The Schneider Electric ENW22351 is a chassis for the EasyPact NW family of air circuit breakers, carrying a rated current of 1250 A at 40 °C across 4 poles with an H breaking capacity code. It is the drawout mounting variant, meaning the breaker mechanism slides into a fixed cradle — the chassis stays in the switchgear cubicle while the breaker unit can be racked out for maintenance or replacement without disturbing the power connections. This is the standard configuration for large low-voltage switchboards where service continuity matters.
If the cubicle ambient runs hotter — say 50 °C inside a packed switchboard — the breaker must be derated per the manufacturer's thermal curve. The H breaking capacity code tells you the interrupting rating at the rated voltage; for the EasyPact NW family, H typically corresponds to 65 kA or 85 kA at 415 V AC (confirm against the specific breaker unit paired with this chassis). The 4-pole configuration covers three-phase plus neutral, common for IT or TN-S distribution where the neutral is switched. Drawout mounting means the chassis has the fixed contacts and racking mechanism; the breaker unit (ordered separately as a plug-in module) slides in and out. Panel cutout dimensions are 560 mm deep by 400 mm wide by 440 mm tall — verify the switchgear cubicle depth before committing the footprint.