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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp

Item # 331-BCDC1225D
Our Price: $465.00
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Battery Charger
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331-BCDC1225D - Solar Panels to Auxiliary Battery,Vehicle Battery to Auxiliary Battery Redarc Battery Charger
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Maintain the charge on your RV's battery with this dual-input, DC-to-DC smart charger. Unit installs in your vehicle or trailer and pulls power from your solar panels before tapping into the vehicle battery. Great for boondocking and dry camping. 1-800-940-8924 to order Redarc battery charger part number 331-BCDC1225D or order online at Free expert support on all Redarc products. Great prices and Fastest Shipping for Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp. Battery Charger reviews from real customers.
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Redarc Battery Charger - 331-BCDC1225D

  • RV/Camper
  • Trailer
  • 12V
  • Battery Charger
  • Redarc
  • Solar Panels to Auxiliary Battery
  • Vehicle Battery to Auxiliary Battery
  • Charges/Maintains
  • 75 Ah
  • 200 Ah

Maintain the charge on your RV's battery with this dual-input, DC-to-DC smart charger. Unit installs in your vehicle or trailer and pulls power from your solar panels before tapping into the vehicle battery. Great for boondocking and dry camping.


  • DC-to-DC battery charger draws power from your vehicle to provide power to an auxiliary battery on your trailer or RV
    • Ideal for battery banks rated between 75 and 200 amp-hours
  • Dual-input device can pull power from 2 sources
    • Connect yellow wire to solar panels (sold separately)
    • Connect red wire to 12V or 24V start battery
  • Multi-stage charging algorithm ensures a complete charge on secondary battery without overcharging
    • Boost stage - provides a constant charge while monitoring auxiliary battery voltage
    • Absorption stage - keeps voltage stable to avoid overcharging while bringing battery up to 100-percent charge
    • Float stage - maintains charge on auxiliary battery
  • Solar power capable - solar panels sold separately
    • Charger automatically draws power from panels before tapping into vehicle battery
    • Built-in MPPT regulator ensures most efficient power transfer possible in all conditions
  • Fully sealed construction with fan-free operation ensures durable performance under harsh conditions
    • Tested to ensure operation in temperatures as high as 176 F
    • Protects sensitive electronics from water, dust, and shock
  • Fault recognition technology prevents damage to batteries from voltage spikes, overheating, and reverse polarity connection
  • Battery isolator function prevents charger from pulling power from start battery when vehicle is off
  • Multiple mounting options for convenient installation
    • Secure the unit in the cabin of the vehicle, along a chassis frame rail, in the engine compartment, or on your trailer
    • Cables, fuses (331-FK40 - sold separately), and connectors sold separately
  • Made in Australia


  • Application: 12V or 24V vehicle systems with standard or smart alternators
    • Battery types supported: AGM, gel, standard lead acid, calcium, and Lithium ion (LiFePO4) batteries
  • Overall dimensions: 4-3/4" long x 4" wide x 1-1/2" tall
  • Battery capacity range: 75 amp-hours - 200 amp-hours
  • Maximum charging voltage: 15.3V
  • Output voltage: 12V DC
  • Output power: 375 watts
  • Output current rating (continuous): 25 amps
  • Input current (maximum): 25 amps
  • 2-Year warranty

The Redarc BCDC dual-input battery charger allows for easy charging of a DC battery while you're on the move. Most battery chargers require that you plug into an AC outlet, but this DC-to-DC charger pulls power from your vehicle's start battery instead. The BCDC also has solar power capability so that you can keep your secondary battery charged while you're parked at a remote campsite. This means that you can go off the grid without worrying about being without power.

This charger connects directly to your battery, rather than pulling power from your vehicle via the trailer connector. This is to ensure that it's able to fully charge your auxiliary battery. A standard 7-way trailer connector is limited to 10 or 15 amps of current, which will not be able to fully restore a battery for use. But this charger can transfer up to 25 amps of current to both charge and maintain your auxiliary battery.

Solar Power Compatible with MPPT Regulator

This charger can pull power from 2 different sources. The first input accepts charge from your vehicle's battery. The second input on this dual-input unit is designed to receive power from solar panels (sold separately). The built-in maximum power point tracking (MPPT) regulator on this unit ensures that the charger will get the most power possible from your panels at any given time. An MPPT regulator is able to determine the point at which your solar panels reach their maximum output. Then the regulator can simulate that load on the panels to effectively draw the most power possible. This type of regulator is more effective than traditional ones at gathering power from solar panels and at drawing power in low-light conditions.

Built-in Green Power Priority, or primary solar selection, ensures that power is pulled from your solar panels first. The BCDC will only tap into your vehicle's battery when necessary. This will save your vehicle battery from unneeded stress. It also has a built-in battery isolator function to prevent the charger from pulling power from the start battery when the vehicle is off.

3-Stage Smart Charger

REDARC BCDC Battery Charger LED Indicators

The BCDC battery charger can be used to charge AGM, gel, standard lead acid, calcium, and Lithium ion (LiFePO4) batteries. An LED on the front panel of the unit will illuminate to show the charge profile, confirming that you've wired the charger correctly based on your auxiliary battery type. This LED will be solid while the unit is charging, and it will flash when the unit is in standby mode. Additional LEDs on this panel indicate where the charger is pulling power from, and what stage of the charging process the unit is in.

This smart charger completely and efficiently charges your auxiliary battery in 3 separate stages. This ensures that the battery reaches maximum capacity without being overcharged.

The first stage of the process, the boost stage, begins when you start up your vehicle. In this mode the charger will maintain a constant current to the auxiliary battery to quickly help it regain power.

Once the unit detects that your auxiliary battery is nearing its maximum charge, the charger will move into the absorption stage. In this stage it will slowly supply the needed current to safely reach 100-percent capacity on the auxiliary battery.

The final stage is known as the float stage. In this stage the unit monitors your auxiliary battery for drops in power and supplies the needed current to keep it fully charged. If a drop in power is detected, it will revert back to the first stage and begin the charging cycle over.

Compatible with Smart Alternators

A number of newer vehicles on the market have ECU-controlled, variable-voltage alternators designed to reduce emissions and boost performance. This type of alternator varies its voltage based on the driving conditions. When the alternator voltage is low, the system can drop below 12.7V, which would deactivate a standard isolator or battery charger. However, with the Redarc BCDC battery charger, this is not an issue. Simply connect the blue override wire to the vehicle ignition and the charger will recognize that the car battery is still receiving a charge from the alternator, even if the voltage has dropped. The charger will modify its voltage requirements so that it can continue to pull power until the start battery drops to 12V, as opposed to the standard 13.2V.

Versatile Mounting

This unit can be mounted in a variety of places to best suit your application. Use the 4 mounting tabs to secure the unit in the cabin of your vehicle, along a chassis frame rail, in the engine compartment, or on your trailer. The charger should be mounted as close as possible to the auxiliary battery being charged to prevent current loss. The farther the current has to travel, the more amperage is lost. A larger diameter wire will allow more current to flow through it, which can offset the current loss that occurs with longer lengths of wire. As a result, it is recommended that you use a heavier gauge wire to cover longer distances. The table below outlines the recommended wire size for a given length of cable:

Redarc BCDC Dual Battery Charger Wiring Guide

To ensure a low-resistance connection, you will want to use MIDI fuses (331-FK40 - sold separately) when connecting the BCDC to your batteries.

For a typical lead acid battery setup, refer to the wiring diagram (shown with fuses and optional LED and solar panel - sold separately) below:

Redarc BCDC Dual Battery Charger Standard Lead Battery Wiring Diagram

For a typical Lithium ion (LiFePO4) battery setup, refer to the wiring diagram (shown with fuses and optional LED and solar panel - sold separately) below:

Redarc BCDC Dual Battery Charger Lithium Battery Wiring Diagram

BCDC1225D REDARC In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp

Installation Details 331-BCDC1225D Installation instructions

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp - 331-BCDC1225D

Average Customer Rating:  4.8 out of 5 stars   (94 Customer Reviews)

Maintain the charge on your RV's battery with this dual-input, DC-to-DC smart charger. Unit installs in your vehicle or trailer and pulls power from your solar panels before tapping into the vehicle battery. Great for boondocking and dry camping.


This unit has worked fine for me. Once wired up I can pretty much forget about it and know that it's charging my house battery whenever I start my vehicle. Probably more important is the automatic disconnection it makes from my starting battery & vehicles charging system when I shut down the vehicle. As well the convenience of adding a solar panel to the system to charge the house battery while the unit still AUTOMATICALLY chooses the best option to charge and disconnects anytime I shut down the vehicle. There are a LOT of different devices/ electronics to accomplish this but the Redarc seems to combine many features/connections in one convenient unit. I have not had the solar portion hooked up yet BUT my understanding is that when I get ready to do so I will NOT need to order a separate MPPT charge controller as that is a built in feature of the unit. These units are a bit pricy for up front cost but seems to provide a lot of features all in one compact unit with a fairly simple wire connection to get it up and charging.



A year later and Redarc is still working flawlessly! BatteryLifeline brand seems to be maintained in a strong state of charge. So far this seems to be a high quality and proven unit to do what its advertised to do. And if you have any questions, the guys Down Under in Australia are right on the line to happily help you. Thanks Mates for a great product. Goodayh Mate


The charger works great. Here is a picture of the system I built for it. The battery is a Battle Born 100 amp hour LiFePo, it’s also charged by (2) 100 watt flexible solar panels. It has (2)- 12 volt receptacles, (2)-dual USB receptacles, and a 750 watt modified sine wave inverter. It runs a small refrigerator, led lights, and various other electronic devices flawlessly. I’m very satisfied with the Redarc unit.


Thanks etrailer for bringing this product to the USA market. I found the REDARC chargt talked about on Australian “caravan” blogs before etrailer had it for sale and considered trying to buy it from an Australian vendor. I use the BCDC1225D to charge my 200 amp hour lithium battery in my truck camper. I have 350 watts of rooftop solar and ran 8gauge wiring from the truck battery through a bed mounted Andersen connector. The very compact size of the unit allowed me to tuck it away in a small space in my camper. I wired it up just as suggested in the instructions and it worked perfectly. I’m getting the full 25 amp charge that the solar panels will provide at midday and get the added benefit of being able to charge at the same rate while driving in the dark. The thing works great. Thanks again etrailer for bringing this product to the USA market

Chris J.


I’m still loving my Redarc. Five Stars!


Received the product as expected. Super simple hook up, already have 4 gauge wire tan to the truck. Plugged it in and it’s charging the batteries as expected.


Works well, good hardware solution for second battery charging- only wish it could use the second bat as a jumper for primary- solar charge is a nice feature.


I highly recommend it. Adding a dual battery setup and using the Redarc BCDC1225D to charge it was the best addition to my rig. Very simple to install and customer service is Tier 1.


The right product for new Ranger with a Four Wheel Camper.Install was easy, compact , maintains two deep cycle agm batteries and monitors 100 amp solar for a complete package. Was able replace my 3 way fridge with a 2 way for better service.


Easy to install. Instructions that come with all Redarc products are straightforward. It's working great so far charging a 105 Ah battery that is running a fridge/freezer, some lights, and assorted other gadgets.


"Great piece of kit!" Seriously well worth the beans. The REDARC allows me to charge my trailer battery while towing. The trailer's converter supplies 13.6 VDC, which is not sufficient to charge my on board battery. The REDARC brings this DC voltage up to approximately 14.7 VDC. So my Truck charging system provides the trailer battery while travelling, and the on board trailer converter,(while AC CONNECTED at the site), sends DC voltage to the REDARC via the Solar Panel Input side of the unit, as I do not have a solar panel. I called Australian support number, and asked if this was an acceptable means of connection. They were most helpful and knowledgeable.

Chas. C.


Two camping seasons and ZERO SNAGS with the REDARC BCDC unit! Real nice


Work great. Charges from the trailer plug and a 100 watt solar panel on the roof. Never have to charge the winch battery. No worries all winter when the trailer just sits. Would buy again.

Bob H.


Works great. Don’t have to worry about the trailer battery freezing during the winter.


This thing is amazing and is the solution for anyone who wants to charge a battery more than a few feet from the alternator. I have a truck with a bed mounted battery which is about 22 feet of wiring from the main battery and it charges perfectly. My Dometic fridge in the bed has been running non stop for a year with one small solar panel a marine battery and this charger connected to the alternator and solar


Works as advertised. It bumps the charging voltage from my Tacoma up to where I can get 20 amps charging current into the trailer battery even while the engine idles. The unit makes up for the voltage drop through the trailer 7 pin connector and about 35 feet of wire plus the ground circuit.. The integrated solar controller works as well as the separate controller the REDARC replaced. Installation could be easier, the REDARC unit has large wire pigtails that must be butt spliced. It would be easier if the unit used a clamp style terminal block.


Too easy. Does what it is deaigned to do.
to modify a Law Enforcement Vehicle with limited space.

Voltage and charge test Alesha’s proved “solid”.


I bought this to help manage an auxiliary battery I'm installing in my F150 to run CB and ham radios and other 12VDC gizmos. I bought the 25A unit because I wanted the solar MPPT controller for a small 130W foldup panel I keep in my truck for emergencies. The 12A Redarc unit doesn't have the MPPT controller. I also favored the Redarc unit over a similar Renogy unit because the Redarc unit is much smaller and seems designed to fit into much smaller space. Not knocking the Renogy unit. It just seems designed to fit into a cabinet or closet in an RV. As I won't be installing this for a few weeks, I'll give my initial impressions then update later if can. First, etrailer slapped the postal sticker on the original product packaging. It's bad enough with porch pirates stealing packages when they can't see what's inside. This was just advertising "please steal me". Second, the Redarc unit looks well constructed and designed. The power wires are larger than required for the amperage and are tin-plated for corrosion resistance. However, the three (3) signal wires (orange, blue, and greed) are bare copper. Yes, they aren't carrying current or aren't carrying much current, but they are still susceptible to corrosion, especially if you choose a frame or rail mount outside of the cabin. Third, I disagree with Redarc's suggestion to crimp then solder the power wires. No OEM car manufacturer in the world solders. Anything that vibrates like a car or airplane should only use crimp connections. Vibration will ultimately cause solder joints to fail. Crimping done correctly is gas tight and provides its own strain relief. Finally, I think you can add a switch to the blue wire to manually turn off the alternator input if you so desire. The details vary depending on the alternator type, and I need to experiment with the setup first before giving out wrong information. When/if I post an update, I will provide instructions for the switch.


Fantastic product.! I mounted it on the outside of my power supply box connected to the auxiliary battery on my camp trailer. It’s seen sun, rain, snow, mud and dirt, keeps my battery charged and handles all the switching between solar panel and alternator charging. Made in Australia which is the next best thing to made in the USA.


This redarc unit us excellent. I use it in my fire transit to charge a 100ah lithium battery. I’m not currently using solar so this is b2b charging only but it works great. Voltage sensing turns the unit on and off quickly, the low profile form factor makes it convenient to install and it doesn’t seem to get particularly warm in operation. Couldn’t be happier.


This works as advertised. I charge a battery in my truck camper with the solar input and from the truck alternator. You really need to run large gauge wires from the truck battery to the camper battery though.


I am looking forward to installing this product. My research showed that this is the optimal DC to DC charger for our needs. I don't know if we will make use of the dual input option but I specifically ordered this model in case we decide to add a solar panel in the future.

This unit will be installed in our small vintage Aladdin travel trailer for use during dry-camping trips so that the accessory battery will be charged between campsites where we will have shorter stays and travel frequently between camps.


The product works great - I currently use it in the back of my truck to charge a 100 AH LI battery. My next step is to use the solar charging feature and see how it works swapping back and forth between truck / solar recharge.


I have used this in my custom camper for one year. It is connected to a Size D gel cell enology battery that drives an inverter to power fridge, micorwave, tv and lights. I have never had an issue with vehicle battery or the gel cell even when used overnight. Works as advertised.


I haven't installed yet, but have heard good things about the product. I have a 4x4 that sits at the airport for 6 months, currently being charged by a 170 w solar panel, feeding both battery's, so the redark will provide charging to the second battery when the car is run. With fridge load, solar not enough.


I ordered the BCDC1225 on Friday and received it on Monday, before noon ... how great is that! Everything appears to be in order. I'm looking forward to getting this charger hooked up to run the fans in the trailer that I carry my dogs in (it's a specially designed trailer which remains cool, but moving air keeps them even more comfortable). Notably, the help that I've received even BEFORE ORDERING has been outstanding. I will turn to for all future trailer-related needs.
(Once installed, I'll post a performance review.)


After one year of working with the charger, it performed perfectly with solar or managing the duel battery set up. A no brainer charger.


I recieved the Redarc bcdc 1225d charger today. This will not be installed for awhile but after looking the unit over, seems to be of high quality. Small but somewhat heavy for the size l would think very good internal components. I chose this over others due to what appears as a better water proof unit. Also the wiring is heavier. Im hoping this unit will last yrs in my setup. I gave 4 stars due to non install yet and packaging.


Good quality. Is holding up after a year of use. My trailer stays in the garage most of the time, so this only gets used when I am out camping or leaving it in the drive way on occasion.

Show More Reviews

See what our Experts say about this Redarc Battery Charger

  • Why Would Someone Need Redarc Battery Charger for Trailer Instead of Just Wire from Vehicle Battery
    The Redarc charger part # 331-BCDC1225D is designed for a charging setup that might be a bit more complex than just running a single charge line back to a trailer battery. This method does work, but if the trailer battery also get a charge from a solar panel or you need to prioritize batteries getting charged, or have 12 volt inputs and/or 24 volt inputs this can handle all of that.
    view full answer...
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  • Can Redarc In-Vehicle BCDC Battery Charger Receive Input From Wind Generator
    I spoke with my contact at Redarc regarding the In-Vehicle BCDC Battery Charger # 331-BCDC1225D referenced in your question. He stated that the regulator can indeed handle a wind generator input provided the wind generator's output is regulated between 9-32V and is equipped with a load dump feature. I have attached a short video demonstration on this product along with the written installation instructions that you can also take a look at.
    view full answer...
  • Does A Flexible Solar Panel Require A Controller/Regulator When Connected To Item # 331-BCDC1225D
    A regulator/controller does not have to be installed when connecting a flexable solar panel to the Redarc In-Vehicle BCDC Battery Charger Item # 331-BCDC1225D however, you will not be able to manage how much power you are pulling from your batteries and how much your panels are putting in.
    view full answer...
  • Recommended Battery Charger To Charge and Maintain Trailer Battery
    If you are using 24 amps per night and will be camping for a while, you may want to consider using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. Not only will this allow you to charge your trailer battery much faster from connection to your vehicle, but it also allows you to have a separate power supply like a solar panel to charge your battery and will give you the most power from each or the combination of the two with the internal regulator. If you are interested in...
    view full answer...
  • How to Determine if Vehicle Has Smart Alternator for Using REDARC Battery Charger
    So smart alternators are one that typically have a lower voltage charge when the vehicle is accelerating and then a drastically higher voltage when the vehicle is coasting. This is a way to minimize the load on the engine when needing the power of the engine and then maximize the load when the vehicle is slowing down. Here's how you determine if you have a smart alternator or not: 1. Locate your main vehicle battery 2. Start the engine, ensuring any fans, radio, lights etc. are...
    view full answer...
  • Can Red Arc Charger Charge Two 6 Volt Batteries Wired Together
    You can run two 6 volt batteries two ways. In series which doubles the output voltage to 12 volt or in parallel which keeps the voltage at 6 volts. I attached a diagram that shows how the two setups get wired. The max input current this can handle is 25 amps. This Redarc Charger part # 331-BCDC1225D will charge the batteries if the voltage is 12.
    view full answer...
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  • Does A 2023 Ram ProMaster Have A Smart Alternator
    For the purpose of installing a DC-DC charger like the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D , your 2023 Ram ProMaster 2500 does not have a smart alternator.
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  • Availability of Battery Charger that has 12 Volts for Input and Output
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D is designed to attach to a 12 volt power source and provide a 12 volt charge for a battery.
    view full answer...
  • Recommended Battery Charger for a XS Power XP950 AGM Battery
    To keep your XS Power XP950 charged I recommend using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. The BCDC will actually use the vehicle's alternator to keep the auxiliary battery charged. When the auxiliary battery is fully charged, the unit will automatically redirect maintenance charge power to the starter battery. I have attached a review video on the charger for you as well.
    view full answer...
  • Using the Redarc BCDC1225D Charger to Charge Two Different Batteries
    There is a way to use the Redarc # 331-BCDC1225D charger to individually charge both of your batteries in two locations. First, I would not connect dissimilar batteries together for use or charging. I would complete your truck/refrigerator install as normal except I would put Anderson quick connectors on the black and brown power output. In this way you could connect to either the 110Ah battery in the truck bed, or the 80Ah battery in the trailer. The attached product page has a wiring...
    view full answer...
  • What is Maximum Input Current of Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D
    The input current max that the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D you referenced is 25 amps or 300 watts. That's for solar or from other sources as well.
    view full answer...
  • Does the 2005 Toyota Tundra SR5 Have a Smart Alternator
    Variable voltage alternators, also known as smart alternators, did not start showing up in vehicles until 2010. Since you have a 2005 Toyota Tundra SR5 it is safe to say that you do not have a variable voltage alternator. This means you will not need to use the blue bypass wire when connecting the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp # 331-BCDC1225D.
    view full answer...
  • Adding Solar Panels to Trailer Battery Charging System
    To add solar panels to the battery charging system on your trailer, I recommend looking into the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. This will allow you to use both solar and battery power to charge and maintain your auxiliary battery. I have attached an image that shows and clarifies how the connections will be made using this setup. This charge uses maximum power point tracking technology for the most efficient charge from the solar panels. It will actually keep your...
    view full answer...
    Image 1 for
  • Can Dual Battery Charger be Used to Monitor Two 6V Batteries Connected in Series
    You should be able to use a dual battery charger to monitor your two 6V batteries. I reached out to my contact at Redarc who confirmed this and provided me with a diagram that you would use to install the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. Although the battery charger that you have may be a different brand, you should be able to use the same setup for your application.
    view full answer...
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  • Trailer Battery Charger that Can Use Solar Panels
    To charge the battery in your trailer by using solar panels, I recommend looking at the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. This charger can actually manage input current from up to 2 DC power sources, including solar panels, to charge and maintain 12V batteries. It can be left connected to batteries for months and will keep them at full charge. I have included a short video demonstration on this product so you can get a better look at its features.
    view full answer...
    Image 1 for
  • Battery Charger Recommendation for Getting Power Source From Alternator and Solar Panel
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D is designed to charge a battery with either an alternator or solar panel power source like what you have. This would work well for what you need. The only way to switch the power source from your van battery to the aux batteries would be with a switch setup for each circuit.
    view full answer...
  • Why Must the RedArc Be Grounded to The Battery Rather than Grounding to Chassis?
    I understand the reasoning behind this and I actually installed the first one that way and didn't get the results we wanted. It makes sense to save the expense of the wire and use the chassis. The reason you must run the wire full length is so the current can free flow and give accurate readings to the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1225D. The RedArc products are the best in the industry at making these work everytime and to do that the BCDC needs to have dead accurate...
    view full answer...
  • Comparing RedArc BCDC Charger to Standard 7-Way 12V Battery Charge
    On a typical 7-way, the 12V power coming from that connection will give you a maintenance charge to your trailer battery of 2-4 amps. This is the additional amperage coming from your alternator that is not being used by your vehicle at the time. This normally will only allow your battery to charge to about 80 percent as well. When you use a charger like the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D that power supply will be amplified to 25 amps and will provide you with...
    view full answer...
  • Can Redarc In Vehicle BCDC Charger be Powered from Truck 12 Volt 7-Way Circuit
    Yes you can use the 12 volt accessory circuit of your truck to power the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D and charge your battery. If the 12 volt circuit of your 7-way stays active when the vehicle is powered off you'd want to unplug the connector when not towing so as to preserve the life of the tow vehicle battery. If the circuit turns off when the vehicle is off you wouldn't need to worry about this. You are correct about the fuse too as it would only need to...
    view full answer...
  • Installation Questions About Redarc 331-BCDC1225D In-Vehicle DC to DC Battery Charger
    According to my contact in the tech services department at Redarc Electronics, the input for the charger must be connected according to the instructions, using the positive terminal of the starting battery. The charger will only pull as much current as the alternator will output, so the factory wire will work fine. The charger will continue to charge the auxiliary battery bank until the start battery depletes to 12.7V. It will resume charging the battery bank once the start battery goes...
    view full answer...
  • Installing Redarc In-Vehicle BCDC Battery Charger in 2024 Toyota Highlander Hybrid XLE
    The wiring for the # 331-BCDC1225D would be the same as the diagram below, you're just coming off of that 12V battery in the back instead of your typical battery in the engine compartment. The thing you need to figure out, and that I'm not sure about, is how exactly that battery is recharged. I would ask the Toyota dealer if it will work to connect the battery charger to it. As long as it is getting enough of a charge and you aren't pulling too much power it will be fine. Otherwise, you're...
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  • Can A Redarc Battery Charger Be Used In A Boat Engine Compartment
    I contacted Redarc and the battery charger part # 331-BCDC1225D is suitable for a boat engine compartment. It also works well to replenish larger battery banks such as your 100Ah deep cycle battery. However, Redarc does suggest you upgrade the alternator to cater to the additional power draw of the marine batteries.
    view full answer...
  • Can the 12 Volt Circuit on a 7-Way Power RV Appliances
    I do have a way for you to keep the refrigerator running in your trailer but the 12 volt power circuit on the 7-way trailer connector will not be nearly sufficient for this. You would need to install a standard 12 volt battery on the trailer and then use a battery charger. For a battery charger I recommend the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D which uses the vehicle's alternator to charge the trailer's battery. This option will also allow you to use the refrigerator...
    view full answer...
  • Charging RV Batteries with a Redarc In-Vehicle BCDC Battery Charger
    The Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp # 331-BCDC1225D will allow you to charge your new lithium batteries in your camper using your truck. It has a dual option to hook up to solar panels that have 9-32V power output to charge your batteries as well. Since a lot of newer vehicles have smart alternators which don't allow a high enough voltage to charge the auxiliary battery you'll need the BCDC Battery Charger because it will boost the voltage...
    view full answer...

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Used Picture for Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp

Condition: Like New

Notes: May have damaged packaging or minor cosmetic blemishes.

Our Price: $354.95
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