Line protection MCCB with TM210 release — 50 A, 3-pole
The Siemens SENTRON 3VA1050-3ED32-0DH0 is a 3-pole molded case circuit breaker rated for 50 A continuous current (Iu) with a TM210 thermal-magnetic release, designed for line protection in distribution panels. The interrupting ratings climb to 75.6 kA at 240 V and 52.5 kA at 415 V — enough headroom for most industrial service entrances without cascading upstream. At 690 V it still clears 7.5 kA, so it handles mixed-voltage buswork in a single enclosure. The TM210 release is a fixed thermal-magnetic type — no interchangeable trip units, no communication module, no phase-failure detection. That keeps the BOM simple: one part number, one calibration. The undervoltage release (UVR) is built in, so a loss of control voltage drops the breaker open — standard for emergency-stop circuits that need a guaranteed off state when the control supply fails. Auxiliary contacts are 2 form-C plus a separate trip-alarm switch (HQ), giving the PLC a dedicated fault signal that stays latched until the breaker is manually reset. The trip indicator on the front confirms the cause at a glance — no guessing whether it was a manual open or an overcurrent event.
Current derating and panel fit
The 50 A rating holds flat from 40 °C through 50 °C, then derates to 48 A at 55 °C, 47 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. If the panel ambient runs above 50 °C, size the load at the derated value — not the nameplate 50 A. The 70 mm depth and 76.2 mm width fit standard SENTRON mounting footprints; the 130 mm height clears most 200 A and smaller distribution sections without a sub-feed adapter. Front protection is IP40 — fine for a closed panel, but not for washdown or outdoor exposure. The storage range of -40 °C to 80 °C covers unheated warehouses and shipping containers.