This is similar to the arc flash requirement of 110.16 which includes the word "field". . That throws the burden on the installor to comply with 110.16 if the manufacturer hasn't already put the label on. . [It is my undrestanding that as of right now, the field marking requirement doesn't require the installor to mark the calorie or protection level # on that label.]

422.51 is an example of the burden for compliance thrown on the manufacturer, "integral part of the attachment plug". . [Even tho we all throw the word "plug" around loosely, in the NEC, the word "plug" never refers to the receptacle. . It refers to the device that is inserted into the receptacle.] . But even for that requirement, the burden for older machines falls on the installor according to the last sentence of 422.51.

Getting back to 430.73(G)
Some manufacturers will undoubtedly offer fixtures with an integrated disconnect ..... for a price. . These fixtures will satisfy this code rule. . But ultimately the burden for this one falls on the installor.

David
 
The harder question to answer is what exactly is required ?

I'm not sure, and I need to find out by Jan 1 because I need to enforce it, whatever it is.

I believe it would be helpful to break this requirement down with well placed breaks in the paragraph in order to understand it. . I'm going to add some breaks and bold highlights below to the first half of the NEC paragraph.

410.73(G) Disconnecting Means. . In indoor locations, other than dwellings and associated accessory structures,

[#1] fluorescent luminaires (fixtures) that utilize double-ended lamps and contain ballast(s) that can be serviced in place

or

[#2] ballasted luminaires that are supplied from multiwire branch circuits and contain ballast(s) that can be serviced in place

shall have [so it's talking about both #1 + #2]

a disconnecting means either internal or external to each luminaire (fixture), to disconnect simultaneously from the source of supply all conductors of the ballast, including the grounded conductor if any.

410.73(G) Handbook Commentary
Section 410.73(G) was added to the 2005 Code with an effective date of January 1, 2008. . It requires a disconnecting means for the following types of fluorescent luminaires that can be serviced in place:

1. Luminaires that utilize double ended lamps
2. Luminaires containing a ballast(s) and supplied from multiwire branch circuits

The disconnect can be either inside or outside the luminaire and must disconnect all supply conductors simultaneously, including the grounded conductor if one is provided. . Exceptions are provided for; hazardous (classified) locations, emergency illumination, cord-and-plug connected luminaires, industrial facilities, and luminaires not supplied by a multiwire branch circuit and in which disconnection does not leave the illuminated space in total darkness.
[end quote]

I need to get a good grasp on the general requirement first before I start into the exceptions. . I hope others post comments here that we can all think about as we think this thru.

David
Click to expand...
 
I agree with everything you said, and appreciate your input... Thanks!

You also bring up a HUGE issue - That of the disconnected ground. Both UL and ETL came back to me saying it's not an issue, because all they need is to make sure they add the neutral to the switching (how easy is THAT to do?!?). They never brought up the issue of the ground. This could make remote switching almost impossible.

I look forward to others' inputs on this.
 
Wouldn't a simple connector (with the hot and neutral wire on it) that plugs into or onto the ballast qualify as a disconnect?

You would just have to make sure the connector guards the live wires from accidental touch.

I would think most fixtures already have this.

Steve
 
Ladderless said:
They see the solution that the installing electrician would bo the one to add a disconnect (or wire one switch per fixture -- Yeah, right - Especially since the switch would have to cut the hot, neutral AND ground).
Click to expand...


The ground does not have to be disconnected.

You also bring up a HUGE issue - That of the disconnected ground. Both UL and ETL came back to me saying it's not an issue, because all they need is to make sure they add the neutral to the switching (how easy is THAT to do?!?). They never brought up the issue of the ground. This could make remote switching almost impossible.
Click to expand...

I believe you are confusing the ground with the grounded (neutral)conductor. Nowhere in 410.73 (G) does it state you have to disconnect the ground.

It does state "to disconnect simultaneously from the source of supply all conductors of the ballast, including the grounded conductor if any."

The ballast does not have a ground wire.
 
earshavewalls said:
There are 5 exceptions to the disconnect rule in (G) of410.73, and the use of connectors is one of them.
Click to expand...

Only if the fixture is cord and plug connected. (See 410.73(G) Exception No. 3)

Chris
 
I think a simple connector complies with the definition of "disconnecting means" in article 100.

If so, a connector would suffice for the disconnect on any fixture.

In other words, I don't think we need exception #3 to use a connector as a disconnect. That might make exception #3 a waste of ink.

Steve
 
Now the question is, does a connector installed within a ballast compartment of a fixture meet the requirment for the disconnecting means to be located "so as to be accessible to qualified persons before servicing or maintaining the ballast".

Chris
 
my two cents and we have discussed this issue up here alot....our inspector feels that the disconnects that you can get from ideal and other manufacturers will meet the requirement for the fixtures with double ended bulbs..On the other issue with the MWBC on the lights they will work as well as long as they are rated for the voltage..they must also be installed correctly so you cannot touch any exposed bare parts..He also feel that it is okay to have them inside of the ballast compartment..I feel it is okay as well due to the many environments in which they are installed every one will know where there at...

Now the way I see this is that..this code is established for safety when working on long banks of fluorescent lights that hang by chains in grocery stores and business's like that..I also see it as a means for big business to have their janitors change ballast instead of calling an electrician...I also see it as allot of hassle for us because we are now responsible to provide a safe way for unqualified workers to take money from us..okay so much for that portion of the soap box...
 
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Energize said:
I believe you are confusing the ground with the grounded (neutral)conductor. Nowhere in 410.73 (G) does it state you have to disconnect the ground.

It does state "to disconnect simultaneously from the source of supply all conductors of the ballast, including the grounded conductor if any."

The ballast does not have a ground wire.
Click to expand...

Exactly

slang word "ground" wire is equipment grounding conductor for fault current only
neutral is grounded conductor for unbalanced operating current

2 totally different animals
As different as Article 200 and Article 250

David
 
x5 question

410.73(G)x5
Where more than one luminaire is installed and supplied and supplied by other than a multiwire branch circuit, a disconnecting means shall not be required for every luminaire when the design of the installation includes locally accessible disconnects, such that the illuminated space cannot be left in total darkness.

"other than a multiwire branch circuit"
If you have a string of fixtures with multiple phase wires running thru the first fixture(s), one of which supplies that fixture and others that just pass thru, it's easy to see that the installation doesn't qualify for the x5 exception that allows a "slave" light to be disconnected at one of the 2 "masters" in that room, therefore you must put a disconnect in every fixture. . But .....

if the circuit enters the room as a 2 wire plus ground to supply the lights in that room, but it originates from a multi somewhere else in the building, could x5 be interpreted as still applicable to the lights in that room ?

David
 
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dnem said:
x5 question

410.73(G)x5
Where more than one luminaire is installed and supplied and supplied by other than a multiwire branch circuit, a disconnecting means shall not be required for every luminaire when the design of the installation includes locally accessible disconnects, such that the illuminated space cannot be left in total darkness.


....if the circuit enters the room as a 2 wire plus ground to supply the lights in that room, but it originates from a multi somewhere else in the building, could x5 be interpreted as still applicable to the lights in that room ?

David
Click to expand...

I would think the circuit supplying the fixtures is a two wire plus ground.
 
If the code making panel did not intend that this disconnect be provided by the fixture manufacturer, why did they put an effective date of 1/1/08 for this rule? That type of dating is normally only done to give manufacturers time to make or modify a product. An example is the 1/1/08 effective date for the use of combination type AFCIs. That product did not exist at the time the 2005 code was written.(not sure it exists now, but that is another thread)
Don
 
don_resqcapt19 said:
If the code making panel did not intend that this disconnect be provided by the fixture manufacturer, why did they put an effective date of 1/1/08 for this rule?
Click to expand...

Very good question.
But if they wanted manufacturers to mold it into there fixture housing, why didn't they say so.

David
 
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