Solar Panel Inspection 101: What to Expect

A completed solar panel installation isn’t the final step in harnessing the sun’s power. There are two parts to a solar panel inspection: the electrical system inspection and the structural inspection. Inspections are required to turn on the system, but you’ll also need them regularly to maintain the warranty and efficiency of the system. As long as your system has been installed correctly, you don’t need to worry about either part of the inspection process, but it can help to know what’s coming. 

Working With Your AHJ

Local solar inspection guidelines vary with the local Authority Having Jurisdiction (AHJ), a government office or entity that regulates safety and building regulations and codes. The AHJ determines whether a government employee or private inspection service can perform the inspection, and some require an electrician to be present.

Work with an experienced local solar panel installer who is familiar with your AHJ. They can offer advice about the permitting process and will know what to expect during inspections. Their experience and advice will also help with practical decisions, such as the direction the solar panels should face.

Electrical System Inspection

The electrical system inspection ensures fire safety, proper installation, and that the correct safety measures are in place. Your inspector will check the materials, location, and distance between electrical components, including the following areas: 

Main Service Panel

At the main service panel, the inspector will check that breakers, wires, and conduits are the correct size or gauge. Both the gauge and type of wire matter for fire safety. Additionally, all electrical connections should be tight and correctly located based on local AHJ guidelines and standards. 

Grounding

Proper grounding diverts fault currents from electrical surges, lightning strikes, or insulation faults. A fault current or short circuit is an unintended or uncontrolled current in the system that can easily cause damage. Inspectors look for a grounding rod and wire and check for the proper materials, such as weatherproof tape at connection points.

AC and DC Switches

The alternating current (AC) and direct current (DC) switches must be within a specific distance of one another and from the electrical meter. These same switches must be accessible to emergency responders in case of a fire or other emergency. 

There also needs to be a disconnect switch for the AC and a disconnect switch for the DC located between the inverter and the utility meter. Some systems have a single switch for both AC and DC, which is a standalone switch or breaker on a service panel.

Labels

Safety labels must be placed on all system parts and features. A placard with the site layout should be placed next to the electrical meter and disconnect switch.

Solar Panel Structural Inspection

Solar panels are installed at a specific distance from the roof and roof edge for fire safety. This part of the inspection will also include examining the panels’ attachment points, mounting rail installation, and fastenings between the panels and the rails. 

Cables shouldn’t dangle or touch the roof.  When deciding if your home was good for solar, you may have reinforced the rafters to support the solar panels. If that’s the case, any rafter reinforcements will also get a once-over, too.