Ka rating

[graham123]

I have these two mcbs square d Qox. Both are the same. Both have catagory of duty M2 on the white label. Yet when you peel it away it has an interrupting rating of 10000. So are these 2ka or 10ka? Is interrupting rating same as short circuit capacity?

Graham

 

[Deleted member 9648]

I'd go with M2 as that is what is on the label the manufacturer has supplied for the UK market. Perhaps the 10000 rating is for other markets?

 

[telectrix]

may be wrong, but i'd say 2kA for breaking capacity without the mcb being goosed. 10kA is what it will break, but probably be fried.

 

[Lucien Nunes]

Category of duty ratings to BS3871 are Icn values, so you must take it as 2kA. Agree with Wirepuller that the other rating may have been for different test conditions for 110V systems etc. as I think these were an international product line.

 

[Knobhead]

Best thing to do with them is chuck is find a new home for them, the bin.

 

[davesparks]

The manufacturer deliberately obscured the other information with a label giving new information.
Is it not obvious which information is most up to date, or correct for this market?

 

[Knobhead]

As I recall they are hydromagnetic, about as subtle as a brick to the head. No thermal element.

 

[telectrix]

SOME INFO HERE:

Technical Library - Schneider Electric Schneider Electric