Mersen Q079433 - Square Body High-Speed Fuse Protistor® Size 72 aR 1200VDC IEC 420A With Striker L Brackets
Mersen

Q079433

Alternate Item Number: D72SG120V420QF


Documents & Media
Specification Sheet

Contact for Pricing

Overview

The Mersen Q079433 Protistor® Size 72 aR high-speed fuse is engineered for DC applications requiring precise protection. This fuse features a 1200VDC voltage rating and a 420A current rating, making it suitable for demanding railway power and auxiliary circuits. The square body design ensures robust mechanical strength, while L-brackets provide secure mounting options. Mersen’s DC semiconductor fuse-links, including the Q079433, deliver superior short-circuit protection with lower I²t values to minimize component damage. They operate effectively at elevated temperatures and offer reduced watt loss for improved efficiency and extended service life. With a UNSPSC code of 39121628 and manufactured in Mexico, this fuse is a reliable choice for modern DC power systems in railway and industrial applications.
  • High-speed fuse for DC applications up to 1200VDC
  • 420A current rating with Size 72 aR semiconductor protection
  • Square body design with L-brackets for secure mounting
  • Operates effectively at elevated temperatures
  • Lower I²t values reduce component damage during faults

Specifications

Amperage Rating
420 A
Application
Protection of inverters Protection of motor drives Protection of UPS systems Railway power and auxiliary circuits ESS Battery Rack protection up to 1500VDC
Brand Name
Mersen
Case
Ceramic
Connection
L Brackets
Current Rating
420A
DC Voltage Rating
1200 V
Mounting
Bolted
Mounting Type
L Brackets
Series
Protistor®
Size
Size 72 aR
Size
Size 72
Size
6.42 x 2.36 x 3.01 in
Size
163 x 60 x 76.5 mm
Special Features
Extremely fast acting Excellent cycling capability Very low I²t Worldwide acceptability Current Limiting Superior Cycling Ability
Standard
IEC 60269-1 and IEC 60269-4 Compliance DC UL recognized component UL file E76491 - 160A-420A, @1200VDC, L/R 10ms, 100KA - 160A-420A, @1500VDC, L/R 1-3ms, 100KA GB/T 13539.4-2016
Sub Brand
Protistor®
Type
Square Body High-Speed Fuse-Links DC Protection
Type Of Indicators
Striker
Voltage Rating
1200 V
Wattage
131 W
Package Dimensions (L x W x H)
6.42 in x 2.36 in x 3.01 in
Package Dimensions (L x W x H)
163 mm x 60 mm x 76.5 mm
Package Weight (Imperial)
2.535 lb
Package Weight (Metric)
1.150 kg
Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount

GPM-SRR90

Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount
Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20

C331156

Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20
Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8

1SCM8

Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8
Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20

E1062696

Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20
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

9F61BWW460

9F61 Size B Clips 1.6in

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.