Mersen OT-45 Class K5 Fast-Acting Amp-Trap® Fuse, 400A/250V

Mersen OT-45 Class K5 Fast-Acting Amp-Trap® Fuse, 400A/250V

The Mersen OT-45 Class K5 Fast-Acting Amp-Trap® Fuse is a One-Time general purpose fuse engineered to protect feeder and branch-circuits serving lighting, heating, and other non-motor loads. Rated 400A at 250VAC/250VDC, this Class K5 fast-acting fuse safely interrupts available short-circuit currents up to 50,000 amperes (50 kA), delivering dependable overcurrent protection where it is needed most. Designed for use on both AC and DC systems at 50/60 Hz, this fuse is available with either Blade or Ferrule style connections, letting installers match the fuse to the physical configuration of their fuse holders and blocks for straightforward, secure installation.

Key Features

• Amperage & Voltage Rating: 400A rated for 250VAC/250VDC circuits, providing reliable overcurrent protection for feeder and branch-circuit, non-motor loads.
• Fuse Class: Class K5 fast-acting construction for consistent, predictable interruption performance.
• High Interrupting Capacity: 50 kA AC maximum interrupting rating/breaking capacity safely clears available short-circuit currents up to 50,000 amperes.
• AC/DC Rated: Suitable for both AC and DC applications, rated at 50/60 Hz frequency for versatile installations.
• Connection Options: Offered in Blade and Ferrule connection styles to fit a range of compatible fuse clips and holders.
• RoHS Compliant: Manufactured to meet RoHS compliance requirements.
• Non-Rejection Fuse: As a non-rejection style fuse, replacement fuses should never carry a lower interrupting rating than the original to maintain system protection.

Certifications & Compliance

• RoHS Compliant

Technical Specifications

• ROHS Compliant: Yes
• AC Max I.R./Breaking Capacity (I1): 50 kA
• Frequency: 50/60 Hz
• Rated Voltage AC UL: 250 V
• Rated Voltage DC UL: 250 V
• Speed/Characteristic: Fast-Acting
• AC or DC: AC/DC
• Fuse Class: Class K5
• Connection Type: Blade or Ferrule

Typical Applications

• Feeder and Branch-Circuit Protection
• Lighting and Heating Circuit Loads
• Non-Motor Load Overcurrent Protection
• Commercial and Industrial Electrical Systems
• General Purpose Circuit Protection Requiring Replacement Fuses

Why Mersen?

Mersen's Amp-Trap® OT-45 Class K5 fuse combines fast-acting protection with a 50 kA interrupting rating to safely clear available short-circuit currents in feeder and branch-circuit applications. Available in Blade or Ferrule connection styles and rated for both AC and DC use, it delivers dependable, code-compliant overcurrent protection for lighting, heating, and other non-motor loads. RoHS compliance further supports its use in demanding commercial and industrial electrical installations where consistent performance and safe replacement practices matter most.