Re: Bonding of conductor to a Cable tray
My take on this is that it probably does not matter much if you bond them together or not. if lightning hits the roof of your building, it is just as likely to jump to the cable tray regardless of whether it is bonded or not to the air electrode downwire or not.
It would appear from this FPN, that you may have to bond them. I think you would need to consult the referenced std.
250.106 FPN No. 2: Metal raceways, enclosures, frames, and other non?current-carrying metal parts of electric equipment installed on a building equipped with a lightning protection system may require bonding or spacing from the lightning protection conductors in accordance with NFPA 780-1997, Standard for the Installation of Lightning Protection Systems. Separation from lightning protection conductors is typically 1.8 m (6 ft) through air or 900 mm (3 ft) through dense materials such as concrete, brick, or wood.
