AS/NZS Earthing Solar
The earthing approach for a solar array changes depending on whether it is mounted on a roof or on the ground.
A roof-mounted array and a ground-mounted array both need proper earthing, but the practical considerations differ meaningfully between the two configurations.
Panel frames bond to the mounting rail, which bonds back to the building's main earthing system — typically a relatively short bonding path back to an earthing reference that's already well-established for the rest of the building.
A ground-mounted array sits physically separate from the building, often at some distance, which usually calls for its own dedicated earth electrode near the array itself — bonded back to the main earthing system, but not solely reliant on a long bonding run back to the building's earth reference.
| Consideration | Roof-mount | Ground-mount |
|---|---|---|
| Bonding path length | Short — mounting rail to nearby building earth bar | Potentially long — may need a local electrode instead |
| Local earth electrode | Rarely needed independently | Often needed or beneficial near the array itself |
| Exposure to mechanical damage | Lower — elevated, less accessible | Higher — ground-level bonding conductors more exposed |
Work through the earthing requirements for your specific configuration in the AS/NZS Earthing calculator.
Engr. Jason Morales — Founder, SolarEnergyPH & OhmWorks