English to Russian Tech/Engineering Electronics / Elect Eng

when cable ladder is to be installed on long spans of 5 metres or 6 metres the limiting factor which determines
the loading capacity is the maximum allowable stress in the ladder side rails rather than the deflection. Deeper side rails can withstand higher stresses and for this reason 125mm deep Sapphire or, better still, 150mm deep Emerald ladder should be used for long spans. The shallower Topaz and Opal ladders are not suitable. The maximum Safe Working Loads for 5 metre or 6 metre spans given in table 9 actually result in mid-span deflections of about 1/400th of the span only.

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