{"product_id":"blue-sea-systems-5191-mrbf-terminal-fuse-block-30a-300a-battery-post-mount-58v-dc-marine-circuit-protection","title":"Blue Sea Systems 5191 MRBF Terminal Fuse Block, Battery Post Mount, 30-300 Amp","description":"\u003cp\u003eThe Blue Sea Systems 5191 is a terminal-mount fuse block built to hold a single MRBF (Marine Rated Battery Fuse) terminal fuse, giving you compact, high-amperage circuit protection right at the battery. It mounts directly onto a 3\/8 inch (MN10) battery post, with one 5\/16 inch stud for the outgoing wire connection, so it takes up minimal space in tight battery compartments. The block accepts MRBF fuses rated from 30 to 300 Amp (fuse sold separately), making it suitable for protecting high-current circuits such as DC main feeds, inverters, windlasses, and bow thrusters.\u003c\/p\u003e\u003cp\u003eRated for up to 58V DC and 300A per block, the 5191 is built for demanding marine electrical systems and is designed to be weatherproof, holding up in small open-cockpit boats and other exposed, harsh-environment installations. A snap-on insulating cap covers the live terminal connection to help prevent accidental shorts from tools or stray metal contact. When used with MRBF fuses, the block is ignition protected, meeting the safety standard required near gasoline engines and fuel systems. The compact housing measures 2.5 inches wide by 2 inches high and is molded from durable plastic to resist corrosion in the marine environment.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Blue Sea Systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e 5191\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Terminal Mount Fuse Block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuse Type Accepted:\u003c\/strong\u003e MRBF (MRBF Terminal Safety Fuse)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuse Amperage Range:\u003c\/strong\u003e 30-300 Amp (fuse sold separately)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage, Max Operating:\u003c\/strong\u003e 58 Volts DC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCurrent, Max Operating:\u003c\/strong\u003e 300 Amps per block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTerminal Stud Size:\u003c\/strong\u003e 5\/16 inch-18 (8 millimeters)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting:\u003c\/strong\u003e Battery post mount, 3\/8 inch (MN10) post, mounting hole size 10 (5 millimeters) 3\/8 inch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Poles:\u003c\/strong\u003e 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Positions:\u003c\/strong\u003e 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Plastic\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e 2.5 inches wide x 2 inches high\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.16 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIgnition Protection:\u003c\/strong\u003e Ignition protected when used with MRBF fuses\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 632085051914\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat fuse does the Blue Sea Systems 5191 fuse block use?\u003c\/strong\u003e The 5191 accepts MRBF (Marine Rated Battery Fuse) terminal fuses ranging from 30 to 300 Amp; the fuse itself is sold separately.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does the 5191 mount to the battery?\u003c\/strong\u003e It mounts directly on a 3\/8 inch (MN10) battery post and provides a single 5\/16 inch-18 (8 millimeter) stud for connecting the outgoing wire.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the maximum voltage and current rating of this fuse block?\u003c\/strong\u003e The Blue Sea Systems 5191 is rated for up to 58V DC and 300 Amps of current per block.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 5191 fuse block waterproof?\u003c\/strong\u003e It is weatherproof and suitable for small open-cockpit boats and other harsh marine environments where the block may be exposed to moisture.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 5191 ignition protected?\u003c\/strong\u003e Yes, the fuse block is ignition protected when used with MRBF fuses, making it suitable for installation near gasoline engines and fuel systems.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat circuits is the 5191 fuse block designed to protect?\u003c\/strong\u003e It is sized for high-current circuits such as DC main feeds, inverters, windlasses, and bow thruster wiring, where a compact, terminal-mounted fuse is needed close to the battery.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 5191 come with a fuse included?\u003c\/strong\u003e No, the block itself ships without an MRBF fuse; the fuse must be purchased separately in the amperage needed for the circuit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the dimensions and weight of the Blue Sea Systems 5191?\u003c\/strong\u003e The 5191 measures 2.5 inches wide by 2 inches high and weighs 0.16 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many circuits can one 5191 fuse block protect?\u003c\/strong\u003e The 5191 is a single-position, single-pole block, so it accepts one MRBF fuse and protects one circuit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 5191 fuse block have any protection against accidental shorts?\u003c\/strong\u003e Yes, it includes an insulating cap over the terminal connection to help prevent accidental shorts from tools or stray metal contact.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the Blue Sea Systems 5191 fuse block made from?\u003c\/strong\u003e The 5191 housing is made from plastic, chosen for its resistance to corrosion in marine electrical environments.\u003c\/p\u003e","brand":"Blue Sea Systems","offers":[{"title":"Default Title","offer_id":48989503914203,"sku":"BSS-5191","price":35.39,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/5191.jpg?v=1784507103","url":"https:\/\/www.goodvibesmarina.com\/products\/blue-sea-systems-5191-mrbf-terminal-fuse-block-30a-300a-battery-post-mount-58v-dc-marine-circuit-protection","provider":"Good Vibes Marina","version":"1.0","type":"link"}