Parallel Grounds

[Supersparky98]

overcurrent protection

overcurrent protection

why would you use different sizes for phase a , b, and c , it all comes from a 1200 amp overcurrent device and must be sized accordingly

 

[LarryFine]

why would you use different sizes for phase a , b, and c , it all comes from a 1200 amp overcurrent device and must be sized accordingly

There's no good reason to do so, only that it's not mandantory. There's no real danger in one phase having a slightly different impedance than another, but a slight difference in impedance between paralleled conductors can cause one to exceed its ampacity because of non-equal current sharing.

 

[Cold Fusion]

..If you accept that 310.4 requires all the phase conductors to be the same size you must also accept that the EGCs must be the same size because the wording in 310.4 includes 'equipment grounding conductor'.

You're absolutely correct. That's what the 2008 says.

cf