MidNite Solar MNPV3 / MNPV6 / MNPV12 Combiner Breaker Box

The MidNite MNPV series combiner boxes are outdoor rated, weathertight, NEMA 3R powder-coated aluminum enclosures that house circuit breakers and bus bars to join together multiple strings of solar panels in parallel.

Due to maximum input voltage limitations on charge controllers, there is an upper limit on how many panels can be connected in a single series string.  In order to add more panels to a charge controller, strings must be wired in a series-parallel configuration.

Three variations available the MNPV series, all of which fit 1-pole 150V MNPV series breakers, 1-pole 300V MNPV series breakers, and 2-pole 600V MNPV-2PP series breakers:

• MNPV3 which can house up to (3) single-pole circuit breakers or (1) two-pole circuit breaker
• MNPV6 which can house up to (6) single-pole circuit breakers or (3) two-pole circuit breakers
• MNPV12 which can house up to (12) single-pole circuit breakers or (6) two-pole circuit breakers

The internal bus bars are removable and can be excluded for a passthrough configuration as a convenient way to house breakers functioning as a PV disconnect.  Installing a combiner box at a PV array is a fantastic option for transitioning to conduit.

The MNPV series enclosures have various knockouts on the bottom: a single concentric knockout for 1" or 1-1/4" conduit, and multiple knockouts for 1/2" conduit fittings.  The smaller knockouts can be used for, Heyco entry glands allowing raw PV wire coming directly from solar panels to enter, as well as the aforementioned surge protectors.

All versions are ETL listed to UL1741 standards ensuring safety and code compliance.

MNPV series combiners are most popular for ground-mount arrays, affixed to a wall or pole.  They can also be mounted on an angled roof at a slope of up to 3-on-12 (14 degrees).

Even small solar arrays with just one or two strings benefit from the addition of a combiner box.  If you are considering expanding your array in the future, a properly sized combiner box leaves room to connect right in.

A combiner box is the perfect place to install a MidNite Surge Protector so that any high voltage spikes from lightning, cosmic radiation, or an EMP event can be dissipated at the solar array, preventing them from traveling down the line, preventing system damage.

When wiring more than two PV strings in parallel, overcurrent protection (a fuse or circuit breaker) is required to prevent fault current from turning a small fault into a major, catastrophic failure failure - in extreme cases a fire.

MidNite Solar is an American manufacturer and builds the MNPV series in Arlington, WA.  MidNite stands behind their products with a 5-year warranty.