63 A Two-Pole AC Circuit Breaker

An FE7-63 series AC breaker rated 63 amps across two poles at 400 volts. It clips onto standard DIN rail inside a distribution enclosure.

This is the protection on the AC side of an off-grid system: between the inverter output and the building’s distribution panel, or at the head of a dedicated workshop circuit. The two-pole version breaks line and neutral together, fully isolating the downstream circuit for service.

Never use it on a DC circuit. An AC breaker lacks the arc chutes needed to quench a DC arc and will weld itself closed. For the battery and array sides, use a DC breaker. The same frame is also available in 40 A.