690.31(C)(2) Cable Tray.
Code Change Summary: A new section now allows cable trays to be used in outdoor locations for specific PV source and PV output circuits.
The 2014 NEC® now allows type PV wire, with or without a cable tray marking or rating, installed as PV source or PV output circuits, to be installed in outdoor cable trays as long as the cables are supported at no more than 12 in. intervals and secured at 4.5 ft. intervals.
In order to properly apply this code section, it is important to recognize which conductors are the PV source and PV output circuits:
- PV source circuits are run between modules and from modules to the common connection point(s) of the dc system. The common connection point is usually the inverter or possibly a combiner box where the source circuits combine in parallel to become a PV output circuit.
- PV output circuits are the circuit conductors between the PV source circuit(s) and the inverter or dc utilization equipment.
This new code section does not mention PV conductors on the AC output side of the inverter which is the inverter output circuit.
Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on the “free access” tab and select the applicable year of NFPA 70 (National Electrical code).
2014 Code Language:
690.31(C)(2) Cable Tray. PV source circuits and PV output circuits using single-conductor cable listed and labeled as photovoltaic (PV) wire of all sizes, with or without a cable tray marking/rating, shall be permitted in cable trays installed in outdoor locations, provided that the cables are supported at intervals not to exceed 300 mm (12 in.) and secured at intervals not to exceed 1.4 m (4.5 ft).