bullheimer
Senior Member
- Location
- WA
I Might not be giving all the numbers here because my brain already aches from doing it at the parts counter but i have a pole mounted meter with one riser that i wish i could use anything other than 4/0 copper but cant because i need it to handle the service of 200A (so a 83% thats 166A), but i am restricted to a 2.5 inch riser! therefor had to use copper. and since i have 4 count'em four, conductors, that means i have to de rate to 80%!!
so that is only 160A, so i am not able to use 4/0 AL because of that, same for the 3/0 CU! because it's only 200A. and the 4/0 AL was only 180A anyway. the 3/0 was close but no cigar, while the 4/0 is something like 425 i forget.
long story short, the insulation on the URD we usually use is RHH-2 and that is the same as RHH in the conduit fill chart, so i have to use copper both for size and ampacity. is there anyway anybody can see around having to use 4/0 Copper in this riser for a 200A resi service? i don't see it happening. i am stuck with 2.5 inch pipe because my meter is sandwiched into a space only 9" wide or i could use 250mcm i think. but i didn't do any calcs with that because the pipe size eliminated that from the equation. so i'm planning on getting 4 4/0s and one 2/0 for the nute, which doesnt have to go up and down.
ps if you plan to do the calcs it might take more time than you want to spend. i know my friend here has passed with using 4/0 URD but i have an inspector up my butt and don't think 4/0AL is kosher.
so that is only 160A, so i am not able to use 4/0 AL because of that, same for the 3/0 CU! because it's only 200A. and the 4/0 AL was only 180A anyway. the 3/0 was close but no cigar, while the 4/0 is something like 425 i forget.
long story short, the insulation on the URD we usually use is RHH-2 and that is the same as RHH in the conduit fill chart, so i have to use copper both for size and ampacity. is there anyway anybody can see around having to use 4/0 Copper in this riser for a 200A resi service? i don't see it happening. i am stuck with 2.5 inch pipe because my meter is sandwiched into a space only 9" wide or i could use 250mcm i think. but i didn't do any calcs with that because the pipe size eliminated that from the equation. so i'm planning on getting 4 4/0s and one 2/0 for the nute, which doesnt have to go up and down.
ps if you plan to do the calcs it might take more time than you want to spend. i know my friend here has passed with using 4/0 URD but i have an inspector up my butt and don't think 4/0AL is kosher.
