CSLB C-46 Solar ContractorElectrical and Plumbing CodesMedium
A solar contractor is installing a grid-tied PV system on a commercial building. The system includes multiple string inverters that are connected to a common AC combiner panel. The local utility requires a visible, lockable, and readily accessible AC disconnecting means for the PV system. According to NEC Article 690.15, where must this AC disconnecting means be located?
- AAdjacent to the utility's point of connection to the building.
- BWithin the AC combiner panel, but only accessible by qualified personnel.
- CAt the inverter location, within sight of and readily accessible to the inverter.
- DAt a readily accessible location on the exterior of the building, or within sight of the service entrance equipment.
Show answer & explanationAnswer & explanation
Correct answer: D. At a readily accessible location on the exterior of the building, or within sight of the service entrance equipment.
NEC Article 690.15(A) states that the AC disconnecting means must be installed at a readily accessible location on the exterior of the building or within sight of the service entrance equipment. This allows emergency personnel or utility workers to quickly de-energize the PV system.
Why the other options are wrong
- A. While often near the utility connection, the primary NEC requirement is about accessibility and visibility for emergency services/utility, not strictly adjacent.
- B. The disconnect must be readily accessible to ALL, not just qualified personnel, and must be visible.
- C. This describes the DC disconnecting means location, not the main AC disconnect for the system.
PV AC Disconnect Location
The main AC disconnecting means for a PV system must be readily accessible on the building exterior or within sight of the service entrance equipment, per NEC 690.15(A).
- Crucial for emergency shutdown.
- Must be visible and lockable.
- Ensures safety for first responders and utility workers.
Memory trick: AC Disconnect: Outside or Eye-Level with Service.