Mersen S079481 - Square Body High-Speed Fuse Protistor® Size 302 aR 2400VDC IEC 250A With Striker L Brackets
Mersen

S079481

Alternate Item Number: D302SD24C250QF


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Specification Sheet

Contact for Pricing

Overview

The Mersen S079481 Protistor® Size 302 aR fuse-link is a high-speed DC fuse designed for railway power and auxiliary circuits. Rated at 2400VDC and 250A, this fuse minimizes damage during short circuits with lower I²t values compared to conventional fuses. Engineered for elevated operating temperatures, it delivers reduced watts loss and extended service life. The striker L brackets provide visual or remote indication of fuse operation, enhancing system safety and maintenance efficiency. Compliance with IEC standards ensures compatibility with global railway and industrial DC power systems. Ideal for protecting sensitive semiconductor components and high-current DC circuits where fast response and precise fault isolation are critical. Features silver-plated contact surfaces, non-magnetic hardware, and solidified sand for reliable performance in demanding applications.
  • Rated 2400VDC and 250A for high-current DC applications
  • Size 302 aR fuse-link with lower I²t for superior short-circuit protection
  • Striker L brackets enable visual or remote indication of fuse operation
  • Silver-plated contact surfaces and non-magnetic hardware for reliability
  • Compliant with IEC standards for global railway and industrial use

Specifications

Amperage Rating
250 A
Brand Name
Mersen
Case
Ceramic
Connection
L Brackets
Connection Type
L Brackets
Connection Type
Striker L Brackets
Connection Type
With Striker L Brackets
Current Rating
250 A
DC Voltage Rating
2400 V
Material
Die-Cut Elements in Solidified Sand
Material
Silver-plated, non-magnetic hardware
Material
Not explicitly stated
Mounting
Bolted
Mounting Type
Square Body
Mounting Type
L Brackets
Mounting Type
Striker
Mounting Type
Striker L Brackets
Mounting Type
Brackets
Series
Protistor®
Series
Protistor
Size
Size 302
Size
10.55 x 3.03 x 3.41 in
Size
268 x 77 x 86.5 mm
Sub Brand
Protistor®
Type
Square Body High-Speed Fuse-Links DC Protection
Type Of Indicators
Striker
Voltage Rating
2400 V
Wattage
179 W
Package Dimensions (L x W x H)
10.55 in x 3.03 in x 3.41 in
Package Dimensions (L x W x H)
268 mm x 77 mm x 86.5 mm
Package Weight (Imperial)
4.034 lb
Package Weight (Metric)
1.830 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.

LCC5

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.
9F61 Size B Clips 1.6in

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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.