Derating and thermal management
Above 50 °C it derates linearly: 241 A at 55 °C, 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. Maximum power loss is 48 W.
The 86 mm depth leaves clearance behind most enclosure gland plates — verify against your backpanel depth if the breaker sits near the door. Width of 105 mm for a 3-pole frame is compact for the 250 A class; adjacent breakers or busbar shroud clearance should follow Siemens' specified side gap (typically 0–10 mm, per the installation instructions).
