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william siegel
04-17-2007, 04:48 PM
Is there any code that would prohibit the bending / curling of the wires like this??

John Arnold
04-17-2007, 04:54 PM
Not sure about your question, but, is that panel mounted directly on masonry? Shouldn't be.

Tim Moreira
04-17-2007, 05:50 PM
Bill,

No answer to your question on the wires, but your camera's date stamp is a month ahead.

william siegel
04-17-2007, 07:37 PM
Tim,

I just like to be ahead of the times.

So far this is all I could find - it is a foot note, which makes it non enforceable.

NECA 1, Article 9, Section N:
n) The length of conductors within cabinets and
cutout boxes shall be sufficient to neatly train the
conductor to the termination point with no excess
(see Figure 11). Allow sufficient cable length for thermal
contraction of conductors to prevent damage of
insulation or dislodging connections.

Jerry Peck
04-17-2007, 09:28 PM
Not sure about your question, but, is that panel mounted directly on masonry? Shouldn't be.


Why not?

It's allowed.

Jerry Peck
04-17-2007, 09:33 PM
Is there any code that would prohibit the bending / curling of the wires like this??

From the NEC.
- 110.3(B)

- 110.3 Examination, Identification, Installation, and Use of Equipment.
- - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

I went back to the manufactures (several of them, including Southwire, one of the largest, they make RomexTM) and the answer is that the conductors are rated for minimum bends with a radius of 4 times the diameter of the conductor (including insulation).

If a conductor (including insulation) is .25 inches in diameter, then the MINIMUM bending radius would be 1 inch, or a 2 inch diameter circle.

Those curly-ques look a lot tighter radius than 1 inch.

John Arnold
04-18-2007, 04:10 AM
Why not?

It's allowed.

Say what? Panel corrosion, is what I've always been told. Dang.

Rick Cantrell
04-18-2007, 04:36 AM
Jerry
I seem to remember it being 10 times the dia. of the WIRE.

Michael Thomas
04-18-2007, 04:44 AM
IMO one important practical implication of workmanship like that - not that you can detect it during a typical home inspection - is that similar kinks and tight bends elsewhere may have further tightened *inside* conduit as they were pulled through various junctions.

Rick Cantrell
04-18-2007, 05:15 AM
Sorry Jerry
You looked it up, I did not.
I'm thinking about small dia wire for alarms and phones.

Jerry Peck
04-18-2007, 05:36 AM
Say what? Panel corrosion, is what I've always been told. Dang.

John,

ALL metallic panel enclosures are made with little raised (out from the back) mounting nubs. Those mounting nubs (I hate to call them 'mounting feet') protrude out 1/4" from the back of the enclosure. When the enclosure is installed on a masonry wall (inside or outside), those mounting nubs keep the back of the panel (are designed to anyway) 1/4" out from the surface of the wall.

Which is why, for panels installed outdoors and in other wet or damp environments, there is supposed to be a 1/4" air space between the back of the enclosure and the wall, and why *the perimeter of the enclosure SHOULD NOT be caulked*. I don't know about your area, but where I go, everyone wants to caulk that space around the outside of the enclosure.

Jerry Peck
04-18-2007, 05:48 AM
Jerry
I seem to remember it being 10 times the dia. of the WIRE.

The NEC, for over 600 volts, specifies '5 times the diameter of the conductor' (including insulation) as the minimum radius. Unfortunately, for 0-600 volts, that was not included.

So, even though the panel enclosures are required to have proper minimum bending space (at 5 times the diameter of the wire size designed to be used), the conductors themselves (for under 600 volts) was not addressed.

Me being me, I had to know, so I called the manufacturers and talked with their engineers. This is what they sent me, it is from the Insulated Cable Engineering Association.

Nick Ostrowski
04-18-2007, 06:56 AM
Jerry, John and I frequent a lot of the same areas for our inspections and most older homes in our area have stacked stone walls which are rather porous. I've seen more than a couple panel boxes that were mounted directly on these walls and had corrosion on and inside the box, on the breaker contacts, and on the bus bars. Whether it is a service panel or junction box, I recommend that they be mounted on wooden boards against the wall.

Jerry Peck
04-18-2007, 08:21 AM
Whether it is a service panel or junction box, I recommend that they be mounted on wooden boards against the wall.

Won't hurt to mount it that way, as long as the wood is PT, but then, the new PT could create a worse problem with corrosion and the metal than the stone wall would. Just a thought.

Instead of mounting it on wood in cases like yours, I would recommend mounting them on Unistrut channels.

About Unistrut (http://www.unistrut.com/about/index.php?P=po_mf)