Circuit Breakers
Circuit Breakers
(OP)
What is the difference between an Ampere Frame and Ampere Trip? Is the "Frame" referring to the case capacity of the device?
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RE: Circuit Breakers
RE: Circuit Breakers
AT has been discussed here before and the consenus was there is not standard for this, IMO it should be the CT size or CT tap if applicable, because when settings get changed the prints are rarly updated.
RE: Circuit Breakers
There can be a 600AF breaker with a 450A rating plug, it will be designated as 600AF/450AT breaker on one-lines, specs etc. For all practical purposes it will be a 450A breaker. The frame size also relates to the physical dimensions so you know how much panel space it would take up.
Look up MCCB info on websites of leading manufacturers like SQD, GE, Eaton etc.
RE: Circuit Breakers
thread238-145514: Please Clarify the concept of Amp Frame and Amp Trip.
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RE: Circuit Breakers
If the Breaker has an Interchangeable Trip, we size our cable/bus to the frame (AF).
Also for a Fuse Holder or a Fused Switch, we'll size to the frame (or the maximum fuse that the holder/switch will accept).
These are UL requirements...See 13.7.9, 10, 11.
From a Breaker manufacturer's perspective: Breakers are described by a Model/Type (usually a couple of letters), and a Frame Size.
The Model/Type will determine the short circuit rating.
The frame size is the maximum size trip the frame will accept (or can be adjusted to.