What this breaker carries
The Siemens 3VA1050-3ED42-0CH0 is a 4-pole IEC circuit breaker on the 3VA1 frame, rated 50 A with fixed TM210 thermal-magnetic overload protection (Ir = 50 A fixed) and fixed short-circuit pickup at Ii = 10 × In. Breaking capacity is 25 kA at 415 V AC — class N on the 3VA scale, meaning it handles standard industrial fault levels without needing an upstream current-limiting device for most panel feeds. The breaker ships with an undervoltage release (UVR) rated 120–127 V AC 50/60 Hz, two HQ auxiliary switches, and one HQ trip alarm switch. The neutral conductor is unprotected (solid through), and a nut keeper kit is included for panel mounting.
What the ratings mean for the panel
The 25 kA Icu at 415 V sets the maximum fault current this breaker can safely interrupt under IEC 60947-2. For a 400 V distribution panel fed by a transformer sized under 1 MVA, that's usually enough to avoid cascading — the breaker clears the fault before upstream devices trip, provided the prospective short-circuit current at its terminals stays under 25 kA. Fixed Ir at 50 A and fixed Ii at 500 A (10 × In) means no adjustment dials — the overload and short-circuit thresholds are set at the factory. That simplifies ordering but locks the trip curve; if the downstream load changes, the breaker must be swapped, not re-set. The UVR coil drops the breaker on loss of control voltage (120–127 V AC). Common in safety circuits where a machine must power down on undervoltage or emergency-stop. The two HQ aux switches and one HQ trip alarm switch provide status feedback to a PLC or annunciator panel.