Siemens 3VA2063-5KP32-0AB0 is a SENTRON molded case circuit breaker (MCCB) rated for 63 A continuous current across three poles, fitted with an ETU850 electronic trip unit. The breaker carries 187 kA interrupting capacity at 240 V, 121 kA at 415 V, and 79 kA at 500 V — numbers that tell you it can handle high-fault utility feeds or transformer secondaries without cascading upstream. At 690 V the rating drops to 3.4 kA, so it's not your go-to for 690 V motor branch circuits unless the available fault current is known to be low.
Thermal derating and panel fit
The breaker holds its full 63 A rating up to 50 °C ambient. Above that it derates linearly: 60.6 A at 55 °C, 58.3 A at 60 °C, 55.9 A at 65 °C, and 53.6 A at 70 °C. If your panel runs hot — say a sealed enclosure near a furnace line — that derating curve is what governs the actual load it can carry, not the nameplate 63 A. Dimensions are 105 mm wide, 181 mm high, 86 mm deep — a standard 3-pole MCCB footprint that drops into most SENTRON panelboards and switchgear without re-drilling the mounting plate. Front IP40 protection means it's fine for a clean indoor panel; not rated for washdown.
Trip unit and auxiliary contacts
The ETU850 electronic trip unit provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves — typical for a line-protection MCCB that needs coordination with downstream breakers. It ships with two auxiliary switches (HP version) for status feedback to a PLC or SCADA. Maximum power loss is 5.4 W per pole, which adds up to about 16 W total heat inside the enclosure — worth checking against your panel thermal budget.