Fuses

One-Time OT and OTN general purpose fuses provide low cost protection for feeder and branch-circuits serving lighting, heating, and other non-motor loads. OT and OTN fuses will safely interrupt available short-circuit currents up to 50,000 amperes in all ratings. OT and OTN fuses are not rejection fuses and care should be taken to ensure that replacement fuses do not have lower interrupting ratings than original fuses. OTN(15-60) satisfy the Canadian electrical code requirement for Type P low melting-point, non-time-delay fuses.

Mersen R-Rated fuses are current-limiting, high interrupting rating fuses intended for the short circuit protection of medium voltage motors and motor controllers. R-Rated fuses are back-up fuses that have a minimum interrupting rating, and must be coordinated with overload relays in combination motor starters. The motor starter manufacturer generally specifies the R-Rated fuse size. These fuses are single, double, triple or quadruple barrels 3 inches diameter with end mounts designed for bolting directly to equipment bus or terminal pads.