The Siemens 3VA1220-6MH32-0AH0 is a SENTRON molded case circuit breaker (MCCB) rated for 200 A continuous at 40 °C, with a 3-pole configuration and a TM120M thermal-magnetic overcurrent release. It is designed for starter protection — meaning it handles both motor overload and short-circuit interruption in a single device, which simplifies panel wiring and reduces component count on motor branch circuits.
Breaking capacity by system voltage
This breaker delivers 220 kA at 240 V, 154 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 4.5 kA at 690 V. The steep drop above 500 V means it is not a universal high-voltage MCCB — at 690 V the 4.5 kA rating limits it to low-fault-current applications. For 400 V class panels (common in European industrial mains), the 154 kA figure gives substantial SCCR headroom against most transformer-fed faults.
Thermal derating and installation
Rated 200 A up to 50 °C ambient; above that it derates linearly to 176 A at 70 °C. The 800 V rated insulation voltage (Ui) supports use in 480 V and 600 V class systems with margin. Dimensions are 105 mm wide × 158 mm high × 70 mm deep — fits standard SENTRON 3VA panel cutouts and busbar systems. The auxiliary switch configuration (2 aux + 1 trip alarm) is built in, so no external add-on block is needed for status feedback to a PLC or alarm annunciator.