Ground Mounting Solar 101
Not every roof has the ideal sufficient exposure or area to support an array which meets customers electrical needs. Enter the 2 Tier Ground Mount, created for systems from 2 to 200kW. Fast-Rack has designed a universal ground mount that fits both 60 and 72 cell modules. Our unique approach is a modular system, supporting 2 rows of modules and legs sets that be placed up to 10’ apart. Simplified design means the system size can be modified by 2 modules at a time.
HES GMX-2-Tier Features:
Installation of the GMX ground mounts is simple and efficient. The Fast-Rack GMX features include:
• 10’ spacing between feet
• Compatible with screw piles, ballast blocks, piers, beams and other ground connections
• Fits both 60 and 72 cell modules, with frame thickness from 35 to 50mm
• Built-in Levelling features
• All aluminum and stainless steel materials for long term corrosion resistance
• Built-in bonding with Fast-Rack clamps and lugs
Why a Fast-Rack 2-Tier solution? What is special about our mounting system?
Simplified Design. Once you have decided on the number and type of modules to be installed, use our online Fast-Rack GMX Design Tool to determine overall mount size and to print a Material List. Use the results to determine screw piles, or consult our Foundation Guide for ballasted options. (They only need a 1/2" and a 3/4" Socket!)
Flexibility. Our Universal Mounting works with any kind of ground connection. Screw piles are popular if soil conditions permit. Cement ballast blocks are a universal solution for flat ground. For rocky or uneven areas, cement piles or rock bolts, or any structure that creates parallel beams will work. The GMX bolts to anything!
Value. Since our GMX mounts use the same rails as our popular Fast-Rack roof mounts, the value is passed onto installers. All of the hardware parts are universal to the Fast-Rack system, so leftover materials can be used on other projects. Overall our delivered price is significantly better than any of the large scale mount suppliers from the USA.
Ease of Installation. Two people, each with a socket set, can assemble a Fast-Rack GMX mount. First bolt the legs down to the footings/piers/piles, then add the module rails. Install the lower tier of panels first, then the second tier above it. Repeat for each group of 8 panels. Simple and efficient!
Last - Inventory. We stock the materials for GMX mounts in all our warehouses, and can delivery quickly and efficiently to all addresses in Canada. The systems come complete with assembly hardware and are broken down into neat bundles of legs and rails.
What does the Ground Mount mount to?
Each leg of the ground mount must attach to something. That “something” must have the weight or mechanical connection to prevent the whole structure from blowing over in a strong wind.
Popular "somethings" are:
1. Ballast Blocks – Readily available 2000-4000 lb precast blocks from a local concrete suppliers. They are cheap, around $125 per block, and the concrete supplier can crane these into nice neat rows on your site. See our Ballast Fondation Documents.
2. Cement Piers – Conventional concrete post footings can also be poured. These must be deep enough and wide enough to prevent pulling out. You may need to consult a local structural expert to design these for your local soil conditions and wind regime.
3. Screw Piles – Likely there is a local screw pile installer who can drive and install piles in a 7'6"' x 10' grid to match the ground mounts. Again the size and depth reflect local conditions, but the Pile Installer can meet the spec needed for the GM. This option assumes a soil base that you can drive a screw pile into.
4. Rock Bolts/Pins – Rocky areas can use pins drilled or cemented into a solid base. Expansion plugs are an option.
5. Wood or Metal Beams – 2 parallel beams roughly 7’6" apart, attached to the ground with any of the above choices, are easy to connect the mount to. Level and raised off the ground to match local snow depths.
See our Ground Mount design guide for recommendations. But don’t forget that local conditions must be taken into account and sign off by a Professional Engineer may be required.