Feeder cable size

[codequestion]

What would be typical incoming feeder cable size be for 800 amp service disconnect?

Sent from my SM-G935U using Tapatalk

 

[infinity]

How many sets? Do you have access to Table 310.15(B)(16)?

 

[codequestion]

Wouldnt sets depend on lot of factors? What does contractor use typically? Need to size GEC and main bonding jumper.

How many sets? Do you have access to Table 310.15(B)(16)?

Sent from my SM-G935U using Tapatalk

 

[electrofelon]

4 sets of 250 AL or 4 sets of 3/0 CU. Some people might do it with 2 or 3 sets also.

 

[infinity]

2 sets of 500 kcmil, calculated load less than 760 amps. 2 sets of 600 kcmil, calculated load above 760.

 

[electrofelon]

What would be typical incoming feeder cable size be for 800 amp service disconnect?

Sent from my SM-G935U using Tapatalk

In summary, it depends on a few things. First, what exactly you mean by "800 amp". Next size up rule and 2-6 rule may allow conductors to be sized by the load not the equipment rating. Second, copper vs AL. Third, installer preference. For example I am a one may operation so I prefer more smaller sets. I did an 800 amp once with two sets of 750 AL, but that was because the utility had an odd requirement that I could only have two sets. Normally I would have perhaps done 3 350AL or 4 250AL - probably the 3 350 (if i didnt need the full 800).

 

[augie47]

Unless the GEC is exceptionally long I wouldn't fret over it. If you follow infinity's advice the jumpers/GEC would be 3/0 at worse and 2/0 in best case scenario. Use the 3/0 and move on.