Its 4-pole design suits three-phase plus neutral line protection in distribution panels.
Breaking capacity across voltages
Breaking capacity drops as voltage rises: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 3.7 kA at 690 V. For most 400 V-class industrial panels, the 121 kA rating provides generous headroom over typical 50 kA or 65 kA SCCR requirements.
The 140 mm width for a 4-pole MCCB is standard for the 3VA frame size — it occupies the same footprint as other 3VA2125 variants, so a panel laid out for a 3VA2125-8KQ42-0AA0 will accept this unit without rewiring or re-drilling the mounting plate.
Trip unit and protection characteristics
Power loss is 0.6 W maximum — negligible for thermal budgeting inside a crowded enclosure.