Dayton 5MLE2 NDB2Z-63 C50/2 50A 2 Pole HVAC Control

50 A supplemental protector

The Dayton 5MLE2 NDB2Z-63 C50/2 is a two-pole IEC supplementary protector rated at 50 A with a C curve thermal-magnetic trip. It mounts on a DIN rail and uses screw-clamp terminals that accept wire from 14 AWG to 2 AWG. The device carries a 10 kA interrupting rating at 440 V DC and is listed to UL 1077 for supplemental protection applications.

440 V DC interrupting headroom

At 440 V DC the breaker can interrupt up to 10 kA, providing headroom for typical supplemental DC circuits in HVAC equipment. The C curve tolerates moderate inrush without nuisance tripping, while the thermal-magnetic mechanism still opens on sustained overloads. Protection stops at the rated 50 A; circuits requiring higher continuous current or a higher DC voltage rating fall outside this device's scope.

Upgrade from lower-rated DIN breakers

This unit replaces a 1-pole or lower-amperage DIN-rail supplementary protector when a 50 A two-pole DC disconnect is needed. The jump is worth it when the load demands both poles at 440 V DC and the panel can accommodate the 3.21 in by 1.42 in footprint. Installations needing an AC voltage rating, a different trip curve or a higher interrupting capacity must select another product.