KLNR Series - UL Class RK1 Fast-Acting Fuses

Series: KLNR
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

KLNR/KLSR series RK1 fast-acting fuses were the earliest type of current-limiting fuse developed. Their single-element, silver link design enables them to provide fast-acting overload and short-circuit protection. When used to protect inductive loads such as motors, solenoids, and transformers, KLNR/KLSR series fuses must be greatly oversized to prevent opening the fuses on harmless inrush currents. In such applications, KLNR/KLSR series fuses may only provide short-circuit protection.

We recommend using POWR-PRO™ LLNRK/LLSRK series RK1, dual-element, time-delay fuses in all new applications requiring the current-limiting ability of UL Class RK1 fast-acting fuses, or in existing applications where fast-acting RK1 or RK5 fuses have been opening on harmless system surges such as motor starting currents.

Applications:
  • Resistance heaters
  • Lighting circuits
  • Non-inductive loads
  • Molded case circuit breaker load centers and panelboards have increased interrupting ratings when “series rated” with Littelfuse KLNR/KLSR Class RK1 fast-acting fuses. Refer to panelboard manufacturer’s literature for UL Listed combination of fuses and panelboards. Series ratings up to 200,000 amperes are available.
Safety:
  • 200,000 A.I.R. — Reliable interruption of all overcurrents up to 200,000 amperes.
  • Extremely current limiting — Stops damaging short-circuit current faster than any mechanical protective device.
  • Fast-acting — Provides fast-acting protection to equipment such as variable speed drives, rectifiers and other equipment containing surge-sensitive components.
Longer Equipment Life:
  • Current-limiting design reduces damage to equipment caused by heating and magnetic effects of short-circuit currents.
Economical:
  • Extremely current-limiting — often permits use of readily available, less costly equipment.
  • Used as input or output fast-acting fuses for surge-sensitive components, such as variable speed drives and rectifiers, fast acting KLNR/KLSR fuses may prevent opening of expensive semiconductor fuses protecting individual components.
Easy to Use:
  • 200,000 A.I.R. rating minimizes need for short circuit calculations.
Dimensions:
  • Refer to FLNR for KLNR dimensions and FLSR for KLSR dimensions.

Product Literature

Littelfuse POWR-Gard Catalog

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Access specifications, certifications, check availability and order parts below

Catalog #Amps (A)Interrupting RatingOpeningSizeStockSamplesCompare
KLNR001120 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR002220 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR003320 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR004420 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR005520 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR006620 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR008820 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0101020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0121220 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0151520 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0202020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0252520 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0303020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0353520 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0404020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0454520 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0505020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0606020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0707020 kA @ 125 VdcFast-Acting (F)Industrial CartridgeCheckOrder
KLNR0808020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR0909020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR10010020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR11011020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR12512520 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR15015020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR17517520 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR20020020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR22522520 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR25025020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR30030020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR35035020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR40040020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR45045020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR50050020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder
KLNR60060020 kA @ 125 VdcFast-Acting (F)Knife-BladeCheckOrder

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