AIC Ratings for panels and SPD's

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fleshwound

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AIC has always been a trouble spot for me. I'm looking at a job where they spec 65k AIC raiting for the panels and have a quote from someone who is using 10k rated panels with a 65k rated SPD. Would this work?
 
I fail to see any connection between the two. The 10k breakers may be series rated to 65k but, AFIK, the SPD would have no effect.
 
fleshwound said:
AIC has always been a trouble spot for me. I'm looking at a job where they spec 65k AIC raiting for the panels and have a quote from someone who is using 10k rated panels with a 65k rated SPD. Would this work?
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A few things. First, note the difference between AIC and SCCR. Breakers have an AIC, the panelbard itself has a SCCR. The SCCR of the panelboard itself is probably just academic as Im pretty sure anything these days is going to have a 65k SCCR for load centers and 200k for true panelboards).

You may want to clarify if they allow series ratings or want everything rated at 65k (sounds like the latter based on your wording). A "10k rated panel" would only be allowed if they intend to allow series ratings.

One final note, the rating of the SPD is typically NOT the SCCR rating, it is the surge capacity rating. For example, siemens QSPD series have a SCCR rating of 200ka but the surge current protection rating is 65ka.

Note you can get 65KAIC rated 240/120 branch breakers, for siemens its a q120hh. However, like Rob said many people use a 480/277 rated breaker - not sure exactly why, maybe its cheaper, and its probably far more common. For example a siemens BQD is their "standard' 480/277 breaker rated 14k at 480 but 65k at 240v.
 
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