[BC] AC Voltage Drop

[Danny Ray Boyer]

To the NEC guru's on the list -

Can anyone direct me to the paragraph(s) in the NEC handbook which 
reflects what kind of voltage drop is permissible from an electrical 
provider from no load to full load.  This is for a a 240 volt - 3 phase 
Open Delta AC circuit. 

The power transformers on the pole are within 150 feet of the load.  The 
3 conductor wire (and neutral) between the ransformers on the pole and 
the fused disconnect panel are sized for 200 amp. 

Danny Ray Boyer