SolispecStart
UAPLDEES

Solar panel ground truss check to DBN

Enter the region, tilt, panels per row, the panel, the profile and the supports — the calculator checks the truss with the same calculation as the Solispec designer: snow and wind to DBN V.1.2-2:2006 with Amendments 1 and 2, the C profile to DSTU-N B EN 1993-1-3:2012, the tube to DBN V.2.6-198:2014. You see how loaded the rail, rafter, posts and node are, which is the weakest and how to fix it.

A truss for solar panels is designed for your region’s snow and wind to DBN V.1.2-2:2006. The most loaded parts are usually the rafter — the rails bear on it between the nodes — and the rail between the trusses. A shorter truss spacing (fewer panels on a row’s six trusses), a thicker wall or a tube instead of a C profile add margin. A perforated profile is fixed with one bolt through the factory slot, without drilling.

How it is calculated

The truss is a plane frame: the rafter is continuous, the posts and the base are pinned, the front support is a pin and the rear one a roller. The rails do not sit at the nodes, so the rafter also works in bending. Loads to DBN V.1.2-2:2006 with Amendments 1 (2007) and 2 (2020): the regional centre’s snow S₀ and wind W₀ (Annex E), μ per Annex Zh, wind with C_h from Table 9.01, the canopy force coefficient c_f from EN 1991-1-4 Table 7.6 as clause 9.8 allows; combinations per 4.18; T = 50 years, γ_n = 1.0, terrain type II. The C profile to DSTU-N B EN 1993-1-3:2012 (effective section, stability), a perforated one with the net section through the slot; the tube to DBN V.2.6-198:2014. The rail is a continuous beam over six trusses: strength and deflection L/200 (an assumed limit). A perforated profile’s node is one M10 bolt through the factory slot: the node force is compared with the reference bearing resistance of a bolt in a round hole (EN 1993-1-3 Table 8.4); for a slot the final data come from the profile maker. The tube node is not checked. Steel weight is the cut lengths of one row’s trusses, rails and braces.

The calculation is preliminary. A qualified engineer must check it before installation. Codes: DBN V.1.2-2:2006 (Ukraine) and the Eurocode; for other countries — snow and wind values from the national annex, entered by hand.

Frequently asked questions

What tube or profile does a solar panel truss need?

It depends on your region’s snow and wind, the tilt and the truss spacing. For a row of five portrait panels 2350×1100 on six trusses in Kyiv, both the perforated C profile 41×41×2 and the tube 42×42×2 pass. Enter your own values in the calculator above.

What truss spacing do solar panels need?

A row has six trusses, so the row length sets the spacing: about 1,040 mm for five portrait panels 1,100 mm wide. The more panels in a row, the larger the spacing and the load on the rail and rafter; the designer flags a spacing over 2,000 mm.

Do I need to drill a perforated profile?

No: at a truss node one M10 bolt goes through the factory slots of both profiles, back to back, and no profile passes through another. The calculator checks that every node bolt lands in a slot at your tilt and, if not, suggests the nearest tilt at which they do.

Can I build from this calculation?

It is a preliminary calculation. A qualified engineer must check it before installation. For the same inputs the Solispec designer gives the full report: member forces, drawings, cutting list and bill of materials.

Ground frame designer

Design the ground frame for your solar plant

The calculator’s values go to the designer: then the frame, the DBN checks and the estimate.

Design the frameAll calculators