Sparx, you are correct: I am from the states and now realize I should move my question over to another site. Anyway, many thanks to you and Eric for answering.
I recently moved my hot tub that was built into my deck to replace the decking and put on a new roof. I moved the hot tub about 20 feet away from the prior location. The hot tub is a free standing tub and runs on 220v (50amp). Previously, the GFCI box was 5-6 feet away and is located on the exterior...