In conjunction with connectors, particularly when cable trays of greater than 200mm are used. It is always recommended to use fish plates In an installation they will require extra local support. When accessories (bends, tees, risers etc.) are involved Only straight length beams are discussed above. Loading condition it can be taken that the permissible load is reduced to 0.5 that shown for intermediate span in multi-span beams.Ĥ. If a loading condition occurs where there is only a single span The diagram shows a typical multi-span beam loading condition.
These are positions of maximum bending moment.ģ. The installer should avoid placing connections in To locate connections between component lengths of cable tray/ladder. Bending moment is zero at approximately 0.25L either side of the intermediate supports.
#Expansion connector for cable tray full
If an installation requires full load carrying capacity along the whole length, than full capacity of the intermediate spans can be used if the end spans are reduced to 0.75L (length of intermediate spans).Ģ. Bending moment is much larger in the end spans of the continuous beam than the intermediate spans which will reduce the load carrying capacity in the end spans. A typical bending moment diagram shown on the previous page shows the following:ġ. Normally cable tray / ladder is connected together forming a continuous beam over several supports. Increasing the span (horizontal distance between supports) will always reduce safe load carrying capacity and increase deflection. A properly specified system will ensure that the stress does not exceed to that which is safe for the materials used in the components.Ī suitable installation will require choice of appropriate style of tray / ladder and the location of supports. Stress will be induced and deflections (vertical displacements) will be observed. The loads imposed and the type and location of supports will create a pattern of bending moment in the structure. If components are incorporated in an exterior installation there may be other loading factors to consider, such as wind, ice and snow.Ĭable tray & ladder acts as a structural load carrying beam when installed horizontally. If a point load is applied to the tray / ladder it will potentially have a significant effect and this must be quantified.Ģ.
The capacity charts provided in this catalogue assume that loading is uniform, both along length and across width.
However, it is alwaysĪdvisable to consider that future system requirements can be expected and allow 20% for additions at a later date.ġ. The weight of cables to be fixed on the system will provide the basic loading data.
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