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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
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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 25 Amp RV/Camper,Trailer 331-BCDC1225D
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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. Call 800-298-1624 to order Redarc battery charger part number 331-BCDC1225D or order online at etrailer.com. Free expert support on all Redarc products. Guaranteed Lowest Price 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
  • Battery Charger
  • Redarc
  • 12V
  • 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.


Features:

  • 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


Specs:

  • 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 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   (63 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.

- 331-BCDC1225D
by:

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


Comments
I’m still loving my Redarc. Five Stars!
Chris J - 08/01/2020


- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

"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.


Comments
Two camping seasons and ZERO SNAGS with the REDARC BCDC unit! Real nice
Chas. B - 05/02/2021


- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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 etrailer.com customer service is Tier 1.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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



- 331-BCDC1225D
by:

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



- 331-BCDC1225D
by:

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.


Comments
Works great. Don’t have to worry about the trailer battery freezing during the winter.
Bob H - 01/19/2021


- 331-BCDC1225D
by:

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



- 331-BCDC1225D
by:

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



- 331-BCDC1225D
by:

As always another great product.This the only place I use when I need something for my camper.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

Too easy. Does what it is deaigned to do. Had to modify a Law Enforcement Vehicle with limited space. Voltage and charge test Alesha’s proved “solid”.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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 etrailer.com for all future trailer-related needs. (Once installed, I'll post a performance review.)



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

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.



- 331-BCDC1225D
by:

Great product and works to perfection. Thanks etrailer.



- 331-BCDC1225D
by:

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.


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Ask the Experts about this Redarc Battery Charger

  • Can Redarc In-Vehicle BCDC Battery Charger be Used to Jump Start Battery
    In addition to the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D you need to use a Redarc Smart Start Battery Isolator. I recommend using the Battery Isolator with Wiring Kit # 331-SBI12KIT if you don't already have the fuse kit, or part # 331-SBI12D if you do already have the fuse kit. With the isolator installed you can then connect a push-button into your system to help jump your start battery.
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  • How to Keep Deep Cycle Battery Charged for Winch and Trailer Light Usage
    The positive terminal on your deep cycle battery will connect to the 12V circuit from your 2018 Ram 2500 to provide a maintenance charge and you do ground the battery from the negative terminal to your trailer frame. With that being said, the 12V power from the alternator on your Ram will provide a trickle charge at best (which keeps the battery topped off when not in use) and it won't actually charge the deep cycle battery completely. Since it sounds like you are looking to use...
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  • 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...
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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...
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  • Wiring a Trailer With Dual Batteries and Solar Charger
    Let's try and take this one at a time to make things easier; to start with the black wire from the 7-way plug (the 12V) should be run to the pair of 12V batteries you already have in the battery box. In terms of grounding they will be grounded through your Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. The LED lights each need to be grounded to the frame of your trailer; they will also be connected to the 12V batteries which would be connected to the charger. That covers...
    view full answer...
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  • Choosing Between The Redarc 25 amp or 40 amp Model For A 2018 RAM Promaster 1500
    Your 180A alternator will work fine with any of their BCDC models. Whether you need a 25, 40 or 50A model will depend on the size of the battery bank you’re planning to charge. If its between 75-200Ah the # 331-BCDC1225D model will be fine but if its greater than 200Ah either the # 331-BCDC1240D or # 331-BCDC1250D will work best to replenish the battery bank faster. Yes, the BCDC can accept unlimited solar Watts/ Amps but its output is limited by the model chosen (i.e. 25, 40 or 50A). Yes,...
    view full answer...
  • How to Jump Start Vehicle Battery From Aux Battery with Redarc BCDC Charger
    Than you so much for your recent purchase! If you want to be able to jump start your vehicle's battery using the auxiliary battery your best option really is to add the Redarc Smart Battery Isolator (SBI) # 331-SBI12 to your existing setup that includes your Redarc BCDC Charger # 331-BCDC1225D. I reached out to my contact at Redarc and this is the specific isolator they recommended to work with this charger for this purpose. I have attached a wiring diagram that you might also find...
    view full answer...
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  • How to Determine if 2017 Ford E-450 Has Smart Alternator
    Thank you for all of the information! In order for the alternator on your 2017 Ford E-450 to be a smart alternator there needs to be some type of sensor to read loads; this is typically found on the negative battery terminal. If you check out the attached photo I received from Redarc you can see an example of what that sensor would look like. I'll address your questions in order, but the ultimate answer is that the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D (for standard...
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  • Is DC-to-DC Charger Required To Use Power Sonic RV Lithium Battery LiFePO4 PS94FR?
    You do not need to have a DC-to-DC charger like the Redarc # 331-BCDC1225D installed in your trailer to use the Power Sonic RV Lithium Battery - LiFePO4 - Bluetooth - Group 27 - 12V - 100 Amp Hour # PS94FR you have. You can hook the battery directly to the 12v power circuit of your tow vehicle, but this will not charge up the battery. It will only put a maintenance charge on the battery due to that circuit having so little of an amp rating. Since you are not worried about having the...
    view full answer...
  • 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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  • Parts Needed to Protect Trailer Battery from Overcharge Due to Vehicle Battery
    The 12V power from your 2006 Ford F-150 will actually only trickle charge the battery on your trailer, meaning the charge rate is very slow. If you are using your battery on a regular basis then it would be more beneficial to use a charger like part # CTEK56353 when you are parked than it would be to rely on your alternator to charge the battery. With that being said, we do have a selection of battery charger/maintainers that you can add to your setup to help protect your battery. I...
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  • What Ignition Circuit Does 60-Amp Relay Kit for Redarc # 331-BCDC1225D Wire To
    The pin of the relay that comes with the # 331-RK1260 that runs to "ignition" only needs a power source that is active when the key is on to basically tell the relay to activate. You don't have to actually splice into ignition wiring. So basically any circuit on the vehicle that is only active when they key is on would work when installing the # 331-BCDC1225D.
    view full answer...
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  • Installing Redarc BCDC Battery Charger # 331-BCDC1225D for Charging Trailer Battery
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D that you referenced is a perfect option to not only maintain the charge on your trailer's battery but actually charge it up during travel. This is because the charger will provide a continuous output of 25 amps (much more than just running a dedicate wire from the tow vehicle's battery to a 7-Way connector). This particular charger also has the ability to accept power input from solar panels for added efficiency if you ever decide...
    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...
  • Can a 12V Battery be Connected in Parallel to Two 6V Batteries That are Connected in Series
    No, connecting your 12V battery in parallel to your 6V batteries that are connected in series will not hurt it. Since everything will be rated for 12V you will be good to go! If this is on a trailer and you don't already have a way to charge the batteries then I highly recommend using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D which also allows you to connect a solar panel like # 34273836 to help with the charging.
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  • 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,...
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  • How To Charge a Trailer Battery Without Killing the Tow Vehicle Battery
    I know this may be more than you are looking to spend but the 7-way circuit on your tow vehicle is not going to have all the functions are you looking for so your only option to obtain these would be with an actual battery charger, the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1225D . The BCDC uses power from the vehicle's alternator so you don't have to worry about it killing the tow vehicle's battery. The BCDC will also provide an actual charge for the trailer battery whereas...
    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...
  • Will the Redarc BCDC Battery Charger Help to Bring an Optima Yellow Top Battery to Full Charge
    You are correct, that an alternator is not designed to fully charge a depleted battery. In your case the Optima yellow top is being significantly discharged and will eventually need to be charged with a good battery charger like the CTEK MULTI US 7002, # CTEK56353. The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D can be used to boost the charge that your alternator is sending to the second (in this case yellow top) battery that you are using to power the fridge. This will not...
    view full answer...
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  • 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...
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  • 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...
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  • How do I Know if I Have a Smart Alternator?
    The best way to tell is to look for the sensor on the battery. Variable Voltage Alternators require some sort of battery sensing technology to determine load coming from the battery and this is done by a battery sensor which is found on one of the battery terminals (usually the battery negative).
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  • Using Redarc BCDC Charger to Charge Secondary Battery on GMC Yukon
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D that you referenced is exactly what I recommend for this application and it will work perfectly. This charger is specifically designed to not just maintain but charge up a secondary battery while driving with its multi-stage charging design that boosts the charge (up to 25 amps) from the truck's battery. Even if the secondary battery were to get low on power you don't have to worry about any damage being done to the alternator....
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  • 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...
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  • 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...
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  • How To Charge a Trailer Battery For Refrigerator While Driving Down the Road
    In order to charge a trailer battery while driving you really only have one option which is to use the vehicle's alternator. In order to do this you need a device sophisticated enough to take the correct amount of charge without causing issues to the vehicle's battery while also ensuing your are not overcharging the trailer's battery. Furthermore, you will need to isolate the two batteries so there aren't any issues with shorts. For this, we have the Redarc In-Vehicle BCDC Battery Charger...
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  • How To Charge AGM Batteries In An Enclosed Trailer
    I do have a battery charger for the batteries in your enclosed trailer but I am not aware of a device that uses energy from the rotation of the trailer's wheels for this. The best option we can offer you is the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1225D for a 75 to 200 amp hour battery bank or part # 331-BCDC1240D for a 200+ amp hour battery bank. The Redarc In-Vehicle BCDC Battery Charger uses power from the vehicle's alternator to charge your trailer batteries which...
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Info for this part was:

Employee Mike L
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Adam R
Employee Lindsey S
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