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Mersen 30357T - Fuse Block 300VAC 300VDC Class T 30A 2-Pole Copper Box
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Mersen 30357T Fuse Block 300VAC 300VDC Class T 30A 2-Pole Copper Box

Alternate Item Number: 30357T

UPC: 782001675202


Documents & Media
Line DrawingSpecification Sheet

Contact for Pricing

Call +1 (262) 252-1600 (toll-free 877-268-3700) or email [email protected] for pricing and availability.

Overview

The Mersen 30357T is a 2-pole Class T fuse block designed for 300VAC/DC and 30A applications. This model features durable glass-filled polycarbonate (GFPC) insulators with a verified dielectric strength exceeding 2500V, ensuring robust safety. A key differentiator for Mersen Class T fuse blocks is the inclusion of high-conductivity copper alloy connectors, a feature unique to this manufacturer for Class T blocks. These copper connectors are specifically designed for copper wires, offering superior heat cycling performance and meeting or exceeding OEM "no aluminum" specifications. The 30357T utilizes box connectors suitable for wire ranges of #4-14 AWG copper wire, with a recommended torque of 35 in-lbs. This fuse block is UL listed (guide IZLT, File E52283) and CSA certified (class 6225, File 32169), meeting UL 4248 requirements. It accommodates Class T fuses up to 600A and has an SCCR of 200kA. Ideal for applications requiring reliable overcurrent protection with Class T fuses, the Mersen 30357T provides safe and efficient circuit interruption. Proudly manufactured in the US.
  • 300VAC/DC, 30A rating
  • 2-Pole configuration
  • Durable GFPC insulator with >2500V dielectric strength
  • High-conductivity copper box connectors for copper wire
  • UL listed (IZLT, E52283) and CSA certified (6225, 32169)

Specifications

AC Voltage Rating
300 V
Amperage Rating
30 A
Brand Name
Mersen
Class
Class T
Connection
Copper Box
Connection Type
Copper Box
Current Rating
30A
DC Voltage Rating
300 V
Material
Copper, Glass-filled Polycarbonate (GFPC) or Phenolic
Material
Glass Filled Polycarbonate
Maximum Operating Temperature
80 C
Maximum Operating Temperature
80 °C
Mounting
Direct Screw Mount
Number Of Poles
2
Number Of Poles
2-pole
Phase
2
Poles
2-Pole
Size
3.37 x 0.98 x 1.47 in
Size
85.598 x 24.892 x 37.338 mm
Special Features
Unique integral DIN-rail adapters for 600V, 30 & 60A blocks Full barrier design (30 & 60A) increases pole to pole safety Unique adder-block design (30 & 60A) for design flexibility Spring reinforcing standard for all 30 & 60A clips Features high conductivity copper alloy fuse clips Cool running high amperage (100 - 600A) connectors Copper connectors available 30 - 600A
Standard
All fuse blocks meet the requirements of UL 4248 UL listed, guide IZLT, File E52283 UL recognized component guide IZLT2, file E52283 CSA certified class 6225, File 32169
Type
UL/CSA Fuse Bases
Voltage Rating
300 VAC
Package Dimensions (L x W x H)
3.37 in x 0.98 in x 1.47 in
Package Dimensions (L x W x H)
85.598 mm x 24.892 mm x 37.338 mm
Package Weight (Imperial)
0.290 lb
Package Weight (Metric)
0.132 kg
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Frequently Asked Questions

What is the voltage rating for these Class T fuse blocks?

These Class T fuse blocks are available with voltage ratings of 300VAC/DC and 600VAC/DC.

What ampere ratings are available for Mersen Class T fuse blocks?

Mersen Class T fuse blocks are available in ratings of 30A, 60A, 100A, 200A, 400A, and 600A.

What approvals do these Class T fuse blocks meet?

All fuse blocks meet the requirements of UL 4248, are UL listed (File E52283), and CSA certified (File 32169).

What is the SCCR for these Class T fuse blocks?

The Short Circuit Current Rating (SCCR) for these Class T fuse blocks is 200kA.

What type of connectors do these fuse blocks use?

These fuse blocks feature high conductivity copper alloy fuse clips and copper connectors for high amperage applications.

Are these fuse blocks compatible with aluminum wires?

Fuse blocks with a '*' designation have copper box connectors and are for copper wires only.

What are the insulator materials used in these fuse blocks?

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

What safety features are included in the 30A and 60A blocks?

The 30A and 60A blocks feature a full barrier design for increased pole-to-pole safety and an adder-block design for flexibility.

What are the recommended mounting screws for 100A and 200A fuse blocks?

For 100A and 200A fuse blocks, the recommended base mounting screws are #10 (.190" dia.).

What are the recommended mounting screws for 400A and 600A fuse blocks?

For 400A and 600A fuse blocks, the recommended base mounting screws are 1/4" (.250" dia.).

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.