That rating drives the SCCR (short-circuit current rating) for the entire panel downstream, so it is the number the site electrical engineer checks first when coordinating selectivity with the main breaker.
Overload and short-circuit protection settings
The TM240 thermal-magnetic trip unit gives an In=250 A continuous rating. Overload protection (Ir) is adjustable from 175 A to 250 A via the ATAM dial, so a single breaker frame covers a range of feeder sizes — a 200 A motor branch today, a 225 A feeder next quarter. That band lets the panel builder tune coordination with downstream branch breakers without swapping trip units.
Integrated shunt trip and neutral protection
The factory-fitted shunt trip (STL) operates on 110-127 V DC or AC 50/60 Hz — a remote-trip coil for emergency-stop circuits or supervisory control. The N-conductor protection is set at 100%, so the neutral pole tracks the phase poles.