Next size fuse breaker

[mannyb]

Set of parallel 500mcm aluminum wire rated at 310a is good for 620amps can the next size fuse is 800a. Could this be possible or not?

 

[petersonra]

No because the next rating up is 700 Amps

 

[infinity]

As Bob stated the rule requires you to go up to the next standard size from Table 240.6(A).

 

[mannyb]

I'm only asking because some how some way it passed inspection. My guess is that they switched fused during inspection from 800a to 600a then switched back once final passed Or inspector wasn't paying attention. Just trying to.figure out how they did it.

 

[infinity]

My guess is that they switched fused during inspection from 800a to 600a then switched back once final passed Or inspector wasn't paying attention.

Anything is possible. Unless the calculated load was between 601 and 620 amps I would use 600 amp fuses.

 

[Knightryder12]

What are these feeding? Is it service conductors or is it feeding a motor load?

 

[Tulsa Electrician]

By chance could be an adjustable circuit breaker and turned down.

Are both sets in the same raceway. Just curious

As mentioned above by chance utility installed

 

[mannyb]

What are these feeding? Is it service conductors or is it feeding a motor load?

Service conductors

 

[Knightryder12]

Service conductors

As others have stated, 700 amp breaker is the next size up.