Is it exposed to sunlight?

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sketchy

sketchy

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MN
If I install EMT on the racking of a roof mounted solar array, UNDER the PV modules, is this considered to be exposed to sunlight?
 
Do the PV modules have quick disconnect cables to allow them to be removed for servicing or is it a high voltage DC string?
 
sketchy said:
If I install EMT on the racking of a roof mounted solar array, UNDER the PV modules, is this considered to be exposed to sunlight?
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Exposed to sunlight in NEC usually refers to the conductors or the jacket, regarding UV damage, so for that part with EMT it does not matter.
If you are looking at temperature derating factors for conductors in EMT on a roof, the part of the EMT totally shaded by the array would not be exposed to the temperatures listed for that same distance above a roof and exposed. The latter table factors in both direct heating and air heating from the hot roof.
But it would not hurt to use those same derating factors anyway as it would allow you to run the same wires and EMT exposed part of the way without the inspector freaking out.
 
~ : ~

Article 310.15(B)(2)(c), in the `08 NEC, requires an
adjustment / derating, because the raceway(s) are
installed above the rooftop!.........Also, see Table
310.15(B)(2)(c).

~ : ~
 
But the EMT will be shaded by the modules. So to me that means out of direct sunlight.
 
sketchy said:
But the EMT will be shaded by the modules. So to me that means out of direct sunlight.
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But nevertheless, above the roof. Look at the exact wording of the rule: 310.15, 2011
...exposed to direct sunlight on or above rooftops
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That seems to support you completely, but I would make sure that at no time during the day can sunlight get past the array to touch any part of the EMT run.
YMMV.
 
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GoldDigger said:
But nevertheless, above the roof. Look at the exact wording of the rule: 310.15
That seems to support you completely, but I would make sure that at no time during the day can sunlight get past the array to touch any part of the EMT run.
YMMV.
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IMO, some direct rays of sunlight getting through the "cracks" of the array should not satisfy the condition... but ultimately determined by AHJ. However, 310.15(A)(2) Exception can be argued as negating the direct rays portion.
 
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Does this array move? If not, the sun travels more than 180 degrees during the summer. It could get early morning or late evening sun from the NE and NW.
 
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