NCLR/SCLR Class RK1 Fast-Acting Fuses

NCLR/SCLR Class RK1 Fast-Acting Fuses


Edison NCLR/SCLR Class RK1 fast-acting fuses are recommended for general power distribution system use for main, feeder and branch circuits having a high percentage of non-inductive loads such as heating and lighting. NCLR/SCLR fuses are suitable for circuit breaker protection.

* When NCLR/SCLR fast-acting fuses are used for inductive loads, the fuses usually require oversizing to override normal transient current surges of motors and transformers. Oversizing fuses usually increases fuse and equipment cost and reduces overcurrent protection. (For inductive loads, LENRK/LESRK fuses are recommended). NCLR/SCLR Class RK1 fast-acting fuses are physically interchangeable with other Class R fuses. They will replace Class K or Class H fuses in standard fuse clips.

* When used as recommended by a specific circuit breaker manufacturer for a specific application.



Data Sheet #1313 (NCLR)

Data Sheet #1314 (SCLR)


Catalog Number NCLR, SCLR
Voltage Rating - NCLR - 250Vac
- SCLR - 600Vac
Amps 1 - 600A
Interrupting Rating 200kA RMS Sym
Agency Approvals UL Listed, Class RK1, Guide JDDZ, File E162363; CSA Certified per C22.2, No. 248.12


Self-Certified DC Ratings:

Voltage Rating: NCLR (1-600) 250Vdc; SCLR (1-600) 300Vdc

Interrupting Rating: NCLR/SCLR 10,000 Amps DC


  • No intentional time-delay opens quickly on overload current.


  • Recommended for protection on non-inductive loads such as lighting and resistance heating circuits.
  • Use to protect lower interrupting rating circuit breakers in series rated applications.