Mersen A2K300R - Fuse A2K-R - Class RK1 - Fast-Acting 250VAC 250VDC 300A Blade Amp-Trap®
Mersen

A2K300R

Alternate Item Number: A2K300R

UPC: 782001915346


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Overview

The Mersen A2K300R is a Class RK1, fast-acting Amp-Trap® fuse designed for high-performance overcurrent protection in industrial and commercial applications. Rated at 300 Amperes with a voltage rating of 250VAC/DC, this fuse delivers exceptional short-circuit protection where high fault currents are present. Its high degree of current limitation ensures low peak let-through current, safeguarding sensitive equipment from damaging transients. The rejection-style design prevents replacement with incorrect fuse classes, enhancing system safety and compliance. Engineered for branch and feeder circuits, load centers, panelboards, switchboards, bus ducts, non-inductive loads, and lighting circuits, the A2K300R offers an interrupting rating of 200kA AC and 20kA DC. The durable fiberglass body provides dimensional stability in harsh industrial environments, while the easy-to-read imprint label enables quick identification and replacement. UL listed to standard 248-12 (File E2137) and CSA certified to standard C22.2 No. 248.12, this fuse meets rigorous safety and performance standards. Ideal for applications requiring reliable, high-interrupting-capacity protection.
  • Class RK1 fast-acting fuse with 300A current rating
  • Voltage rating: 250VAC/DC for versatile applications
  • High interrupting rating: 200kA AC / 20kA DC
  • Rejection-style design prevents incorrect fuse replacement
  • Fiberglass body ensures dimensional stability in harsh environments

Specifications

AC Voltage Rating
250 V
Amperage Rating
300 A
Application
Load centers Panelboards Switchboards Bus duct Feeder circuits Non-inductive loads Lighting circuits
Body Material
PolyTube
Brand Name
Mersen
Class
Class RK1
Connection
Blade
Connection Material
Tin-Plated Copper
Current Rating
300A
DC Voltage Rating
250 V
Fuse Class
RK1
Interrupt Rating
200 kA
Material
Fiberglass
Mounting
Clip
Series
A2K-R
Size
8.63 x 2.06 in
Size
219.202 x 52.4 mm
Special Features
Rejection style design prevents replacement by other fuse classes Fiberglass body provides dimensional stability in harsh industrial environments Easy-to-read imprint label for quick recognition and replacement High degree of current limitation for low peak let-thru current
Standard
UL listed to standard 248-12 File E2137 CSA certified to standard C22.2 No. 248.12 Self-certified for DC per UL248
Sub Brand
Amp-Trap®
Type
Class RK1
Voltage Rating
250 VAC
Voltage Rating
250VAC/DC
Package Dimensions (L x W x H)
8.63 in x 2.06 in x 2.06 in
Package Dimensions (L x W x H)
219.202 mm x 52.4 mm x 52.4 mm
Package Weight (Imperial)
1.680 lb
Package Weight (Metric)
0.762 kg
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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.