LENRK/LESRK Class RK1 Dual-Element Time-Delay Fuses

LENRK/LESRK Class RK1 Dual-Element Time-Delay Fuses

The application recommended for these fuses is exactly the same as for the Edison ECNR/ECSR fuses except for the advantages of greater current limitation. The Edison LENRK/LESRK fuses have up to 40% more current limitation and up to 350% more Amps-Squared-Second (I2t) limitation under fault conditions than Edison ECNR/ECSR fuses to reduce potential for damage. In addition, LENRK/LESRK fuses allow better selectivity for electrical power system designers and better short-circuit protection for breakers having inadequate interrupting ratings. ECNR/ECSR and LENRK/LESRK fuse lines are physically interchangeable (and electrically interchangeable per UL equipment listing conditions) and are recommended as a practical, economical way to upgrade systems for many situations.


250 Volt LENRK Data Sheets

Data Sheet # 1309 (0-60 Amps)

Data Sheet # 1310 (70-600 Amps)


600 Volt LESRK Data Sheets

Data Sheet # 1311 (0-60 Amps)

Data Sheet # 1312 (70-600 Amps)


Catalog Number LENRK, LESRK
Volts LENRK - 250Vac
LESRK - 600Vac
Amps 0.2 - 600 Amps
Interrupting Rating 200kA RMS Sym.
Current Limiting RK1 Fuse
Agency Approvals UL Listed, Class RK1, Guide JDDZ, File E162363
CSA Certified, HRCI-R per C22.2, No. 248.12


Self-Certified DC Ratings:

Voltage Rating: LENRK (0-60A) 125Vdc; (70-600A) 250Vdc; LESRK (0.25-600A) 300Vdc

Interrupting Rating: LENRK/LESRK 20,000 Amps DC


  • True dual-element spring - trigger construction allows sizing of 125% FLA for motor backup protection.
  • Superior overload and cycling capabilities.
  • Extremely current limiting provides superior short-circuit component protection.


  • Recommended for AC power distribution system mains, feeders, and branch circuits.
  • Protection of motors and motor branch circuits.
  • Type 2 “No Damage” protection for IEC components.
  • All general-purpose applications including lighting, heating and other non-inductive loads.