What this 3VA1220-5MH32-0DC0 is and what it does
The Siemens 3VA1220-5MH32-0DC0 is a SENTRON molded case circuit breaker (MCCB) designed specifically for starter protection — meaning it's built to protect motor starters and their associated control circuits, not just branch feeders. It's rated for a continuous 200 A at 40 °C, and the thermal derating curve is published all the way up to 70 °C, where it still carries 176 A. That's useful if this breaker lives in a warm enclosure near other heat sources. Breaking capacity is voltage-dependent: 187 kA at 240 V, dropping to 121 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 4.5 kA at 690 V. For a 400 V class panel, that 121 kA at 415 V is well above typical fault levels — it'll clear a bolted fault without the arc flash energy climbing into the danger zone for the gear. It ships with an undervoltage release (UVR) and two HQ auxiliary switches already integrated — the basic switch assembly is order code 3VA12205MH320AA0. No communication function on this variant; it's a straight electromechanical protector.
Panel fit and physical integration
The 3VA1220-5MH32-0DC0 measures 105 mm wide, 158 mm tall, and 70 mm deep. That 70 mm depth is the dimension you care about for gland-plate clearance or shallow backpanel enclosures — it's not a deep-frame MCCB. The 105 mm width for a 3-pole 200 A unit is standard for the SENTRON 3VA platform; it'll drop into the same DIN-rail or screw-mount footprint as other 3VA frame-size breakers. Power loss at full load is 44.5 W maximum. That's not trivial in a sealed enclosure — account for the heat when sizing ventilation or calculating internal temperature rise.