High Quality DC Mini Circuit Breaker DC 40A DC 3p 1500V Miniature Circuit Breaker

It is a 3-pole DC miniature circuit breaker rated 40 A and 1500 V DC, engineered for high-voltage photovoltaic arrays. Its 1500 V rating targets large commercial and utility-scale PV plants that use higher system voltages to reduce current and cable losses.

Raising the system voltage from 1000 V to 1500 V allows longer strings and fewer combiners, lowering cable current, conduction losses, and balance-of-system cost. A 1500 V-rated breaker is required because the string Voc can approach that level on cold days; a 1000 V breaker cannot safely interrupt it.

Three poles connected in series share and divide the 1500 V across multiple contact gaps, making it possible for an MCB-sized device to safely interrupt such a high DC voltage. This series-stacked pole arrangement is how small breakers achieve high DC voltage ratings without needing a much larger enclosure.

At 1500 V, a 40 A breaker handles relatively long, high-voltage strings or small combiner outputs where power (V × I) is delivered at lower current. It is selected so that 40 A exceeds 1.25 × the string Isc while remaining below the cable ampacity and inverter input current.

High-voltage DC arcs are far harder to quench, so this breaker uses a multi-gap arc chute with magnetic blowout across all three poles. The magnetic field forces the arc into segmented plates that split, cool, and de-ionize it rapidly, preventing restrike at the elevated system voltage.

Yes — a device rated for a higher voltage can be used on a lower-voltage system as long as its current rating (40 A) and breaking capacity are appropriate. Using a 1500 V breaker on a 1000 V array is safe and gives margin; the reverse (1000 V breaker on a 1500 V array) is not permitted.

It clips onto a standard 35 mm DIN rail inside a DC combiner box rated for 1500 V. Connect the PV string positive (+) and negative (-) to the line terminals and the inverter/monitoring feed to the load terminals, strictly observing polarity. Use 1500 V-rated PV cabling and lugs rated for the voltage.

These breakers are tested to IEC 60947-2 for circuit breakers, with DC rated voltages up to 1500 V and typical breaking capacities in the 6–10 kA class. Installation and selection follow IEC 60364-7-712, and the unit must carry clear 1500 V DC marking to be used on such arrays.

In a series-pole 1500 V breaker, the arc-quenching magnetic blowout and contact gaps are designed around a specific current direction. Reversed polarity can misdirect the arc and reduce interrupting performance, so always connect source (+/-) and load sides exactly as labeled.

Inspect terminals annually for torque and discoloration, and keep the enclosure sealed because 1500 V DC arcs are particularly hazardous. If it trips, verify the string isn't over-currented by shading or a fault, and remember that any breaker which has cleared a major 1500 V fault should be replaced, as internal arc damage compromises future operation.