Square D I-Line breaker to Cutler Hammer main lugs

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AndyB

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I recently failed an inspection for the following.

Switch gear is Square D I-line, I installed a 200amp 208v breaker to feed a sub panel two suites over using a Cutler Hammer 200 amp 208v panel board with main lugs.

Inspector failed the install and cited the ISC ratings between Square D and cutler hammer wasn't the same and that I needed to install a sub panel with a main breaker to correct the violation. He didn't cite any specific code but I'm guessing he is referring to a UL listing.

Is he correct in calling the violation?
 
I vote "possibly" and "no".
If "series ratings" were used to satisfy the available fault current, then using a different manufacturer of breaker would be a violation as there is no listing for series-rating by crossing brands. If the C-H breakers are fully rated at or above the AIC then no violation. (If you have 200 amp branch breakers, my money would be on a violation but there are so many variables).
As far as a main breaker at the panel, IMHO, no violation (408.36)
 
I don't recognize the phrase "ISC rating between" breakers.

I can go along with Gus, and assume the inspector is talking about the breakers being in series. As long as the AIC of an individual breaker is fully rated for the fault current available at its line side terminals, it may be used regardless of any upstream device.
 
Pierre C Belarge said:
What is the available fault current at the gear?
What is the rating of the panel you installed?
What is the length of the conductors you installed?
What is the size of the conductors you installed?
Click to expand...

200amp breaker at the switch gear
225amp sub panel
50ft
3/0 cabling
 
Key points still misisng:
From Pierre's post:
What is the available fault current at the gear?
What is the rating of the panel you installed?**


**Included in this question, what is the lowest AIC rating of the breakers in that new panel.
The key to the possible violation is in AIC ratings not ampere ratings.
 
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