Siemens 3VA1050-3ED36-0BH0 — SENTRON MCCB for Line Protection
The Siemens SENTRON 3VA1050-3ED36-0BH0 is a 3-pole molded case circuit breaker (MCCB) rated 50 A at 40 °C, designed for line protection in distribution panels and industrial switchboards. It carries a 75.6 kA interrupting capacity at 240 VAC, stepping down to 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at both 500 V and 690 V — giving you the selectivity headroom to coordinate downstream breakers without cascading faults upstream.
What the Ratings Mean for Your Panel
The 50 A continuous rating holds across 40 °C to 50 °C ambient — no derating needed in a typical ventilated enclosure. Above that, it drops linearly to 45 A at 70 °C (the maximum operating temperature). That thermal curve matters when the breaker sits next to other heat sources in a crowded panel. Breaking capacity is voltage-dependent: 75.6 kA at 240 V means it safely clears a bolted fault on a 240 V secondary bus. At 690 V the same breaker still interrupts 7.5 kA — enough for most motor branch circuits but not for high-fault 690 V mains. The rated insulation voltage of 800 V confirms the internal clearances are sized for 690 V line-to-line systems. This MCCB ships with an integrated undervoltage release (UVR) and a pre-configured auxiliary switch block: two auxiliary contacts plus one trip-alarm switch (HQ). The UVR drops the breaker when control voltage falls below the dropout threshold — standard for emergency-stop circuits that need a guaranteed open on power loss. Power loss is 17.1 W at rated load. That's the heat the breaker dumps into the enclosure — factor it into your panel thermal budget if you're stacking multiple MCCBs in a sealed cabinet.
Panel Integration and Mounting
The breaker measures 76.2 mm wide, 130 mm tall, and 70 mm deep — a standard 3-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures without re-drilling. The 3-pole block occupies three modular 25.4 mm units on the rail.