NEC 690.12 and Fire Safety: What Are the Guidelines?

NEC 690.12 outlines specific requirements for rapid shutdown systems in solar electric power systems. These guidelines aim to reduce the risk of electrical shock and fire hazards when a worker is accessing the solar array. Rapid shutdown systems must disconnect power to the array within 30 seconds.

NEC 690.12 Rapid Shutdown Requirements

The National Electric Code (NEC) requires that solar rapid shutdown systems disconnect power to the array within 30 seconds when a worker is accessing the array. This ensures that the risk of electrical shock and fire hazards is minimized. The shutdown system must be capable of disconnecting all conductors in a single array string within 30 seconds.

Testing Rapid Shutdown Systems

To verify compliance with NEC 690.12, rapid shutdown systems must be tested according to the manufacturer’s instructions. Testing typically involves connecting the shutdown system to a simulated array string and verifying that the system can disconnect power within the 30-second time frame. It is essential to use a suitable test setup that accurately represents the conditions found in a real-world solar array.

Installation Considerations

When installing a rapid shutdown system, it is crucial to follow the manufacturer’s instructions and local electrical codes. The shutdown system must be installed in a location that is accessible and clearly marked for workers. Additionally, the system must be connected to the solar array and the inverter in accordance with the manufacturer’s instructions. This ensures that the rapid shutdown system functions correctly and provides the required level of safety.