Ratings and fit
The Siemens 3VM1140-4EE46-0AA2 is a 4-pole IEC circuit breaker from the 3VM1 series, rated at 40 A with a breaking capacity of 36 kA at 415 V AC. This is the class S frame, which means it handles standard industrial fault levels without needing an upstream current-limiting device for most panel feeds. Overload protection is adjustable via the TM220 thermal-magnetic trip unit: Ir is settable from 28 A to 40 A, matching the conductor or load requirement. Short-circuit magnetic pickup is fixed at 10 x In (400 A), which is a typical setting for feeder or distribution circuits where high inrush (like motor starting) is not expected. The N conductor is unprotected — the breaker switches the neutral but does not include an overload or short-circuit element on that pole. This is standard for 4-pole breakers used in TN or TT systems where the neutral is bonded at the source and only needs isolation, not protection.