The LONGBOW™ Cable Ladder is an extra heavy duty, NEMA 20B and 20C system and comprises an all-welded construction, which is made up of two side rails formed to a “C” profile, and perforated cross rungs formed to a "U" channel profile. The use of Structural Grade steel, with certified properties, allows predictable strength characteristics. It warrants the use of thinner steel, hence lighter structures, because of the higher yield and tensile strength. The controlled chemical composition also allows for a more consistent galvanising process.
The LONGBOW™ Cable Ladder is designed to carry a static electrical cable load and the Safe Working Uniform Load (SWL) has been calculated incorporating a 1.5 factor of safety. The Load Chart in the datasheet indicates the performance of the product with the indicated support span. The maximum mid-span deflection ratio would be 1/200 of the span, with an end span deflection of 1/150 of the span. All accessories require support near each end and at the centre. It is recommended that installation is done per the guidelines of NEMA VE 2 – available from www.nema.org.