Mersen 20321 Fuse Block 250VAC 250VDC Class H/K 30A 1-Pole Pressure Plate

All fuse blocks meet UL 4248 requirements, are UL listed (guide IZLT, File E52283), UL recognized component (guide IZLT2, file E52283), and CSA certified (class 6225, File 32169).

These fuse blocks are rated for 250VAC/DC and 600VAC/DC, with amperage ratings of 30A, 60A, 100A, 200A, 400A, and 600A.

For 250V Class R blocks, use A2D-R, A2K-R, or TR-R fuses. For 600V Class R blocks, use A6D-R, A6K-R, or TRS-R fuses.

For 250V Class H & K blocks, use OT, RF, A2Y types 1 & 3, OTN, CRN, or NRN fuses. For 600V, use OTS, RFS, A6Y types 1 & 3, CRS, or NRS fuses.

SCCR ratings vary by fuse class: 10kA with Class H fuses, 50kA with Class K fuses, and 200kA with Class R fuses.

All fuse clips are made of high-conductivity tin-plated copper. Spring-reinforced or non-spring-reinforced clips are available for 30A and 60A, while 100A and above have spring-reinforced clips.

Yes, some fuse blocks are specifically designed with copper box connectors and clips for copper wires only, ensuring compatibility with copper wire's coefficient of expansion.

Insulators are made from molded glass-filled polycarbonate (GFPC) or phenolic, with dielectric strength exceeding 2500V.

For 100A fuse blocks, use 1/4" (.250" dia.) screws. For 200A, 1-pole blocks use #10 (.190" dia.), and for 200A, 3-pole blocks use 5/16" (.313" dia.).

The fuse blocks accommodate a range of stranded or solid copper or aluminum wire, depending on the specific model and connector type.

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.

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.

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.

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.

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.

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.

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.

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.