What is UL 60335-2-96?

UL 60335-2-96 is a safety standard developed by Underwriters Laboratories (UL) for household and similar electrical appliances. This standard specifically addresses the safety requirements for solar photovoltaic (PV) power systems, including modules, inverters, and associated components. The purpose of UL 60335-2-96 is to ensure that these systems are safe to use and operate, and to mitigate any potential hazards that may arise from their installation or usage.

Mandatory Testing Procedures

Under UL 60335-2-96, manufacturers of solar PV power systems must conform to specific testing procedures in order to obtain certification. These procedures involve conducting various tests to assess the safety and performance of the system. Some of the key tests include insulation resistance testing, ground continuity testing, thermal cycling testing, and temperature rise testing.

Insulation Resistance Testing

Insulation resistance testing is an essential part of the certification process under UL 60335-2-96. This test determines the ability of the system's insulation materials to withstand electrical stresses and prevent current leakage. The test involves applying a voltage to the insulation and measuring the resistance. If the measured resistance falls within the specified limits, the system passes the test; otherwise, further investigation and improvements are required.

Thermal Cycling Testing and Temperature Rise Testing

Thermal cycling testing and temperature rise testing are conducted to evaluate the thermal performance of the system. Thermal cycling testing involves subjecting the system to alternating hot and cold temperatures to simulate real-world conditions. Temperature rise testing measures the increase in temperature when the system is operated at full load for a specific period. These tests help ensure that the system remains within safe temperature limits and can operate effectively without any risk of overheating or fire hazards.

In conclusion, UL 60335-2-96 is a vital safety standard for solar PV power systems. It sets forth comprehensive testing procedures to ensure the safe installation and operation of these systems. By conforming to the requirements of this standard, manufacturers can demonstrate the reliability and adherence to necessary safety measures, thereby instilling confidence in consumers and promoting the wider adoption of solar energy.