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Mersen RK1 Reducer Fuses

  • rebeccavanessendel
  • May 20
  • 3 min read

Premium Reliable Performance


Mersen's Amp-Trap 2000® time-delay A6D-R fuses provide IEC Type 2 "no damage" protection to existing mains, feeders, and branch circuits serving motor and non-motor loads. A6D-R fuses will open fast enough under extreme fault conditions for maximum short circuit protection to prevent damage to motor starters, switches, and other circuit components, yet also provide the time-delay needed for motor in-rush currents. A6D-R fuses can be used to replace older 600V Class H, K, or RK5 fuses already installed in the field.


Key Features and Benefits


  • Non-indicating or Solid state SmartSpot visual blown fuse indicator

  • Time-delay for motor starting and transformer inrush currents without nuisance opening

  • 600VAC & 600VDC dual rated

  • 300kA interrupting rating - self-certified, UL witnessed tests

  • Extremely current-limiting for low peak let-thru current

  • Recommended for Arc Flash energy reduction

  • Easy 2-to-1 selectivity for prevention of nuisance shut downs and "black outs"

  • Rejection-style design prevents replacement errors (when used with recommended fuse blocks)

  • High-visibility orange label gives instant brand recognition

  • Reduced inventory by taking the place off class RK5, K, and H fuses

  • Metal-embossed date and catalog number for easier traceability and lasting identification

  • Fiberglass body provides dimensional stability in harsh industrial settings


Mersen is the Only Fuse Manufacturer that Offers Reducer Fuses Today


The A2D-R, A6D-R, and AJT Reducer Fuses are a safe, permanent solution for decreasing current rating without using a Fuse Reducer accessory, which is designed for temporary use only. These special purpose UL Listed reduced rating Class RK1 and J fuses provide the same trusted protection levels as a traditional Class RK1 fuses and AJT Class J fuses, but in a larger body.


Reducer fuses are ideally suited for start up or newly expanding manufacturing facilities ramping up production and electrical demand. However, reducer fuses are not just for industrial applications; they can also be suitable for commercial applications as well.


Reducer fuses are designed for simplicity and ease of installation. With tool-less installation, reducer fuses save time and money as compared to fuse reducers.

  • Designed to fit into larger fuse holders with select ratings of class RK1 and J-TD fuses

  • 200A -> 400A and 400A -> 600A

  • Currently offering fixed rating and sizes

  • Other ratings created as requested

  • Category: Special purpose UL listed

  • Stocked product

Applications

  • Motors

  • Safety switches

  • Transformers

  • Branch circuit protection

  • 110-200A Class RK1 and Class J-TD fuses to fit into an associated 400A fuse panel

  • 225-400A Class RK1 and Class J-TD fuses to fit into a 600A fuse panel

  • Minimum arc flash mitigation

  • Permanent use of reduced rating fuses

  • Out-of-the-box fuse installation to eliminate product set up

  • Standard fuse installation and replacement method without the need for special tools

  • Disconnects

  • Control panels

  • All general-purpose circuits

  • Equipment downtime a critical concern

  • High-volume production, non-dispatchable loading, or emergent care environment

  • Low installation and replacement time

  • Premium quality, high reliability needs

  • Maintenance free - no need for periodic inspection

  • Class J reducer fuses can accommodate bolt-in applications

Power-Flo Technologies is proud to partner with Mersen as they're a global expert in electrical power and advanced materials for high-tech industries. Mersen's Amp-Trap 2000® A6D-R fuses and innovative Reducer Fuses offer industry-leading protection and flexibility for a wide range of electrical applications. Whether upgrading existing systems, minimizing arc flash hazards, or seeking a long-term solution for evolving electrical demands, these fuses deliver exceptional performance, reliability, and ease of installation. With time-delay features, high interrupting ratings, and compatibility with legacy fuse classes, Mersen provides a future-ready fuse solution that helps protect equipment, reduce downtime, and simplify inventory. When safety, efficiency, and quality matter, Mersen stands out as the trusted choice.


 
 
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