MCB AC/DC Series Circuit Breakers Weidmuller MCB AC/DC Series Circuit Breakers are 1-, 2-, and 3-pole thermal-magnetic miniature circuit breakers in accordance with EN 60947-2, UL1077, and UL489 safety certifications. These circuit breakers are equipped with a positively trip-free snap action toggle actuation mechanism, high-rupture capacity, and visual status indication for DIN-rail mounting. The MCB AC/DC circuit breakers feature 120/240/277/480VAC rating and 60 (single pole) or 125 (series double pole) VDC of high-rated interrupting capacities. These devices are easy to visually inspect, switch manually (or remotely trip with shunt trip devices), and monitor using an auxiliary contact.