What type of overcurrent devices should be used in PV source circuits?

The correct choice of using listed devices specifically for PV systems is important due to the unique characteristics and requirements of photovoltaic (PV) systems. Overcurrent devices used in PV source circuits must be designed to handle the specific operational and environmental conditions that PV systems often face.

Listed devices for PV applications have been tested and verified to operate reliably under the conditions expected in solar energy environments, such as exposure to extreme temperatures, elevated humidity, and potential exposure to sunlight. They are also designed to break DC currents, which behave differently than AC currents, particularly in how they can create an arc during a fault condition. These devices ensure safety and compliance with the National Electrical Code (NEC), specifically in regards to both performance and installation requirements.

In contrast, options like generic overcurrent devices or standard circuit breakers may not meet the specialized needs of PV systems due to the differences in operational dynamics of DC circuits. Additionally, high-voltage rated devices, while they may handle higher voltages, might not be specifically designed for the safety and operational characteristics that PV systems require. The use of devices specifically listed for PV applications ensures reliability, safety, and adherence to industry standards.