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⚡ Fuse your circuits with the fastest, toughest protection on the market!
The Blue Sea Systems 5121 FUSE A3T (Class T) 400 Amp is a high-performance, fast-acting fuse designed for demanding DC electrical circuits in marine, automotive, and industrial settings. With a 20,000 Amp interrupt capacity and energy-efficient design, it delivers reliable, heat-minimized protection to keep your systems safe and running smoothly.
| ASIN | B000MMH1JO |
| Best Sellers Rank | #20,925 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #14 in Cartridge Fuses |
| Brand Name | Blue Sea Systems |
| Color | Black |
| Customer Reviews | 4.7 4.7 out of 5 stars (395) |
| Global Trade Identification Number | 00632085051211 |
| Included Components | FUSE A3T (CLASS T) 400 AMP |
| Item Dimensions | 2 x 4 x 6 inches |
| Item Type Name | FUSE A3T (CLASS T) 400 AMP |
| Item Weight | 1.6 ounces |
| Manufacturer | Blue Sea Systems |
| Material Type | Plastic |
| Maximum Current | 400 Amps |
| Model | 5121 |
| Mounting Type | Durchsteckmontage |
| Specification Met | Sea |
| UPC | 632085051211 |
| Unit Count | 1.0 Count |
| Voltage | 125 Volts |
| Warranty Description | LIMITED WARRANTY |
G**R
Blue Sea Systems 5119 FUSE A3T (CLASS T) 300 AMP
Works great
D**R
What a BEEFY Fuse
Super Stout and high quality. I guess the only way to tell if it works at the AMP rating is when something goes bad. Fuse came in a plastic Zip bag. nothing special.
K**E
Big fuse for big inverter
You get what you pay for and this is a safety item. I trust Blue Seas for exceptional products.
M**S
Exactly what I needed
Worked perfect. Great value. Ordered an extra one for stock.
J**J
Blue Seas is high quality
We trust Blue Seas for high amperage or voltage electrical parts. We don’t use generics here. Great products. This is a spare we ordered “just in case”
P**T
Also fits a 1/2” battery system bus bars
Fuse looks good, haven’t blown one but assume they work as designed. I had previously bought a 350 amp T fuse from another supplier for a lithium battery application, the holes on that would not fit into the battery terminal bus I bought, however this 250 amp did,
A**R
Blue Sea Systems Class T JJN 400 amp Fuse
What can you say about a fuse...it either conducts current, or it breaks the connection? This one resides quietly in one of my trawler's 8D (house battery) boxes between the + cable connection and the pure sine wave inverter. I can only hope it will work as expected to save my thousand dollar inverter if it becomes necessary. I will say I rely on, as many boat owners do, Blue Sea products.
M**O
Saved myself from disaster
Used one of these on a 48V battery pack capable of delivering >500A and I accidentally shorted the terminals on my inverter with a screwdriver. The fuse blew before the BMS even noticed and saved both me and my equipment. Lessons learned: always use class T fuses on high current battery packs, always have an extra fuse on hand, always use insulated screw drivers if you're going to do something dumb like I did, but lastly just don't do anything dumb with live wires!
H**S
Blue sea au top Un classe T parfait pour le parc de batteries
A**R
Expensive yes but better than risking a fire in your rv! I almost made same mistake as others and bought the fuse holder first thinking fuse came with it. They are sold seperately.
W**N
Stabilt
K**H
Only brand l would buy
P**N
Delivered slightly earlier than stated so very happy with that, all well packaged, absolute beasts, it's an interesting difference in heft vs the supposed 200Amp breakers you see on here, makes you wonder...
Trustpilot
1 week ago
1 week ago