I started this because many are unaware that corner grounded systems are even being installed. The color coding came up because I have seen every varity of colors starting with the basic colors for three phase and then deciding which color to not use, i.e. 480 V brown, orange, yellow. Which color do you drop ? Do you use grey for the grounded and hope the next guy knows what he is looking at ? I would always do a simple line drawing of a delta with the ground off the corner inside the disconnect and trust that whoever had the equipment open would recognise it.
I had one utility guy insist on red with a wrap of green with the brown & yellow to flag it for line crews that might come into the area from other regions in case of major outages.
A good understanding of corner grounded systems is as important as an understanding of a 4 wire, high leg 3 phase. Not knowing can cause injury and damage to equipment.
I hope that some may have benefited from this post.
