Mike Dolt Enterprises
Mike Dolt Enterprises
User: Lyle Nisly, Location: Nebraska
Asked on: Tuesday, February 25, 2025 at 1:41 pm EST
Answered on: Thursday, March 6, 2025 at 9:04 am EST
Question: I would love to speak with the folks that wrote this code and ask them personally what their intent was. I am wondering if I am the only person to question the apparent prevalent interpretation of this code section? 410.110 states that for luminaires recessed in walls or ceilings, We are to comply with 410.115-410.126.... My contention is that the Jbox and whip referenced and allowed in 410.117C ought to allow for a jbox and whip (conduit body) installed for the light for the Tap conductors That are feeding the listed light referenced in 410.118. These items ought to be looked at as integral or necessary for the listed luminaire installation because they sure will not work without it. Currently our state (Im sure it is not the only one) has adopted the position that it means only a jbox UL listed, a part of, and attached to the listed luminaire is allowed up there. This means that either we need to run the tap conductors into and out of the tiny wire space provided by the light (Most of them are pretty small) . This possibly violates wire fill; I have been told that is what some electricians are doing ... (Running their conduit body and then transitioning from conduit to flex in and out to feed the luminaires). Or we need to install access panels to access these 410.117C "Tap Conductor" j boxes, or we need to rough in a j box down into the ceiling pointing down and then whip to the light through the back of this j box (best option of all three) My reason I disagree with the currant interpretation is that ... How is this considered safer? Nor does it help the aesthetics...Almost all flat panels and most other recessed lay in LED lights are all serviced from the top. meaning they must be taken down or to be serviced anyway.How is this code simplifying this? Would not a single 6' luminaire whip That is easily taken out of the circuit and or the light... be infinitely safer than attempting to remove the in and out tap conductors from the light? Doesn't that delete the purpose of the little required light disconnects? The luminaire could be easily disconnected by the required little disconnect in the fixture, removed and replaced.I seem to be in the minority, but I personally think the proper interpretation of this code section allows for the JBox and whip referenced in 410.117C But then moves to 410.118 to state that "All other J boxes" not an integral part of the lighting system is not allowed. I would actually agree that boxes not pertaining to the lights do not need to be there. But to restrict the ones necessary to the function of the lighting circuit is kind of silly. One other thought..., unless we bring the plumbers and sprinkler fitters and hvac trades ect . into compliance of the intent of this code, the purpose and intent of this code is rendered null and pointless (Because they will still continue to consider these lights their access points in a hard lid ceiling.) Has it been incorporated into their code? This interpretation of "no boxes for the lights other than the one on the light itself", is placing undue hardship on the very people who should be qualified to remove the fixtures for replacement or service. Also, it potentially violates the listed manufacturer instructions for box fill on these lights.Now we are telling the Architects/engineers that they must install access panels everywhere thus unnecessarily ruining the aesthetics of the finished hard lid ceiling. I think there needs to be an amendment to this code changing the last 2 words of this code from listed luminaire to lighting system. What are your thoughts? Have a great Day
You raise some excellent points and your frustration with the current interpretation of 410.117 and 410.118 is understandable. Let's break down your arguments and the likely reasoning behind the code.
Understanding the Code Sections 410.110
Establishes that recessed luminaires must comply with 410.115 - 410.
126. This sets the stage.
410.117(C)
This is the core of your argument. It allows "tap conductors" to supply recessed luminaires. This is often done using a junction box and a flexible conduit (whip).
410.118
This section is key to the opposing interpretation. It prohibits other equipment from being located in the same enclosure (plenum space above the ceiling) as the recessed luminaire, "unless the equipment is permitted by 300.22(C) or identified for the purpose." This is where the interpretation gets tricky. The argument is that a separate junction box used solely for tapping the conductors for the luminaire is not "identified for the purpose" of the luminaire in the way the integral box is.
Your Arguments and Concerns1. Safety and Servicability
You're correct that stuffing tap conductors into the small wire compartment of the luminaire can be problematic. It can violate fill requirements and make servicing the luminaire difficult and potentially unsafe. Your argument that a readily removable whip and separate J-box (410.117C) is safer and more practical is compelling.
2.
Code Intent
You question how the current interpretation simplifies anything. You highlight that many LED panels are top-serviced, requiring removal for any work. The "no separate J-box" rule doesn't seem to improve accessibility.3.
Aesthetics and Cost
Requiring access panels to service these "integrated J-boxes" is aesthetically undesirable and adds cost.4.
Manufacturer Instructions
You correctly point out that cramming wires into the luminaire's wire compartment may violate the manufacturer's instructions regarding wire fill and bending space.5.
Other Trades
You are 100% correct that the integrity of any ceiling assembly is often compromised by the other trades. Unless they participate in keeping their equipment out of the lights in a hard lid ceiling it can cause undo hardship on the electrician.6.
Tap Conductors
If we are allowed to run tap conductors with specific ampacities, it seems logical to house them safely and appropriately in junction boxes suitable for their task.7.
Purpose of Light Disconnect
You are right, if you are already bringing power to the light with Tap conductors, you are then taking them off again and disconnecting the fixture again. This renders the light disconnect moot.
Why the Current Interpretation Exists (Likely Reasoning) Plenum Space Concerns
The NEC is very concerned about safety in plenum spaces. These spaces are often used for air circulation, so anything in them has to be fire-rated or otherwise suitable for the environment. The rule is designed to prevent unauthorized or inappropriate equipment from being placed in the plenum.
Simplification and Control
The desire to simplify installations and maintain a degree of control over what's in the ceiling space is a factor. The argument is that if everything is integrated, there's less chance of someone adding something that shouldn't be there.
"Access" to the Tap Conductors
The code specifically allows for Tap conductors to be run from the circuit in a junction box to the light. The fact that it calls them out in the code makes it seem logical that the junction box is required for safety.
Your Proposed Solution and Thoughts
You suggest changing "listed luminaire" to "lighting system" in 410.118. This would broaden the allowance to include equipment (like a separate J-box and whip) that is necessary for the safe and functional installation of the lighting. I think it's a good suggestion.
What You Can Do1. Formal Interpretation Request
Contact your local AHJ (Authority Having Jurisdiction) or state electrical board for a formal interpretation of these code sections. While their interpretation is binding in your area, it may shed light on their reasoning.2.
NEC Proposal
Consider submitting a proposal to the NEC (National Electrical Code) to clarify or amend 410.118. This is a formal process, and you'll need to present your arguments clearly and concisely. Include supporting data (e.g., examples of issues with small wire compartments, potential violations of manufacturer's instructions). This is the most impactful approach, as it can lead to changes in future code cycles.
3.
Talk to Manufacturers
Discuss your concerns with lighting manufacturers. They may have data on wire fill requirements, common installation issues, and potential solutions. Their input could be valuable in supporting your arguments.4.
Document Violations
If you encounter situations where complying with the current interpretation violates wire fill requirements or other codes, document it thoroughly. This evidence can be used to support your case.
In summary: Your concerns are valid and well-reasoned. The current interpretation appears to prioritize a theoretical simplification over practical safety and serviceability in some cases. By pursuing the steps outlined above, you can work to clarify or amend the code to better reflect real-world installation practices and ensure safer, more efficient lighting installations. Good luck! Flag for review