Here is a question. There is a deck box to a pool. It is the newer style (Intermatic is the manufacture) where you can install 2-3 pipes to the deck box. Each PVC pipe to the deck box has a # 8 cu wire from the wet niche to the proper ground strip inside the deck box. It also has the required #12 CU ground wire back to the pool control box. The deck box is installed properly. ( Height of ground, distance from pool, etc.)
This particular deck box happens to have an external bonding lug. The manufacture instruction state, "The external grounding lug is provide in case your installation requires it."
Now the question, if everything is wired properly, as per the 2005 or 2008 NEC, would you need to use that bonding lug? When would that external ground lug be needed? Should there be a # 8 CU bond wire back to the pool control box? Should that external ground lug need to be connected to the bonding grid? Should nothing be hooked to that external lug?
That is what I did with mine although the #8 stranded from the niche (2 in my case) is also part of the 680.26 grid. It was just easy because I had the #8 solid going right by the J box on the way to the pump, heater pad. I figure the more bonding the better in a pool.
I can't think of anything that is required to be connected to that lug. You need the hot, neutral and insulated EGC from the line side, the hot, neutral and EGC to the light via the cord and the #8 bonding conductor from the niche. The niche also gets bonded to pool steel. These days the niche is usually plastic so all you are really bonding is the speed nut that the light screws into
At first I thought that you should bond to that lug, but the more I think about it and ask others, the more I guess that it does not have to be bonded to anything. I guess you could use that lug and bond to a fence if you were close enough to the fence.
Normally the contractor wouldn't have a problem coming back to throw a bond wire to the deck box. In this case the contractor is an hour away from the job. As long as the job is safe and meets code and manufactures instructions, then I would be OK with it.