Mike Dolt Enterprises
Mike Dolt Enterprises
User: bth0mas20, Location: Maryland
Asked on: Wednesday, March 30, 2011 at 9:16 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:31 am EDT
Question: I dont get these jobs often enough to keep up with the codes. I got a call today to replace 150' of 4/0 copper wire from a meter to the 200amp panel in a resturant.Its 3 phase and the inspector said that the 4/0 needs to be removed and 2/0 pulled in place of it. I looked in the code book and saw that 2/0 copper is good for 195 amps 90 deg C. With the run being 150' and its only good for 195 amps is this allowed? I cant replace the pipe because its already in the floor.
According to Table 310.15(B)(16), 2/0 copper wire is rated for 195 amps at 90°C for a 3-phase, 4-wire service. However, since the run is 150 feet, the ampacity of the wire must be adjusted for the increased length.Using Table 310.15(B)(16), the ampacity of 2/0 copper wire at 90°C for a 150-foot run is 165 amps. This is less than the required ampacity of 195 amps for a 200-amp service.Therefore, 2/0 copper wire is not allowed for this application and 4/0 copper wire must be used. Flag for review