Mersen A2D50R - Fuse A2D-R - Class RK1 - Time-Delay 250VAC 250VDC 50A Ferrule SmartSpot® Amp-Trap 2000®
Mersen

A2D50R

Alternate Item Number: A2D50R

UPC: 782001990930


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Overview

The Mersen A2D50R Class RK1 time-delay fuse (SKU: A2D50R) delivers IEC Type 2 "no damage" protection for mains, feeders, and branch circuits in industrial applications. Rated for 250VAC/250VDC and 50A, this ferrule fuse features SmartSpot® visual blown-fuse indication and time-delay characteristics to handle motor inrush currents without nuisance tripping. With a 200kA interrupting rating (AC) and 100kA (DC), the A2D50R provides extreme current-limiting performance, reducing peak let-thru current for superior arc flash energy mitigation. Its rejection-style design prevents replacement errors when used with compatible fuse blocks, while the fiberglass body ensures dimensional stability in harsh environments. UL listed to UL 248-12 (File E2137) and CSA certified to C22.2 No. 248.12, the A2D50R replaces older Class H, K, or RK5 fuses, streamlining inventory. Ideal for motor starters, safety switches, transformers, and control panels, this 50A fuse combines fast fault response under extreme conditions with time-delay for safe motor startup. Metal-embossed date and catalog numbers enable easy traceability.
  • 250VAC/250VDC dual-rated, 50A Class RK1 time-delay fuse
  • SmartSpot® visual blown-fuse indicator for quick diagnostics
  • 200kA (AC)/100kA (DC) interrupting rating with extreme current-limiting
  • IEC Type 2 "no damage" protection for motors, transformers, and branch circuits
  • Replaces Class H, K, or RK5 fuses; rejection-style design prevents errors

Specifications

AC Voltage Rating
250 V
Amperage Rating
50 A
Application
Motors Safety switches Transformers Branch circuit protection Disconnects Control panels All general-purpose circuits
Body Material
PolyTube
Brand Name
Mersen
Class
Class RK1
Connection
Ferrule
Connection Material
Tin-Plated Copper
Current Rating
50A
Interrupt Rating
200 kA
Mounting
Clip
Nema Rating
Class RK1
Series
Amp-Trap 2000
Size
3 x 0.81 in
Size
76.2 x 20.574 mm
Size
3 x 0.81;76.2 x 20.574 in;mm
Size
Ferrule
Special Features
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 of 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
Standard
UL listed to standard 248-12 File E2137 DC listed to UL standard 248 CSA certified to standard C22.2 No. 248.12
Sub Brand
Amp-Trap 2000®
Type
Class RK1
Type Of Indicators
SmartSpot®
Voltage Rating
250 VAC
Package Dimensions (L x W x H)
3 in x 0.81 in x 0.81 in
Package Dimensions (L x W x H)
76.2 mm x 20.574 mm x 20.574 mm
Package Weight (Imperial)
0.119 lb
Package Weight (Metric)
0.054 kg
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POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

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Frequently Asked Questions about Mersen

What industries and applications are Mersen products used for?

Mersen products are used across diverse industrial sectors including solar power, electric vehicles, buildings/construction, industrial automation, power distribution, HVAC, elevators, telecommunications, and specialty manufacturing. Key application areas include circuit protection, surge protection, battery module protection, electrical safety systems, and power management for residential, commercial, and utility-scale installations.

What are the main product lines offered by Mersen?

Mersen offers five primary electrical power product lines: IEC and UL/CSA Fuses and Fusegear, Surge Protection, Low Voltage Disconnect Switches, Power Distribution Blocks, and Engineered Solutions. Their comprehensive range includes specialized components like high-speed fuses, modular fuse holders, surge arresters, and custom-engineered electrical protection systems for industrial and power management applications.

What are the key features of Mersen products?

Mersen products feature advanced electrical protection and power management solutions with key characteristics including finger-safe design, compact modularity, and high-performance safety features. Their product lines span electrical power components like fuses, surge protection, power distribution blocks, and specialized solutions for industrial, solar, and building applications. Critical features include UL/CSA approvals, high short-circuit current ratings, and innovative technologies like the Fuse Control™ program that minimize electrical risks and optimize system performance.

What environmental ratings do Mersen products have?

Mersen products meet rigorous environmental ratings across multiple standards, including UL 508A Type 1, 2, 3, 4, 4X, 12, and 13, CSA Type 1, 2, 3, 4, 4X, 12, and 13, and NEMA Type 1, 2, 3, 4, 4X, 12, and 13. They feature IEC 60529 IP66 protection, with enhanced UV inhibitors for outdoor weathering and operating temperatures ranging from -40°C to 130°C (-40°F to 266°F). These ratings ensure superior protection in wet, corrosive, and challenging industrial environments.

What accessories are available for Mersen products?

Mersen offers multiple accessories for their fuse blocks and systems, including safety pullers (DFC3M and DFC3LP), DIN-rail adapters (DRM), bus bars, auxiliary contacts, and specialized mounting hardware. Key accessories include the DFC3M safety puller for 1-1/2" x 13/32" midget or Class CC fuses, the DRM adapter for mounting 303 series fuse blocks on DIN-rail, and UltraSafe fuse module accessories like bus bars and auxiliary contacts that enable module interconnection and monitoring.

How are Mersen products typically installed?

Mersen products are typically installed in electrical distribution systems, control panels, and industrial automation environments using multiple mounting options. These include service entrance panel mounting, distribution panel installation, control panel DIN rail mounting, and custom engineered solutions like Fused Coordination Panelboards. Installation depends on the specific product type, such as fuses, surge protective devices, or switches, and is designed to provide electrical protection and circuit safety in various industrial and commercial applications.

What certifications and standards do Mersen products comply with?

Mersen products are certified to multiple international standards, including UL (Underwriters Laboratories), CSA (Canadian Standards Association), CCC (China Compulsory Certification), and EAC (Eurasian Conformity). Our products meet rigorous safety and performance standards for industrial applications across North America, China, Russia, and other global markets, ensuring compliance and reliability in electrical power and advanced materials solutions.

What technical support does Mersen offer?

Mersen provides comprehensive technical support through multiple channels, including technical experts located in your time zone who can assist with product selection, application guidance, and troubleshooting. Their Fuse Control™ program offers a free Fuse Inventory Audit & Analysis, and customers can access technical resources through their sales representatives and online platform ep.mersen.com.