PatCBO
Member
- Location
- yuma, az, USA
We stumbled across a little different scenario for the location of a de-rating of a main OCD. Scenario: new pv system installed on a manufactured home with a maximum current output of 47 ampere; Interactive inverter output circuit landing on the 200 ampere panel bus bar located in the manufactured home (110ampere calculated load); the manufactured home panel is fed from a 200 ampere service pedestal on the lot which includes 3 additional OCD for swimming pool, 30ampere/120volt RV outlet and a convenience outlet.
The installing contractor is indicating a 175 ampere main OCD for the manufactured home panel is no longer available and wants to de-rate the main OCD in the pedestal to 175 ampere. From all I have read and researched in the NEC, the bus bar rating where the PV circuits are landing must meet the 120% rule to protect the bus bar. The PV circuits could be landed on the pedestal bus bar, however the contractor is wanting to avoid trenching.
In reviewing 705.12(B)(2) the only other option I see available is (c) unless the panel OCD is reduced to 175 ampere; or does changing the main OCD in the pedestal meet the intent of the code?
appreciate you comments!
The installing contractor is indicating a 175 ampere main OCD for the manufactured home panel is no longer available and wants to de-rate the main OCD in the pedestal to 175 ampere. From all I have read and researched in the NEC, the bus bar rating where the PV circuits are landing must meet the 120% rule to protect the bus bar. The PV circuits could be landed on the pedestal bus bar, however the contractor is wanting to avoid trenching.
In reviewing 705.12(B)(2) the only other option I see available is (c) unless the panel OCD is reduced to 175 ampere; or does changing the main OCD in the pedestal meet the intent of the code?
appreciate you comments!