Carultch
Senior Member
- Location
- Massachusetts
As the title says, what is the difference between a full 100% rated breaker and its standard rated counterpart?
Example: how does an 80A/100% breaker compare to an otherwise equivalent 100A standard 80% rated breaker? I take it that this isn't just a re-labeling of the same device, otherwise it wouldn't make sense for the 100% rating standard to exist. Although at first glance, it might appear this way.
I understand the sizing algorithm for selecting the breaker, but how does this affect the rest of the design, such as circuit ampacity? Using a 100A standard rated breaker, one would need greater than 90.1A worth of wiring to be compliant (presuiming all other rules also comply). But do you still need 90.1A worth of wiring to be compliant with an 80A/100% rated breaker? Or is it 70.1A worth of wiring?
If you are wondering where I'm getting 90.1A and 70.1A, this is from 240.4(B), the "next size up" rule. And like I said, assume that all other rules also comply.
Example: how does an 80A/100% breaker compare to an otherwise equivalent 100A standard 80% rated breaker? I take it that this isn't just a re-labeling of the same device, otherwise it wouldn't make sense for the 100% rating standard to exist. Although at first glance, it might appear this way.
I understand the sizing algorithm for selecting the breaker, but how does this affect the rest of the design, such as circuit ampacity? Using a 100A standard rated breaker, one would need greater than 90.1A worth of wiring to be compliant (presuiming all other rules also comply). But do you still need 90.1A worth of wiring to be compliant with an 80A/100% rated breaker? Or is it 70.1A worth of wiring?
If you are wondering where I'm getting 90.1A and 70.1A, this is from 240.4(B), the "next size up" rule. And like I said, assume that all other rules also comply.