Edison dual element time-delay class RK5 fuses are recommended for AC power distribution mains, feeders and branch circuits for motors and transformers, or lighting and heating. In ratings up to 600A, ECNR/ECSR series fuses are one of the most popular styles used for industrial applications and offer a minimum time-delay of 10 seconds at 5x fuse rating.
These fuses are recommended for AC power distribution system mains, feeders and branch circuits having inductive loads (motors, transformers) or non-inductive loads (lighting, heating) where the available short-circuit current does not exceed 200,000 RMS symmetrical amperes. These dual element, time-delay fuses have minimum industry standard time-delay of 10 seconds at 5 times the fuse rating (8 sec. minimum for 250V, 30A and less). The time-delay characteristics of these fuses typically allows them to be sized closer to the running ampacity of inductive loads to reduce cost and provide improved overcurrent protection. These fuses will override normal equipment current surges to reduce unnecessary fuse openings. They are the most popular fuses used in the industry and the most economical for most applications, especially motors and transformers. They have moderate current limitation.
Current ratings up to 600 amps on class RK5 current limiting fuses!
A Current-Limiting Fuse meets the following three conditions:
See our catalog to refer to the fuse selection guide, which includes a general summary of the specifications included for each fuse type.
This selection guide does not include the many variables that can exist for specific situations such as local codes, unusual temperature, or other operating conditions.
When selecting fuses, be sure to comply with any applicable PUBLIC SAFETY standards that apply to Overcurrent Protection Devices (OPD).