PaulHartley
Member
- Location
- United States
For a PV Array where multiple source circuits feed into a Transition Box, and then from there multiple conduits feed these source circuits directly to multiple inverters...
PER NEC '11, Does each conduit (EMT) have to have it's own EGC, or can a single EGC wire run from the equipment grounding point in the Transition Box through one of the conduits to one of the Inverters (and on to the AC combiner)?
Each inverter output would have its own EGC that connects the inverter to the ground in the AC combiner. All the conduits would have grounding bushings at both ends. But each conduit from rooftop Transition Box to Inverter would not have its own separate EGC (this is the main question...whether this is allowed per the NEC?)
Section 250.134 (B), Exception No. 2, allows the DC EGC to not run with the circuit conductors, which seems to speak to this question, but I'm not sure of this is the correct interpretation.
Thank you for any insights.
Paul Hartley
PER NEC '11, Does each conduit (EMT) have to have it's own EGC, or can a single EGC wire run from the equipment grounding point in the Transition Box through one of the conduits to one of the Inverters (and on to the AC combiner)?
Each inverter output would have its own EGC that connects the inverter to the ground in the AC combiner. All the conduits would have grounding bushings at both ends. But each conduit from rooftop Transition Box to Inverter would not have its own separate EGC (this is the main question...whether this is allowed per the NEC?)
Section 250.134 (B), Exception No. 2, allows the DC EGC to not run with the circuit conductors, which seems to speak to this question, but I'm not sure of this is the correct interpretation.
Thank you for any insights.
Paul Hartley