{"product_id":"fuse-mrbf-kit","title":"MRBF Terminal Fuse Kit (300A) - for TITAN Lithium Batteries","description":"\u003cp style=\"text-align: center; font-size: 1.2em; font-weight: bold;\"\u003e300A · 58V DC · 10kA AIC · Marine-Rated · Ignition-Protected\u003c\/p\u003e\n\u003cp style=\"text-align: center;\"\u003eRecommended for BS 7671 compliance on every TITAN install.\u003c\/p\u003e\n\u003ch2\u003eWhat's in the kit\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 × Blue Sea 5191 MRBF Terminal Fuse Block\u003c\/li\u003e\n\u003cli\u003e1 × Blue Sea 5190 300A MRBF Terminal Fuse\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMounts directly on the M8 positive terminal of any TITAN battery. The block isolates the fuse from accidental shorts and accepts standard 5\/16\" ring terminals (or stacked terminals via the M8 stud).\u003c\/p\u003e\n\u003ch2\u003eWhy we recommend it\u003c\/h2\u003e\n\u003cp\u003eUK caravan, motorhome and marine installs fall under \u003cstrong\u003eBS 7671\u003c\/strong\u003e, which requires a fuse capable of safely interrupting a worst-case short-circuit current. Our BMS shuts down on a short in normal use, but the regulation looks at worst case - and lithium short-circuits can theoretically reach 3,000-6,000A. Standard blade or MEGA fuses cannot interrupt that current; only marine-rated MRBF or Class T fuses are AIC-rated to do so.\u003c\/p\u003e\n\u003cp\u003eWithout a compliant fuse, an insurance claim has an easy line of defence. We sell this kit at minimal mark-up because we'd rather you were covered than not.\u003c\/p\u003e\n\n\u003ch2\u003eImportant: read before installing\u003c\/h2\u003e\n\u003cp style=\"border:1px solid #FFAB00;padding:14px 18px;margin:16px 0;\"\u003e\u003cstrong style=\"color:#FFAB00;letter-spacing:0.06em;\"\u003eHeads up.\u003c\/strong\u003e This is a short-circuit compliance fuse - not a cable-protection fuse.\u003c\/p\u003e\n\u003cp\u003eThe 300A rating was chosen for one reason: to satisfy BS 7671's worst-case short-circuit requirement (and the AIC rules that come with it) without nuisance-tripping on the legitimate inrush currents that a normal lithium install pulls - inverter startup spikes, induction hob ignition, electric winches, big DC-DC chargers running in parallel. It is \u003cem\u003enot\u003c\/em\u003e sized to protect any one specific cable or load downstream of the battery.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eYou remain responsible for the rest of the install.\u003c\/strong\u003e In practice that means one of the following:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eCabling between this fuse and your distribution \/ busbar rated for at least 300A continuous, or\u003c\/li\u003e\n\u003cli\u003eA correctly-sized secondary fuse close to each load - blade, MEGA, mini-ANL or similar - sized to the cable feeding that load.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIf you'd rather a tighter primary rating, MRBF terminal fuses are available from 30A up to 300A in the exact same physical format. We do not currently stock the smaller ratings; Blue Sea Systems, T1 Terminals and most marine suppliers carry them. The block in this kit accepts any of those fuses without modification.\u003c\/p\u003e\n\u003cp\u003eIf you're unsure how to size the rest of your install, please get in touch before fitting. We're happy to talk it through - but the duty of matching fuse rating to cable rating and load demand sits with the installer \/ owner. Don't assume 300A is the right number for your wiring just because it's the number we ship.\u003c\/p\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFuse rating\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e300A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaximum voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e58V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eAIC (Interrupt capacity)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10,000A @ 14V DC · 5,000A @ 32V DC · 2,000A @ 58V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIgnition-protected\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eYes (when block + fuse used together)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal stud\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eM8 (5\/16\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaximum torque\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e8.47 Nm (75 in-lb)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCable terminations\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5\/16\" ring terminals (standard)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTotal weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e~0.10 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eManufacturer\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eBlue Sea Systems (PN 5190 + 5191)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eSpare parts available separately: \u003ca href=\"\/nl\/products\/fuse-mrbf-block\"\u003eMRBF Terminal Fuse Block\u003c\/a\u003e · \u003ca href=\"\/nl\/products\/fuse-mrbf-300a\"\u003eMRBF 300A Fuse\u003c\/a\u003e\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eTechnical reference\u003c\/h3\u003e\n\u003cp style=\"font-size:0.9em;color:#888;\"\u003eDrawings \u0026amp; curves sourced from Blue Sea Systems product documentation.\u003c\/p\u003e\n\u003cfigure style=\"margin: 28px 0;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0884\/4253\/6201\/files\/5191_dim.jpg?v=1777480105\" alt=\"MRBF block dimensioned drawing - Blue Sea Systems 5191\" loading=\"lazy\" style=\"display:block;max-width:100%;height:auto;background:#fff;padding:8px;margin:0 auto;\"\u003e\u003cfigcaption style=\"text-align:center;font-size:0.9em;color:#888;margin-top:10px;\"\u003eFuse block dimensioned drawing - Blue Sea 5191\u003c\/figcaption\u003e\u003c\/figure\u003e\n\u003cfigure style=\"margin: 28px 0;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0884\/4253\/6201\/files\/5191_mount.jpg?v=1777480105\" alt=\"MRBF block mounting diagram - Blue Sea Systems 5191\" loading=\"lazy\" style=\"display:block;max-width:100%;height:auto;background:#fff;padding:8px;margin:0 auto;\"\u003e\u003cfigcaption style=\"text-align:center;font-size:0.9em;color:#888;margin-top:10px;\"\u003eFuse block mounting diagram - Blue Sea 5191\u003c\/figcaption\u003e\u003c\/figure\u003e\n\u003cfigure style=\"margin: 28px 0;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0884\/4253\/6201\/files\/5175-5190_dim.jpg?v=1777480105\" alt=\"MRBF terminal fuse dimensioned drawing - Blue Sea Systems 5175-5190\" loading=\"lazy\" style=\"display:block;max-width:100%;height:auto;background:#fff;padding:8px;margin:0 auto;\"\u003e\u003cfigcaption style=\"text-align:center;font-size:0.9em;color:#888;margin-top:10px;\"\u003eMRBF terminal fuse dimensioned drawing - Blue Sea 5175-5190\u003c\/figcaption\u003e\u003c\/figure\u003e\n\u003cfigure style=\"margin: 28px 0;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0884\/4253\/6201\/files\/mrbf_tcc.jpg?v=1777480105\" alt=\"MRBF terminal fuse trip-delay (time-current) curve - Blue Sea Systems\" loading=\"lazy\" style=\"display:block;max-width:100%;height:auto;background:#fff;padding:8px;margin:0 auto;\"\u003e\u003cfigcaption style=\"text-align:center;font-size:0.9em;color:#888;margin-top:10px;\"\u003eTrip-delay curve - MRBF terminal fuses\u003c\/figcaption\u003e\u003c\/figure\u003e\n","brand":"Blue Sea Systems","offers":[{"title":"Default Title","offer_id":57027526623497,"sku":"MRBF-KIT","price":36.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/4253\/6201\/files\/5191_block.jpg?v=1777480105","url":"https:\/\/titanlithium.co.uk\/nl\/products\/fuse-mrbf-kit","provider":"TITAN Lithium","version":"1.0","type":"link"}