Cable trays are not connected with jumpers
Standard splice plates can often provide a safe electrical path if they are UL Classified and bolted tight. However, you must use copper bonding jumpers if the tray is painted or has expansion joints for movement. It is not necessary to install bonding jumpers in parallel with the standard rigid aluminum or steel one-piece metallic bolted side rail splice plates that are the connections between the cable tray sections. Cable tray installation may seem straightforward, but field experience reveals the same five defects appearing repeatedly across projects worldwide.
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