Sizing of neutral conductors

[ettek]

I'm in China inspecting land drilling rigs for inport into the US. I've come accross an issue with 208v distribution from a delta-wye transformer.
The seondary of the xfmer is wye connected/grounded neautral, from there it goes to a lighting distribution panel.
From the lighting distribution panel, "locally manufactured" it goes to other portable buildings.
Between the lighting distriution panels and the other buildings, they are using Chinese manufactured 4 conductor cables and the phase wires are 35mm squared and the 4th (ground conductor) is 16 mm squared.
Since they only had 4 conductors, they took the ground conductor, placed white heat shrink on it and called it Neautral.
My questions are:
1) Where in the NEC will I fid sizing reqirments for a grounded neatral system's neautral conductor?
2) There is not a dedicated gound between the lighting distribution panel and the end panel. What NEC rules does this violate and where can I find them?

Any other input will me most welcome.
Thanks
ettek

 

[jeff43222]

Depending on the version of the NEC you are using, I think the answer to Question 1 can be found in 220.22 of the 2002 NEC, or 220.61 of the 2005 NEC.

For Question 2, there may not be a violation. I'd take a look at Article 250, Parts VI and VII (2005 NEC).