Voltage Testing: After verifying that the power is off, use a multimeter to check for any voltage leakage in the junction box. This involves checking the wires relative to the ground. IEC 62790 Junction Box and Cable Testing for PV Modules: Ensuring Safety and Efficiency The solar industry has witnessed unprecedented growth in recent years, driven by increasing demand for renewable energy sources. As the world transitions towards a more sustainable future, manufacturers of. This content provides you with a sample junction box inspection and test plan. You need to modify this junction box ITP to meet your specifications. Junction Box Ancillary items (Bolt, Nut, TERMINALS, ETC.