The WEG UMBW-1B1-1.5 is a single-pole miniature circuit breaker (MCB) rated for 1.5 amperes and 277/480V AC. It features a B trip curve for general-purpose protection against overloads and short circuits, designed for supplementary protection per UL 1077 standards. This compact breaker is suitable for control circuits, lighting, and equipment branch circuits in industrial and commercial panels.

The UMBW has a range from 1 to 63 Amps, available in 1,2, 3 poles, and B, C, D trip curves. Single pole and multi-pole thermal-magnetic miniature circuit breakers (MCBs) are in accordance with EN 60947-2, UL 1077 and UL 489 for DIN rail mounting with toggle actuation, visual status indication, and high interrupt capacity. A positively trip-free snap action mechanism ensures reliable switching behavior. A range of trip characteristics and add-on accessories make the UMBW suitable for a variety of applications.

• AC and DC voltages available in one series;
• UL489 branch circuit protective device;
• UL1077 equipment protection;
• 17.5mm width per pole;
• Visual status indication;
• Positive trip-free snap action mechanism to ensure reliable switching;
• Cuttable bus bar connecting system.