Schneider Electric G12F4F63 GoPact MCCB 125 4P 63 A 30 kA TM-D Fixed Moulded Case Circuit Breaker

The Schneider Electric G12F4F63 is a 4-pole GoPact MCCB 125 moulded case circuit breaker rated 63 A, built on the 125 A frame with an ultimate breaking capacity (Icu) of 30 kA at 380/415 V AC. Its TM-D thermal-magnetic trip unit gives fixed long-time overload protection (L) and instantaneous short-circuit protection (I) fixed at 10 x In (630 A), fixed-mounted to a backplate for distribution-board incomers and feeders.

Certifications & Standards

• EN/IEC 60947-1
• EN/IEC 60947-2
• EN/IEC 60947-2 Annex H

Selection Notes

The fixed-thermal (F) setting locks Ir at 1 x In (63 A), removing the adjustment dial so the trip point cannot drift after commissioning — the trade-off against the adjustable (A) variant at the same current, which allows the thermal pick-up to be tuned down to 63 A. Choose this fixed version when the circuit's load current is known and stable and a tamper-proof setting is preferred over field adjustability. Rated service breaking capacity (Ics) is 50% of Icu (15 kA of 30 kA) at 380/415 V AC, in line with the 125 A frame's Category A duty. The fourth pole trips the neutral at the same Ir setting as the phases (4P/4D), so the breaker protects a 3-phase-plus-neutral feeder without a separate neutral device.