Nov 2023


PV Module Insufficient Safety Distance

The IEC 61730 standard provides requirements on a minimum distance between the active parts of the module (i.e. the connectors inside the laminate). This dimension is called the “creepage distance”. 

This month we highlight non-conformities discovered when verifying this creepage distance, which was smaller than instructed by the standard. A reduced creepage distance in PV modules can have various adverse consequences, including safety hazards, reduced efficiency, potential for damage, and compliance issues. It is essential to adhere to required safety guidelines and standards when designing, installing, and maintaining PV systems.

A root cause analysis revealed that this non-conformity has been caused by a too-large spacing between cells. During the module’s rework process, employees omitted to inspect the spacing between the strings when lifting and then placing the string back down, resulting in an increased string spacing and causing a smaller creepage distance at the edge of the module. 

STS inspectors are your boots on the ground to identify these issues. This non-conformity may be identified during production monitoring or during random final inspection.