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Figure 6.7. Simple ground mounting for PV arrays using materials readily
                            available from a hardware store (reprinted with permission of Sandia National
                            Laboratories, 1991).

                     It is important to avoid contact between dissimilar materials that could cause
                     damaging electrolysis (Standards Australia, 1999–2000b; Messenger & Ventre,
                     2000). Materials used in mounting structures include:
                         1. Aluminium
                            x  light, strong and resistive to corrosion
                            x  easy to work with
                            x  compatible with most PV module frames
                            x  difficult to weld.
                         2. Angle iron
                            x  easy to work with
                            x  corrodes rapidly if not galvanised and slowly if galvanised
                            x  easily welded.
                         3. Stainless steel
                            x  will last for decades
                            x  expensive and difficult to work with
                            x  difficult to weld
                            x  good for salt spray environments.
                         4. Wood
                            x  cheap, readily available and easy to work with
                            x  needs treatment with preservatives
                            x  not suitable in damp environments.

                     Stainless steel nuts and bolts should be used with all mounting materials.









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