What this MCCB carries and where it fits
The Siemens SENTRON 3VA2063-5HN36-0CL0 is a 3-pole molded case circuit breaker (MCCB) rated for a continuous current of 63 A, with an ETU350 electronic trip unit. It's built for line protection — meaning it sits on the feeder side of a panel, protecting cables and busbars from overloads and short circuits. The breaking capacity at 240 V is 187 kA, at 415 V it's 121 kA, and at 690 V it drops to 3.4 kA — so this breaker handles high-fault-current scenarios on low-voltage distribution, typical in industrial switchboards and main distribution panels.
Thermal derating and mounting
At 40 °C, 45 °C, and 50 °C the breaker holds its full 63 A rating. Above that it derates: 60.6375 A at 55 °C, 58.275 A at 60 °C, 55.9125 A at 65 °C, and 53.55 A at 70 °C. If you're packing this into a warm enclosure — say a non-ventilated panel near a furnace line — you need to account for that drop. The unit measures 105 mm wide, 181 mm high, and 86 mm deep, which is the standard 3-pole SENTRON 3VA2 footprint; it'll drop onto a DIN rail or bolt directly to the panel backplate. Maximum power loss is 7.9 W, so it won't cook adjacent components in a dense layout.
Trip unit and auxiliary contacts
The ETU350 is an electronic trip unit with an LSIG characteristic (long-time, short-time, instantaneous, ground fault) — though this particular variant does not include ground-fault monitoring. It also has an undervoltage release (UVR) built in, which will trip the breaker if the control voltage drops below a set threshold. The auxiliary contact block is a 2+1+1 configuration: two auxiliary switches, one trip alarm switch, and one electrical alarm switch. That gives you enough status feedback for a PLC or remote indication without needing an add-on module.