Is there an industry standard that states what the allowable deflection on a cable tray is supposed to be? I found a product catalog that says a "guideline" is L/200. Is there any standard/code that specifies it?
I don't believe their is a specification or standard, but deflection of L/200 is typical for cable tray manufacturer's products. In the USA, OSHA acknowledges and accepts the L/200 criteria as good practice for a fully loaded cable tray. See page 4 of OSHA's "Safely Installing, Maintaining and Inspecting Cable Trays":