Photo Voltaic DC circuits

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I'm requesting viewpoints on the following installation.

A PV installer has used individual type USE-2, Sunlight resistant conductors from the PV array to the DC disconnect. The individual conductors operate at approximately 400-volts and travel a distance of approximately 90 feet from the array to the disconnect. During that distance they are exposed briefly on the roof, continue traveling behind concrete tile 'eave' shingles, finally traveling, exposed, on the underside of the eave being secured to the truss tails. From the eave height the conductors travel in EMT to the DC disconnect.

Violation or compliant? Please cite reference based on 2002 NEC.


Joe Jones


Senior Member
Re: Photo Voltaic DC circuits


690.7(D) seems like this would have to be considered ,a roofer would think so???



Senior Member
Re: Photo Voltaic DC circuits

690.31(B) says 'type USE-2...shall be permitted in PV source circuits where installed in the same manner as a Type UF multiconductor cable in accordance with Art. 339....

Any questions you have at all about PV systems feel free to contact John Wiles at the Southwest Technology Development Institute (Univ. of New Mexico), (he practically wrote Art. 690). His institute is govt. funded, he makes himself available (for free) to any inspector and he has a great publication he will mail you for free on PV Systems (installation methods, etc.).

John Wiles
New Mexico State University
(505) 646-6105

His publication is:

Sandia Report
'Photovoltaic Power Systems and the National Electrical Code: Suggested Practices'


Senior Member
Re: Photo Voltaic DC circuits

I contacted Mr. John Wiles, of New Mexico State University in referance to his Sandia Report,in dealing with "Photovoltaic Power Systems".

If anyone in forum interested in information on this subject,the 144 page full color report with Inspector checklist can be downloaded at:

Thanx again, dana

[ May 19, 2005, 03:45 PM: Message edited by: dillon3c ]
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