63 A MCCB with 121 kA interrupting capacity — line protection for distribution panels
The TM220 thermal-magnetic trip unit handles overload and short-circuit faults without external control power. Breaking capacity reaches 121 kA at 240 V AC, tapering to 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 500/690 V — enough for high-fault utility feeds or transformer secondaries. Rated insulation voltage is 800 V, so it can be applied in 480/277 V and 600/347 V panels with headroom. The breaker mounts in a standard distribution panel or enclosure; front-face protection is IP40, meaning tools or fingers won't reach live parts but the unit is not sealed against moisture.
The breaker occupies 101.6 mm width per pole (about 4 in), 130 mm height (5.12 in), and 70 mm depth (2.76 in). Four-pole unit so it needs the full 101.6 mm mounting width; depth stays within standard enclosure clearances for 63 A frame MCCBs.