MCCB with a thermal-magnetic release and undervoltage coil
The Siemens SENTRON 3VA1063-4ED42-0DC0 is a 4-pole molded case circuit breaker (MCCB) rated for 63 A continuous current. It carries a TM210 thermal-magnetic overcurrent release — the '210' tells you the thermal pickup is fixed at the frame rating, with magnetic trip adjustable between 5× and 10× In. That makes it a straightforward choice for general line protection where you want simple, reliable overload and short-circuit response without a microprocessor in the trip path. It also ships with an undervoltage release (UVR) fitted — the release is the 3VA9608-0BB25 auxiliary trip unit. That means the breaker will trip if the control voltage drops below a set threshold, which is common on safety circuits or emergency-stop chains where you want the breaker to open when control power is lost. No separate voltage-trip module to order; it's integrated.
Breaking capacity: what the numbers mean at different voltages
The interrupting rating drops as the system voltage climbs — that's normal for any MCCB, but the curve here is worth noting because it stays high well into the 400 V range. At 240 V it's rated for 121 kA, at 415 V it's 75.6 kA, at 440 V it's 52.5 kA, and at 690 V it's 11.9 kA. For a 63 A frame, those are strong numbers; the 75.6 kA at 415 V means it can handle high-fault scenarios on a 400 V distribution board without needing an upstream current-limiting fuse.
Thermal derating — it holds 63 A up to 50 °C
The continuous current rating is 63 A from 40 °C up through 50 °C ambient. At 55 °C it derates to 60.48 A, at 60 °C to 59.22 A, at 65 °C to 57.96 A, and at 70 °C to 56.7 A. That's a gentle slope — about 10% total drop from 40 °C to 70 °C — so if your panel runs warm but stays under 50 °C, you get the full 63 A without any fudge factor. The rated insulation voltage is 800 V, and the front face carries IP40 protection, which is typical for a panel-mounted breaker with a rotary handle.
Physical fit and auxiliary contacts
The breaker measures 70 mm deep, 101.6 mm wide, and 130 mm tall. That 70 mm depth is the dimension to watch when you're laying out the gland plate or door clearance — it's not a shallow unit, so leave room behind the panel for the arc chamber and wiring. The auxiliary contact block is a 2-switch HQ version (two form-C contacts), which gives you status feedback for a PLC or remote indication without needing a separate add-on module.