Four poles give you the ability to switch all three phases plus neutral in a single package, which simplifies wiring in three-phase four-wire systems where neutral protection is required. The adjustable thermal-magnetic trip unit is set for line protection — meaning it's tuned for cable and busbar protection, not motor overload curves. Breaking capacity is the headline here: 330 kA at 240 V AC, 242 kA at 415 V and 440 V, 187 kA at 500 V, and still 3.7 kA at 690 V.
Ground-fault monitoring and integration
This variant includes ground-fault monitoring via summation current formation on the L + N conductors — it measures the vector sum of phase and neutral currents to detect leakage to earth. That's a built-in residual current detection function without needing a separate RCD module, which saves a DIN-rail slot and reduces wiring complexity in the panel.
What the 40 A rating means in practice
That's unusual for an MCCB; many competitors start derating above 40 °C. For a panel sitting in a hot plant environment or near a furnace line, this breaker holds its full ampacity without needing to oversize the frame. The adjustable trip range spans 60 A minimum to 480 A maximum — those are the magnetic pickup settings, not the continuous rating. The 16 A initial value is the thermal trip calibration at the low end.