Q&ACompliance with Article 690.31(A) of the2008 NECReadily accessible? To comply with the newrequirements in Article 690.31(A), you could raisethe height of a pole-mounted array; for groundmountedarrays, you must use fencing or othermeans to obstruct access to any exposed wiring.In the 2008 Code cycle, Article 690.31(A)concludes: “Where photovoltaic sourceand output circuits operating at maximumsystem voltages greater than 30 volts areinstalled in readily accessible locations, circuitconductors shall be installed in a raceway.”The NEC Handbook elaborates: “Most PVmodules do not have provisions for attachingraceways. These circuits may have to bemade ‘not readily accessible’ by the use ofphysical barriers such as wire screening.”Most integrators do not install moduleswith conduit ready junction boxes becausethese modules are limited in availability andtend to have low power characteristics.Raceway products designed to integratewith PV modules are not readily available.What was the intent behind 690.31(A)?Considering the substantial gap between theCode and the available equipment, how caninstallers comply with this new language?Whenever I give lectures or answerquestions about the NationalElectrical Code, I have a saying in theback of my mind: “There are many waysto interpret the Code—your way, my way,the engineer’s way and the inspector’sway.” It would be nice to add the “correctway” to that saying. The correct wayto interpret the Code, I think, is to fullyunderstand its intent.When that sentence from Article690.31(A) is distilled down to its parts, itbecomes clear that it is concerned aboutdc power conductors in a readily accessiblelocation being accessed or damagedby people or animals and causinga hazard. The main purpose of the NECis the practical safeguarding of personsand property from electrical hazards.One of the ways the Code accomplishesthis is by making electrical circuits notreadily accessible.The NEC definition of readily accessiblereads: “Capable of being reachedquickly for operation, renewal, or inspectionswithout requiring those to whomready access is requisite to climb over orremove obstacles or to resort to portableladders, and so forth.” Inspectors typicallyallow many options for making somethingnot readily accessible. One way isto place a physical barrier between theperson and the object, such as a lockeddoor, a panel cover requiring a tool toopen, a fence, or some other barrierrequiring a tool to remove. Another wayis to elevate the object out of arm’s reach;most inspectors will say that is about 8feet for a person of average height.If dc power conductors are not readilyaccessible, then they do not need tobe enclosed in a raceway. But I’m surethat making the conductors on theback of a ground-mounted array notreadily accessible has installers pullingtheir hair out. Some manufacturersare currently working on solutions thatintegrate the module, the support rackCourtesy meridiansolar.comand associated wiring intoa complete package thatmakes the conductors notreadily accessible.People often argue thattechnology changes happenso fast, the Code can onlyreact to the changes. Thismight be an example of theCode pushing new technologyto conform to the rules.Similarly, there is a proposalfor the 2011 NEC that couldrequire dc arc-fault circuitinterrupter protection on PVsystems. This is new technologythat might not be fullytested and listed, but couldbe required on installationsin the near future.Until more products areintroduced to the market thatconform to the last sentencein Article 690.31(A), theinstaller has several choices to build aCode compliant installation:• Find a module that allows araceway system to enclose theconductors;• Raise the array out of arm’s reach;• Install a barricade around the array;• Install a barricade around theconductors; or• Make the conductors in questionnot readily accessible.That last option might requireinstallers to communicate with theirlocal AHJ to discuss acceptable solutions.After all, the AHJ will be inspectingthe system for Code compliance, socommunication early in the process canalleviate headaches in the final stagesof the installation.—Brian Crise / NECA-IBEW ElectricalTraining Center / Portland, OR / nietc.org18 Solarpro | October/November 2009
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