What it is and what it does
The Siemens 3VA1050-2ED42-0AE0 is a SENTRON molded case circuit breaker (MCCB) for line protection — the primary feeder breaker in a distribution panel or the main disconnect for a branch circuit. Four poles mean it switches all three phases plus neutral in a three-phase four-wire system, common in North American and some international panels where the neutral needs overcurrent protection. The TM210 overcurrent release is thermal-magnetic: the thermal element handles overloads (inverse-time curve), the magnetic element handles short circuits (instantaneous pickup). Rated 50 A continuous at 40 °C through 50 °C, derating to 45 A at 70 °C — the full thermal curve is documented so you can size the breaker for the actual ambient inside the enclosure without guessing. Insulation voltage rated 800 V, so it's comfortable on 480/277 V and 600/347 V systems with headroom.
Breaking capacity — what the numbers mean for selectivity
The interrupting ratings are voltage-dependent: 52.5 kA at 240 V, 32 kA at 415 V, 13.6 kA at 440 V, and 7.5 kA at 500 V and 690 V. For a 480/277 V panel, the relevant figure is the 440 V rating (13.6 kA) — that's the available fault current this breaker can clear without welding contacts or rupturing. If your service entrance SCCR exceeds that, you need a current-limiting upstream device or a higher-rated frame. The 240 V rating (52.5 kA) matters for single-phase or line-to-neutral faults on a 240/120 V center-tapped system.
Integration notes
Dimensions: 130 mm height, 101.6 mm width, 70 mm depth. Maximum power loss is 14.6 W.
Auxiliary switch configuration
This variant ships with the provision for 4 auxiliary switches HQ (high-qualified) — that means up to four signal contacts can be installed to report breaker status (open/closed, tripped) back to a PLC or annunciator panel. The base switch supplied is order code 3VA10502ED420AA0. No undervoltage release, no ground-fault monitoring, no communication module — this is a plain thermal-magnetic breaker for basic overcurrent protection without add-on electronics.
Environmental and storage range
Operating temperature range -25 °C to 70 °C; storage range -40 °C to 80 °C. The storage range is wider — the breaker can sit in a cold warehouse or a hot shipping container without damage, but the operating derating curve above 50 °C is the real constraint for panel design.