CSLB C-46 Solar ContractorElectrical and Plumbing CodesEasy
A solar installer is commissioning a new PV system. The homeowner asks about the purpose of the readily accessible, lockable, and labeled PV system disconnecting means. Which of the following best describes its primary function according to the National Electrical Code (NEC)?
- ATo prevent unauthorized access to the PV system's internal components.
- BTo isolate the PV system from other electrical loads during maintenance or emergencies.
- CTo allow the homeowner to easily turn off the system for energy savings.
- DTo provide a convenient point for utility companies to monitor system performance.
Show answer & explanationAnswer & explanation
Correct answer: B. To isolate the PV system from other electrical loads during maintenance or emergencies.
The primary function of the PV system disconnecting means, as required by NEC, is to provide a safe method for isolating the PV system from other electrical loads and the utility grid. This is crucial for safety during maintenance, repair, or emergency situations, allowing first responders or technicians to de-energize the system.
Why the other options are wrong
- A. While lockable, its primary function is isolation for safety, not just preventing unauthorized access.
- C. While it can be used for this, energy savings is not its primary safety-driven purpose.
- D. Utility companies typically use metering equipment for monitoring, not the main disconnect for this purpose.
PV Disconnecting Means Purpose
The main safety function of a readily accessible, lockable, and labeled PV system disconnecting means, as required by the NEC.
- Provides a way to de-energize the PV system.
- Crucial for safety during maintenance or emergencies.
- Must be readily accessible, lockable, and labeled.
Memory trick: The PV disconnect is the safety stop, for workers to maintain or for emergencies to drop.