What this MCCB is and what it does
The Siemens 3VA1020-3ED32-0AE0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in three-phase distribution. It carries a continuous current Iu of 20 A at 40 °C, with thermal-magnetic overcurrent release type TM210. The 75.6 kA breaking capacity at 240 V AC means it can safely interrupt a fault current up to that level without upstream damage — critical for high-fault panels where SCCR headroom matters. At 415 V the rating drops to 52.5 kA, and at 690 V to 7.5 kA, so verify the available fault current at your system voltage.
Thermal derating and panel integration
The breaker holds 20 A continuously up to 50 °C ambient; above that it derates linearly to 18 A at 70 °C. In a sealed enclosure or near heat sources, use the 55 °C figure (19.2 A) as your design limit. The 70 mm depth and 76.2 mm width fit standard DIN-rail or panel-mount cutouts — check the 130 mm height for clearance above busbars. IP40 on the front means protected against tools and wires over 1 mm, but not against water ingress; keep it inside a rated enclosure.
Auxiliary contacts and release options
The breaker ships with four auxiliary switches (HQ type) for remote status indication — enough to signal open/closed and trip to a PLC or annunciator. There is no undervoltage release, no shunt trip, and no ground-fault monitoring fitted on this variant. The TM210 release is fixed thermal and magnetic; it is not adjustable for time or current. Latching endurance is rated at 15,000 operations.