Use it for:
• Between solar panels and MPPT inverter - For 2-4 panels in series
• Example: 3x 550W panels = ∼150V 14A - This C40 500V is perfect
• Or 6x panels 550W in 2 strings (2x 3 series) - Use 2x of this breaker
How to wire (critical - DC is polarized):
• Top: + from panels, - from panels (screws with + and -)
• Bottom: To MPPT / inverter PV input
• Blue switch UP = ON, DOWN = OFF
• Mount on DIN rail in your DB box
What it protects:
• Short circuit from panels
• Overcurrent if panels overproduce
• Lets you switch off solar when doing maintenance - Don't disconnect MC4 under load, switch off this breaker first.