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40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger

40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger

Item # 331-FK40
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Redarc Battery Charger - 331-FK40
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Fuse kit contains 4 high-quality, 40-amp MIDI fuses with protective holders. Works with Redarc 25-amp BCDC battery charger (331-BCDC1225D). Fuses protect your setup from potentially damaging overcurrent caused by short circuits or overloads. Call 800-298-1624 to order Redarc accessories and parts part number 331-FK40 or order online at etrailer.com. Free expert support on all Redarc products. Guaranteed Lowest Price and Fastest Shipping for 40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger. Accessories and Parts reviews from real customers.
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Redarc Accessories and Parts - 331-FK40

  • Battery Charger
  • Fuse Kit
  • Redarc

Fuse kit contains 4 high-quality, 40-amp MIDI fuses with protective holders. Works with Redarc 25-amp BCDC battery charger (331-BCDC1225D). Fuses protect your setup from potentially damaging overcurrent caused by short circuits or overloads.


  • Fuse kit ensures that your setup is protected from potentially damaging short circuits or overloads
    • Designed for use with Redarc BCDC 25-amp battery charger (331-BCDC1225D)
  • Fuse holders provide maximum contact with fuse to keep dirt and debris out of contact points
  • Kit includes
    • (4) 40-Amp fuses
    • 2 Fuse holders with hardware
    • 4 Cable crimp lugs
  • 2-Year warranty

FK40 40-Amp Fuse Kit for REDARC In-Vehicle 25 Amp BCDC Battery Charger

Installation Details 331-FK40 Installation instructions

California residents: click here

Video of 40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Redarc 60-Amp MIDI Fuse Kit Review

Today, we're going to be taking a look at Redarc's midi fuse kit. These are available in forty, sixty or one hundred amps. Many of our customers compare these to standard automotive fuses or circuit breakers and the main reason you would want to opt for this fuse over a standard automotive fuse is that the fuse attachment points are screwed down. This ensures that there will be a good connection between our fuse and our circuits for those high amp drawing components.Circuit breakers can typically build heat under long periods of exposure to high amperage draw, which could cause extra resistance and potentially cause that circuit breaker to pop, requiring you to disconnect it to reset it. Whereas these, don't build as much heat and are going to be more suited for those high amp applications these are going to be heavy duty fuses that will give you overload protection for whatever circuits you install them on. What this means, is if you have a short or fault on a circuit on the other side of the fuse, rather than it causing damage to the wiring and circuits on your vehicle, it simply opens the fuse, allows you to make the repairs that you need to fix that wiring and then simply replace it with a new fuse.The kits come with two fuse holders, four fuses and four ring terminals to make connections for your wiring to connect to your fuses on each side.

To mount it, you will need to provide your own screws, they don't come included with the kit. We just use some self tapping screws here, to get this one mounted. Depending on where you mount it, you may want to use a different type of attachment point.Typical applications use this form for high current drawing components, such as numerous lights inside of a camper or RV. We're using ours with our BCDC charging system on our camper here. And, that completes our look at Redarc's midi fuse kit..

Customer Reviews

40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger - 331-FK40

Average Customer Rating:  4.7 out of 5 stars   (11 Customer Reviews)

Fuse kit contains 4 high-quality, 40-amp MIDI fuses with protective holders. Works with Redarc 25-amp BCDC battery charger (331-BCDC1225D). Fuses protect your setup from potentially damaging overcurrent caused by short circuits or overloads.

- 331-FK40

Easy to install. Instruction were spot on. Not a single problem after a year of use. Definitely recommended. Worth the price.

- 331-FK40

Must have perfect for DCdc charger

- 331-FK40

Good fuses!

- 331-FK40

What a difference this makes. Installing this means I have a fully charged battery when I get to camp

- 331-FK40

Quick shipping, Haven’t hooked it up ye t.

- 331-FK40

God little kit, easy to install.

- 331-FK40

Quality items at a fair price.

- 331-FK40

very satified with product and cusomer service.

- 331-FK40

- 331-FK40

- 331-FK40


Ask the Experts about this Redarc Accessories and Parts

  • How to Charge Trailer Battery While Driving
    We do have one part that will allow you to do exactly what you are seeking, which is to charge your trailer's battery while you are driving. To do that you will need the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. This charger will connect to your truck's start battery and give your up to 25 amps of current, will both charge and maintain the battery, and has a built-in battery isolator which means it won't draw from your truck's battery when the truck is turned off. To...
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  • Do I Have to Connect To Battery for 12v Power with RedArc In-Vehicle BCDC
    You will need to connect to the tow vehicle battery in this case. The issue with trying to install and run the RedArc In-Vehicle BCDC # 331-BCDC1225D via the 7 way is that the 10 gauge wiring in a 7 way trailer connector isn't sufficient to provide a charge to your battery. Since this is exactly what you would want to use the BCDC charger for, using it with the 7-Way would almost defeat its purpose so I cannot recommend that you wire it differently in this case. When installing this...
    view full answer...
  • Connecting 25 Amp Redarc In-Vehicle BCDC Battery Charger to Ignition Wire
    Let's start with the ignition wire you were asking about for the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp # 331-BCDC1225D. What you will do is connect the blue wire from the charger directly to an ignition source via 8 gauge wire so it will be a direct connection to wiring that gets power when your ignition is turned on. If you have a smart alternator or have a long run to an ignition source you can also use the 60-Amp Relay Kit for Redarc In-Vehicle...
    view full answer...
  • Parts for 1998 Toyota 4Runner to use Brake Controller and Charge RV Batteries
    First things first, let's start with adding a brake controller to your 1998 Toyota 4Runner; since you have a 4-way already you just need to add the Universal Installation Kit for Trailer Brake Controller # ETBC7. This will give you a 7-way connector, circuit breakers and the rest of the hardware needed to install a brake controller. The brake controller I highly recommend for your 4Runner is the Redarc Tow-Pro Elite Trailer Brake Controller # RED44FR because it is both highly effective...
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  • How To Choose the Correct Redarc In-Vehicle BCDC Battery Charger for Auxiliary Battery On Vehicle
    In order to choose the correct Redarc In-Vehicle BCDC Battery Charger you'll need to know the amp hour capacity of the battery bank. This would not include the starter battery for the vehicle just the auxiliary battery, the starter battery would get more than enough charge from the vehicle's alternator. Therefore, for a single 12 volt battery you'd need part # 331-BCDC1225D which is rated for 75-200 amp hour batteries (Odyssey PC2150 = 100 Ah). The Redarc In-Vehicle BCDC Battery Charger...
    view full answer...
  • Charging Lithium Trailer Batteries While Driving
    Yes, your solution is a DC to DC charger as there is not a "good" way to charge your 100Ahr trailer battery using your Tacoma's 7 pin connection only. You will get some low amperage trickle-charge while hooked up and the alternator running, but not enough to fully charge your trailer battery. For systems where your trailer batteries are rated for 75-200 Amp-hours, use the Redarc # 331-BCDC1225D 25-Amp, Dual-Input DC-DC Charger. You will additionally need three Redarc # 331-FK40, 40-Amp...
    view full answer...
  • Can Redarc BCDC Charger Be Used with 7-Way Connector to Charge Trailer Battery
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D that you referenced could physically be installed so that it uses 12V power from the 7-Way connector on your truck, but it's not going to allow for ideal operation. The problem is that typical trailer connectors use smaller 10 gauge wiring that just isn't capable of allowing enough power to pass through to really charge a battery up. Since this is exactly what you would want to use the BCDC charger for, using it with the 7-Way...
    view full answer...
  • Travel Trailer Battery Charging from the Tow Vehicle 7-Way
    When your trailer is connected to a 7-way like the Pollak Metal 7-Pole, RV-Style Trailer Socket - Vehicle End # PK12703 the pin at the 1 o'clock position is the 12V power that will charge your trailer battery when it is connected to the corresponding pin on your trailer side connector. This will give your trailer battery a slight maintenance charge that is about 2-4 amps depending on what your alternator can put out that isn't being used by your tow vehicle. This will be like a trickle...
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  • Is a Solar Controller Needed to Install Redarc In-Vehicle BCDC Battery Charger
    A solar controller is not required to install the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D, the solar panel does get connected to the charger directly via the yellow wire. As for fuses you will need the 40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger # 331-FK40 which gets installed as per the accompanying photos; it will depend on the type of battery (lead acid or Lithium ion) you are using. I have added a link to a video review of this charger...
    view full answer...
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  • Does The Manager30 Replace Solar Panel Controller
    Yes, the The Manager30 Battery Management System with Lithium Profile # 331-BMS1230S2-NA takes place of the solar controller for your current solar panel system. Solar panel controllers are used to help manage the power coming in from the panels and since The Manager30 does the same thing it actually can't be installed with a solar panel controller. The Manager30 is definitely an upgrade though as it pulls power from the solar panels and your vehicle start batter (via the alternator). It...
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  • Will 130A Alternator in 2019 Toyota 4Runner be Enough to Work with a 40A Charger
    It sounds like you're referring to the 40A Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D for use with your setup. When it comes to chargers it's a little more about what kind of battery bank you're trying to charge up than how much output the alternator has. With that being said, I reached out to my contact at Redarc and he said that you can typically count on about half of your alternator power being able to switch over to their charger systems so your 130A is definitely high...
    view full answer...
  • Installation Kit and Wiring for Redarc In-Vehicle BCDC Battery Charger 331-BCDC1225D
    To install your Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D you can use the matching installation kit # 331-FK40 which includes fuse holders, fuses and cable crimps. Based on the 40-amp value of the fuses supplied in the kit you will be fine with 8-gauge wire for a 12-foot run.
    view full answer...
  • Will Curt C51108 Echo Pass Through 12-Volt Power to Maintain Trailer Mounted Battery
    The 12-volt power circuit on the trailer connector provides the power for the brake controller which can use up to 10 amps per axle. The controller will 'pass through' the 12 volt power feed circuit to the trailer but it won't have too much effect during braking as the entire feed circuit only provides up to 30 amps. The # C51180 Echo needs that direct connection to the car battery in order to function and actuate your trailer brakes. In other words, I wouldn't depend on the 12-volt...
    view full answer...
  • How To Charge Camper Battery From Vehicle Battery While Being Towed
    To charge your battery on your camper properly while towing I recommend the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp Item # 331-BCDC1225D combined with Jumper Cables with Blue Quick Connect - 28' Long Item # 3375601026. Because the BCDC system requires a minimum of 4 guage wire, the clamp connectors on the cables can be removed. Installing the BCDC Charger allows your vehicle to fully charge your trailer battery without draining the vehicle battery,...
    view full answer...
  • Recommended Trailer Wiring, Brake Controller, and Battery Charger for 2011 Ford Edge
    For your 2011 Ford Edge, if you don't already have a trailer hitch receiver I recommend starting with the # e98870. Then for your wiring, I recommend the T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118515 and then using the # ETBC7 wiring kit to get your 7-way. Then use the Tekonsha Prodigy P3 Trailer Brake Controller # 90195 for the trailer brakes. For the power to charge your battery and power the small refrigerators, you will want to use the Redarc In-Vehicle...
    view full answer...
  • Recommended Vehicle to Trailer Battery Charger with Solar Power Option
    The CTEK battery charger # CTEK56353 is a great charger for when you have shore power, but will not work for a vehicle to trailer battery charger. To charge your trailer battery from your Outback 2.5i, you will need a different type of charger. I personally prefer the Redarc In-Vehicle BCDC Battery Charger - Dual Input # 331-BCDC1240D which allows you to charge your battery while your vehicle is not running. This unit has the ability to charge at 40 amps, use solar, and isolate your...
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  • Can UltraSafe Battery Charger with JumpCharge Engine Start be Used with 4-Bank Battery Setup
    The NOCO Genius UltraSafe Battery Charger with JumpCharge Engine Start 329-G15000 (DISCONTINUED) is designed more with a single battery in mind. Since you have a 4-bank battery setup you need the NOCO Genius 10 Battery Charger and Maintainer # 329-GENIUS10.
    view full answer...
  • Recommended Solution for 2017 F-150 Battery Not Charging RV Battery Fully To Run Refrigerator
    I'll start by saying, there's going to be a little bit of a power drop off from the alternator back to the 7 way connector on your 2017 F-150; this is perfectly normal-it's not going to be exactly 12v, but it should be close. When it comes to your 7-way's 12v circuit charging the battery, a lot of this depends on the battery bank size, but refrigerators do use up a significant amount of power and running it off a single battery is extremely difficult. For that reason, you may want to...
    view full answer...
  • Recommended Vehicle to Trailer Battery Charger for Trailer Battery
    Without hesitation, I recommend using a 7-way trailer connector and using the 12V charge line you find at the 1 o'clock position to run to a battery charger and then your trailer battery. Most charge lines only take whatever amperage is not being used by the vehicle and sends it to the trailer battery providing a maintenance charge. Your trailer clearance lights will run without issue using either plug and drawing power from your vehicle, so the 7-way will serve you well for that function...
    view full answer...
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  • Can Inverter Run Off Trailer Battery to Cool Fridge When Driving
    You can absolutely connect the Power Inverter 1000 Watts with Three AC Receptacles # WC3720 as a way to run your Furrion Refrigerator for RVs # FCR17ADA-BL while you are traveling. To do so you would use a battery box like you mentioned, the NOCO Snap-Top Battery Box with Strap for Group 24 to Group 31 Batteries - Vented # 329-HM318BKS, but you would also need a charger for that battery. The charger will take power from your tow vehicle's battery and charge the auxiliary battery which is...
    view full answer...
  • Charging Trailer When Truck Engine Is Running
    You're correct that the 12 volt power circuit from your truck will not effectively charge a trailer battery that is being used to power hungry electrical loads such as a fridge, lights, inverter, etc. The best way to charge a trailer battery is by using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D (25A model) or # 331-BCDC1240D (40A model). These products also have an inbuilt MPPT solar regulator and battery isolator function. The solar regulator will allow you to charge the...
    view full answer...
  • Are Redarc Battery Chargers # BCDC1225D and # BCDC1240D Compatible with AGM and Lithium Batteries
    Yes, both of the BCDC Redarc batteries, part # 331-BCDC1225D and part # 331-BCDC1240D, are compatible with AGM, gel, standard lead acid, calcium, and Lithium ion (LiFePO4) batteries. The wiring configuration will be very similar between the two. You will just need a low voltage disconnect when using the Lithium Ion battery as you can see in the attached photos. To get the proper fuses you will need the 40-Amp MIDI Fuse Kit # 331-FK40 for part # 331-BCDC1225D, or the 60-Amp MIDI Fuse...
    view full answer...
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  • Recommended Wiring Gauge for Redarc BCDC to Dual Battery Setup
    The Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp # 331-BCDC1225D has the equivalent of 10 gauge wires for the power from the battery. It is recommend to install the 40-Amp MIDI Fuse Kit for Redarc In-Vehicle 25-Amp BCDC Battery Charger # 331-FK40 along with 6 gauge wire like the Bulldog Winch Wiring Kit for ATV/UTV Winches - 120" Long Power Lead # BDW20307
    view full answer...
  • Wireless Brake Controller Recommendation for a 2018 Toyota RAV4 XLE with 4-Way Plug
    We actually have the Curt Echo # C51180 which is a wireless controller that has settings adjustable via Bluetooth connection to an Apple/Android smart phone. Simply plug in the Echo, pair the phone to the controller, and you're good to start adjusting any settings and hit the road! You mentioned that you only have a 4-Way on your 2018 Toyota RAV4 so you will need to install the 7-Way RV Upgrade Kit # ETBC7L so that you have your basic trailer light functions as well as 12V power to not...
    view full answer...
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  • How To Keep Trailer Batteries Topped Off While In Transit and Parked
    To keep the batteries topped off while in transit, I recommend to use the Redarc In-Vehicle BCDC Battery Charger - Dual Input part # 331-BCDC1225D in the tow vehicle and charge the trailer batteries through the 7-Way 12V circuit. The Redarc charger will use the vehicle's alternator to fully charge the batteries while in transit. While you are sitting still you can hook a solar panel to the charger to maintain the charge while your trailer is parked. The Redarc chargers feature built-in...
    view full answer...
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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Joshua S
Video by:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Brent H
Installed by:
Brent H
Employee Brian T
Written by:
Brian T
Employee Kristina F
Updated by:
Kristina F

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