What this MCCB is and what it does
The Siemens SENTRON 3VA2440-6HL32-0DA0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in industrial power distribution. Its adjustable thermal-magnetic trip can be set between 600 A and 4800 A, making it suitable for main feeders or large motor branch circuits where the load current is known and fixed during commissioning. Breaking capacity is rated at 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 9 kA at 690 V. At 690 V the number drops sharply — if your system runs that voltage, verify the available fault current stays under 9 kA or step up to a higher-rated frame. The breaker carries its full 400 A rating without derating across the entire ambient range from 40 °C to 70 °C. That is unusual — most MCCBs start to derate above 40 °C. Here the thermal curve is flat, so you do not have to upsize the frame for a hot panel.
Built-in undervoltage release
This variant ships with an undervoltage release (UVR) fitted as the auxiliary release. That means the breaker trips automatically if the control voltage drops below a set threshold — common in safety circuits where a loss of control power must open the main breaker. No auxiliary switch is included on this version.
Physical fit and panel integration
Dimensions are 110 mm deep, 138 mm wide, and 248 mm tall. The 138 mm width is standard for a 3-pole MCCB in this class — it fits the usual panel cutout and busbar spacing without surprises. Depth of 110 mm leaves room for rear-connected busbars or a cable entry gland plate behind the breaker.
Power loss and thermal management
Maximum power loss is 66 W at rated current. That is moderate for a 400 A frame — plan for ventilation or spacing if multiple breakers are ganged in a sealed enclosure.