63 A SENTRON MCCB with ETU320 — what the ratings mean for a panel build
The Siemens 3VA2063-5HL32-0HL0 is a 3-pole molded case circuit breaker from the SENTRON family, rated for a continuous current Iu of 63 A and configured for line protection with an ETU320 electronic trip unit. That 63 A rating holds flat from 40 °C through 50 °C — no derating needed in a typical warm panel — then drops to 60.6 A at 55 °C and 53.6 A at 70 °C, so the thermal environment inside the enclosure matters if you're pushing the full 63 A. Breaking capacity is the headline number that decides fault-clearing confidence: 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, and 3.4 kA at 690 V. At 415 V — the most common industrial distribution voltage in many markets — 121 kA SCCR means this breaker can interrupt a bolted fault at that level without cascading upstream, which simplifies selective coordination studies. The auxiliary contact block ships with 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (HQ version), plus a shunt trip release (STL) for remote tripping. No undervoltage release, no ground-fault monitoring, no communication function — this is a straightforward line-protection breaker with remote-trip capability, not a metering or power-quality device.
Panel fit and mounting
Dimensions are 105 mm wide, 181 mm high, 86 mm deep — a standard 3-pole MCCB footprint that fits SENTRON mounting plates and DIN-rail adapters. The 86 mm depth leaves clearance for rear-connected busbars in most 400 mm deep enclosures. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss is 5.4 W, which is modest for a 63 A frame and won't drive significant internal heating in a ventilated panel.
Lifecycle and sourcing reality
The base switch is order code 3VA2063-5HL32-0AA0; the integrated auxiliary trip is 3VA9688-0BL30. Both are active line items, which means spare parts and replacement modules are straightforward to source.