AIC Ratings of Gutter Taps

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cpguy33

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I have been confronted by a plans reviewer regarding gutter taps that I have never had a problem with before. They are stating that gutter taps are only allowed for AIC ratings of 10,000 or less as the actual insulated multitap or insulated gutter tap is not rated above that. We have typically been utilizing gutter taped panels in building risers so there is only one riser feeding a panel on each floor. The reviewer is referencing NEC 90.7 and the UL white book. He has also contacted Burndy and they supposedly reinforce his position. Has anyone ever run into this, or even heard of this?
 
AIC stands for Amps Interrupting Capacity, it only applies to devices that attempt to interrupt the flow of current. I doubt that's what they really meant though, I'm just being pedantic. What they are likely thinking is the SCCR; Short Circuit Currect Rating, the ability of any device in a power circuit to withstand the extreme mechanical forces that take place when a short circuit occurs somewhere down stream of it. The SCCR must the higher than the Available Fault Current (AFC). So to that extent, they are probably right. But there are multi-tap devices rated much higher than that, you just have to look around more.
 
Yes, they meant SCCR. I incorrectly typed AIC. Either way do you know of any products such as a Burndy clear insulated multitap or gutter tap, or even from Ilsco or T&B? The response from T&B was that their products are only rated for 10k SCCR. This completely changes the game for service entrance gutters connecting up to 6 disconnects, or gutter taped panelboards on multi story buildings, or even just splices in feeders.
 
Has anyone run a fault current study for this installation? Or if this comes directly from the utility, do you have their value of available fault current?
 
This is a big issue for many projects that I can think of with taps, not just for risers, because this is a common way feeders are extended.

Maybe compression taps are rated higher? I don't see SC listings in the catalogs.
 
charlie b: I am an electrical engineer and I am required to perform fault current studies. The calculated values all vary based on where in the system the gutters are, but typically it is greater than 10,000A especially for 480/277V.

ron: My point exactly. I have never been able to find the SCCR ratings of any taps, splices, or connectors. I know that due to NEC requirements for industrial control panels and HVAC equipment, and UL508A, the manufacturers have started testing power distribution blocks and are rating them around 200,000A SCCR, depending on fuse protection.
 
my understanding is that if it is UL486 listed as a connector no SCCR is required as it takes on the SCCR rating of the conductor.

some splice blocks are actually listed under UL486.
 
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