Westhomes 6ka Double Pole Isolator MCB Circuit Breaker for DC Solar Panel

It is a 2-pole DC miniature circuit breaker with a 6 kA short-circuit breaking capacity, used as a DC-side isolator and overcurrent protector between solar panels and the inverter. Because both poles open together, it physically disconnects both the positive and negative DC conductors from the array.

It means the breaker can safely clear a short-circuit current of up to 6,000 A at its rated voltage without damage. A 6 kA rating is typical for residential and small commercial PV systems where the maximum available fault current from the string and inverter is well below that level.

A 2-pole breaker opens both the positive (+) and negative (-) lines simultaneously. A single-pole isolator would leave one conductor energized even when "off," creating a shock hazard and a path to ground through the array. 2P isolation is the safer and code-preferred arrangement for PV DC sides.

A pure isolator switch only opens the circuit manually for maintenance and does not provide automatic overcurrent or short-circuit protection. This 6 kA double-pole MCB combines isolation with a thermal-magnetic trip that automatically opens on overload or fault, so it both isolates and protects.

It is rated for DC photovoltaic system voltages, commonly up to 1000 V DC, matching typical residential and small-commercial solar arrays. Confirm the exact Ue (rated operational voltage) on the label and ensure it exceeds the cold-weather Voc of your string.

Mount the 2P breaker on a DIN rail in a combiner or DC distribution box. Run the PV positive and negative from the panel strings to the line (source) terminals, observing the +/- polarity, and run the corresponding conductors to the inverter on the load side. Tighten lugs to the manufacturer's torque.

Yes — opening the double-pole handle isolates the entire DC input to the inverter, which is the standard way to shut down the PV array for maintenance. Always verify with a voltage tester that the inverter DC input is dead before working, since the panels remain live in daylight.

It is designed to IEC 60947-2 for low-voltage circuit breakers and used in installations following IEC 60364-7-712 (PV systems). The 6 kA rating and 2P opening are the key characteristics expected of a DC solar isolator certified for photovoltaic service.

If the breaker trips automatically rather than staying open under manual operation, it is detecting an overload or short circuit on the DC side — for example a ground fault, pinched cable, or defective inverter input. Investigate the fault first; a breaker that opens on its own is doing its protective job, not simply acting as an isolator.

This style of 2P DC isolator MCB is offered in standard current ratings such as 16 A, 32 A, 40 A, 63 A, and 80 A. Choose the rating so that In is at least 1.25 × the string Isc and above the normal operating current, while keeping the 6 kA breaking capacity matched to the system's fault level.