RexRack Mounting

RexRack™ Commercial-Grade Mounting Hardware

With the introduction of RexRack, SunEarth has made significant strides in the area of standardized mounting hardware for commercial applications.

RexRack represents a grounds-up engineered approach to the design and construction of commercial racks. Gone are the days of custom fabricating racks for each application on site.

RexRack is a completely modular system with telescoping front and rear legs to accommodate uneven roof surfaces, and to provide a range of slope adjustment for the array.

Whereas most custom racks are made from steel and pressure treated lumber that can rust and dry rot, RexRack components are made from anodized 6063-T6 structural Aluminum and 316 Stainless Steel.

One aspect that differentiates the RexRack package from traditional mounting systems is that there are no runners on the roof surface. In the RexRack system, the runners are fabricated from our SolarStrut material and are located on the underside of the collectors.

By relocating the runners to the backside of the collectors, a reinforced lattice is created between the two strut runners and the collectors that are clamped to them. The array itself becomes a single unified rigid body, much like unibody construction in newer automobiles. When the array itself is rigid, the rear legs need only carry the vertical load of the array, which means that less extensive cross-bracing for lateral loads is required.

Flush Mount Front Foot (MTG-FF)

The flush mount front foot is the simplest manner of anchoring the toe of the array and consists of the strut hinge piece pivoted inside 2x2" channel. This front foot may be used when only an inch or two of clearance is required between the collectors and roof or mounting surface. These feet may be appropriate when multiple collectors are installed on a residential roof, or when the array is installed on top of pre-existing runners.

10-16" Front Telescoping Front Foot (Little Foot)

The 10-16" front telescoping foot consists of a 3/16" thick 5052 aluminum gusseted base with holes that allow for 1/2" bolts for securing the base to the roof. A section of Solar Strut is then TIG welded to the base as a standoff and a custom extruded telescoping section is inserted into the strut base to provide height adjustability between 10 and 16". The swivel hinge for the strut runners under the array is attached to the top telescoping section with a 5/16" stainless bolt and hardware. Once the front feet have been adjusted across the rack to accommodate the unevenness of the roof surface, their height is fixed by driving a tek screw through the outer strut section and inner slider on all three sides. At full extension there will always be several inches of slider inserted into the strut base for a combined support thickness of 1/4" to bear the weight of the array!

10-16" Front Telescoping Foot (Big Foot)

The 'Big Foot' is similar to it's smaller sibling but simply includes a 6" square base plate that provides increased lateral support and two additional attachment points. The 'Big Foot is created by TIG welding a 3/16" base onto the 'Little Foot' for a combined base thickness of 3/8" under the center channel.. Four holes are located at the corners of the base to accept up to 1/2" bolts for securing it to the roof.

Telescoping Rear Legs

Telescoping rear legs consist of the same strut and slider assembly as the telescoping front feet except they are hinged inside a 2x2" channel instead of welded to a pad base. Rear legs are available in three ranges specified by their minimum compacted length and maximum allowable extended length

Part No
Part No	Minimum Length (in)	Maximum Length (in)
MTG-RTL-2441	24	41
MTG-RTL-3865	38	65
MTG-RTL-5897	58	97

Sizing Charts for RexRack

For each combination of front feet and rear legs, there is a range of slopes possible for the array depending on the extension of the rear legs and the collector used. The tables on the right are calculated with the assumption that the rear strut runner is set in 25% from the end of the collectors per our recommendations.

3x8' and 4x8' Collectors

Front Foot

Rear Leg

MTG-RTL-2441

MTG-RTL-3865
MTG-RTL-5897

MTG-FF
18-30°
28-42°
39-53°

MTG-FTF-1016-LF
6-19°
17-33°
29-46°

MTG-FTF-1016-BF
6-19°
17-33°
29-46°

4x10' Collectors

Front Foot

Rear Leg

MTG-RTL-2441

MTG-RTL-3865
MTG-RTL-5897

MTG-FF
15-25°
23-36°
33-47°

MTG-FTF-1016-LF
5-15°
13-28°
24-40°

MTG-FTF-1016-BF
5-15°
13-28°
24-40°