UL Class M (Midget) and UL Class CC Industrial Fuses

OptiFuse's fuse line includes industrial fuses that offer up to 600 V_AC protection for higher power systems in power and generator applications that require UL Class M (Midget) or Class CC fuses.

UL Class M fuses provide supplementary circuit protection. UL Class M (UL 248-4) fuses are intended for overcurrent protection in equipment that requires no branch circuit protection or that has branch circuit protection already installed upstream in the circuit. If the equipment requires branch circuit protection, a Class M fuse must be combined with a branch-rated circuit protector upstream.

UL Class CC fuses are used for branch circuit protection. UL Class CC (UL 248-14) are standalone circuit protectors that require no supplementary protection. They are physically differentiated from the Class M fuse by the rejection feature that prevents the installation of fuses that cannot provide a comparable level of protection into a Class CC fuse block.