During a recent pre-drywall inspection, I came across this setup where multiple conductors were tightly bundled together above the panel (photo attached). I’ve heard multiple times this could restrict heat dissipation and potentially lead to overheating, especially if the bundled length exceeds 24 inches and includes several current-carrying conductors.
I wrote it up as a concern for potential overheating due to reduced ventilation and suggested evaluation by a licensed electrician. However, the builder pushed back, saying they “always do it this way” and have never had any issues.
Curious to hear how others approach this. Would you call this out in your reports?
Appreciate any input or perspectives on how you handle this.
Jeff, using the rules in the NEC the panel would need to be surface mounted in order to use the large conduit as a sleeve for the cable entry. There are also other requirements for the sleeve.
Going by what is accepted. Just like allowing a ground and a neutral under the same lug. You can call it out all day, but the AHJ will back the electrician.
From memory, bundling load carrying circuit cables can be cited when there are 9 or more current carrying conductors, that are run together for 24 ins or more.
Exceptions. How much of the run can be considered to be bundled? If it is less than 10’ or 10% of the total run (which ever is less), The exception to 310.15(2) allows you to ignore the lower ampacity of the derated section.
There is an orange tubing to the right. Kitec pipe?
This is what I remember as well. Then, it gets really complicated since the “fix” is to de-rate the conductors meaning the circuits are set up so the wires don’t carry the max current so they don’t get as hot. We’d have no way of knowing if/when they were de-rated and it’s really too far and too complicated of a road for us to go down in most cases.
Something that really helped me understand the concept was once someone got lazy and wired an attic fan with a 25’ spool of romex and just pulled from each end, leaving probably 20’ of the cable coiled in the pack. The plastic package wrapping had melted and the outside plastic of the wire was burned in places.
I once called OP’s exact situation and got questioned on it. The Codecheck books have a picture of this exact thing (wires clamped at a single, short pinch point) with a circle and slash calling it wrong. They are incorrect from everything else I’ve learned. It’s not wrong until the 24", etc.
I agree with others that this is a non-issue. I wouldn’t call it out as a defect.
The only residential wiring that I’m aware of where heat dissipation is a concern is K&T, which is why I will always call it out as a potential fire hazard if I find it installed under insulation.
My pleasure Eric.
Been calling out bundled circuit cables for quite some time. Well over 10 years if not longer.
Here is the narrative. Observation. Bundled lighting and equipment circuit cables above the service panel.
Electric circuit cables not fastened within 12" inches of the cabinet. Recommend: Further evaluation by a licensed electrical contractor.
Act upon any recommendations therein.
Bundled circuit cables refer to multiple electrical wires or cables that are physically grouped together and bound or secured, usually for ease of handling, installation, and to maintain a neat, organized appearance.
If those cables are only bundled in one location then the bundling is less than 24" so nothing is required to be done. Ampacity adjustments may apply if the cables are bundled for more than 24" which in this case they are not.
