Blue Sea Systems 5191 fuse block terminal mounted on a battery post for DC protection.
Blue Sea Systems 5191 on a battery post demonstrates compact, high-amp protection.
Blue Sea Systems 5191 fuse block terminal offers weatherproof protection for open cockpit boats.

Blue Sea Systems

Blue Sea Systems 5191 Fuse Block Terminal 30-300A | Battery Post Mount

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$31.96

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Why customers choose TaskHolt Tools

Overview

Designed for demanding marine electrical systems, the Blue Sea Systems 5191 fuse block terminal delivers robust protection in a compact form factor. It mounts to a 3/8\" battery post and accepts MRBF fuses from 30A to 300A, offering flexible protection for high-current DC circuits such as main feeders, inverters, windlasses, and bow thrusters.

The unit is built to withstand open cockpit environments and other harsh marine conditions, featuring a weatherproof body and an insulating cap that helps prevent accidental shorts during maintenance. When used with MRBF fuses, the fuse block can be ignition-protected, adding a safety-focused option for ignition-prone installations. Fuses are sold separately, and the block carries a universal fit for a range of configurations.

Key specifications at a glance

  • Voltage max operating: 58V DC
  • Amps max operating per block: 300A
  • Terminal fuses: 30A–300A
  • Terminal stud size: 5/16\"-18 (8 mm)
  • Mounting hole size: 3/8\" (MN10)
  • Mounting type: battery post mount, single 5/16\" stud for wire connections
  • Insulating cap helps prevent shorts during service
  • Ignition protected when used with MRBF fuses
  • Fuses sold separately
  • Fit type: Universal

Typical applications and benefits

  • DC main protection for space-constrained boats
  • Protection for inverter circuits and other high-current loads
  • Windlass and bow thruster circuit protection in compact layouts
  • Weatherproof design suitable for open cockpit and exposed decks

Note: The 5191 is designed to work with MRBF fuses and provides a dedicated connection point for organized wiring. This block is sold as a fuse block terminal without fuses.

FAQ

Q: What are the voltage and current limits of the 5191 fuse block?

A: It supports up to 58V DC and 300A per block, with MRBF fuses from 30A to 300A.

Q: How is the 5191 mounted and is it weatherproof?

A: Mounts on a 3/8" battery post with a 5/16" stud; designed for open cockpit and harsh marine environments.

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