Old Bus Duct SCCR's

JW9

Member
Location
Michigan
Occupation
Electrical Engineer
Hello,

I am having trouble finding documentation on bus duct SCCR ratings for older Westinghouse Armor-clad busway. ABB now owns this division but theur tech support is no help. Any wisdom on how these are typically rated?
 
Be careful with really old bus way. Prior to the mid 70s busway was often built with the bars separated from each other over their full length. Unless additional bracing was installed their SCCR was fairly low, probably below 22kA.

Starting in the 70s busway, like Westinghouse Pow-R, is often built with the insulated bars all touching each other, so very high SCCR is easy to achieve.

Didn't the Westinghouse LV busduct go to Cutler Hammer and Eaton?
This is a link to some resources for old stuff.
 
Be careful with really old bus way. Prior to the mid 70s busway was often built with the bars separated from each other over their full length. Unless additional bracing was installed their SCCR was fairly low, probably below 22kA.

Starting in the 70s busway, like Westinghouse Pow-R, is often built with the insulated bars all touching each other, so very high SCCR is easy to achieve.

Didn't the Westinghouse LV busduct go to Cutler Hammer and Eaton?
This is a link to some resources for old stuff.
Thanks Jim. We do typically default to 22kA, but it would be nice to have some justification/documentation on why that is to provide to the owner. They have 2 of these old armor-clad busway with an available fault current over 22kA, which would be a violation. ABB owns this product line now as far as I can tell. See: https://electrification.us.abb.com/... BuyLog 2019/13_GE Products BuyLog_Busway.pdf
 
Top