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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp

Item # 331-BCDC1240D

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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 800-298-8924 to order Redarc battery chargers part number 331-BCDC1240D 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 - 40 Amp. Battery Chargers reviews from real customers.
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  • Reviews (19)
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Redarc Battery Chargers - 331-BCDC1240D

  • Redarc
  • Battery Charger
  • Vehicle Battery to Auxiliary Battery
  • RV/Camper
  • Trailer
  • DC to DC
  • Charges/Maintains
  • 12V
  • 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 larger battery banks rated 200 amp-hours and higher
  • 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-FK60 - 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 led acid, calcium, and Lithium ion (LiFePO4) batteries
  • Overall dimensions: 6" long x 4-3/4" wide x 1-1/2" tall
  • Battery capacity range: 200 amp-hours and greater
  • Maximum charging voltage: 15.3V
  • Output voltage: 12V DC
  • Output power: 600 watts
  • Output current rating (continuous): 40 amps
  • Input current (maximum): 40 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 40 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-FK60 - 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



BCDC1240D REDARC In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp



331-BCDC1240D Installation InstructionsInstallation Details 331-BCDC1240D Installation instructions


California residents: click here


Video of Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp


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




Video Transcript for Redarc Battery Chargers - Battery Charger - 331-BCDC1240D Review

Speaker 1: Today we're going to take a look at the Redarc 40 amp dual input multi stage, 12 volt to 24 volt, DC to DC in-vehicle battery charger. This DC to DC battery charger will draw power from your vehicle, provides power to an auxiliary battery on your trailer or RV. It's ideal for battery bank traded 200 amp powers and higher. It does uses a multi-stage charging algorithm, to ensure a complete charge or your secondary battery, without over charging. It has a boost stage, which provides a constant charge, while monitoring auxiliary battery voltage, and it has an absorption stage, which keeps your voltage stable to avoid overcharging, while bringing the battery up to 100% charge. Finally, has a float state, which maintains your charge on your auxiliary battery.It is a dual input device.

It can pull power from two sources. Can use the red wire and connect it to 12 volt or 24 volt start battery. Use the yellow wire and connect it to solar panels. Now, the solar panels we do sell separately on our website. Since this is solar power capable, the charge will automatically draw power from the panels before tapping into your vehicle battery.

It does use a built-in MPPT regulator, to ensure most efficient power transfer possible in all conditions.This is a fully sealed construction. It's a fan free operation, to ensure durable performance under harsh conditions. It is tested to endure operation in temperatures as high as 176 degrees fahrenheit, and this will protect your sensitive electronics from water, dust and shock. Does use fault recognition technology, prevents damage to your batteries from voltage spike, overheating and reverse polarity connection.The battery isolator function prevents the charger from pulling power from your start battery when the vehicle is off. Does have multiple mounting options for convenient installation.

You can secure this unit in the cab of your vehicle, along a chassis frame rail, or even in the engine compartment.The cables, fuses and connectors, we do separately on our website. To install this, it's Part Number 331-FK60. This part is made in Australia. Few specs again, the application is for 12 volt or 24 volt vehicle systems, with standard or smart alternators. The battery types supported are AGM, gel, standard lead acid, calcium and lithium ion.

Battery capacity range, 200 amp hours and greater. Maximum charging voltage is 1523 volts. Output voltage, 12 volts DC. Output power is 600 watts. Output current rating continuous is 40 amps and input current max is 40 amps. Comes with a nice, detailed instruction manual in how it operates and how to install it.The last thing I want to give you the overall dimensions on it. It's a very small unit. Overall length, 6'-1/2". Overall width, including the mounting brackets is going to be right at 4-3/4", and overall height is 1-1/2" tall. That should do it for the review on the Redarc 40 amp dual input multi stage, 12 volt or 24 volt DC to DC in-vehicle battery charger.


Customer Reviews

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp - 331-BCDC1240D

Average Customer Rating:  4.9 out of 5 stars   (19 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-BCDC1240D
by:

Install took a little time. You will need a hydraulic connector press and then you will have to solder connectors. I ordered connectors off of the internet 637835



- 331-BCDC1240D
by:

One year later: Installed this to charge 2 - 100Ah Lithium Batteries from 160 Amp Alternator - It does a much better job than just the alternator itself - the boost speeds up charging by a x4 factor - worth every penny. Highly recommend - easy install with clear instructions. 602885



- 331-BCDC1240D
by:

Excellent product, easy install. If you want the option to charge and maintain an Auxiliary Battery from main battery or solar, this is an excellent compact unit. Installed this unit a year ago for a Four wheel camper. Maintain a charge on the road and camping off road, still working strong, no longer need to charge battery in the off season using solar switching, awesome for camping and maintain healthy battery. Thanks to etrailer for offering Redarc products, ease online ordering, support and on time delivery, outstanding. Highly recommend doing business with etrailer and buying this product and the Bulldog connectors! 628464



- 331-BCDC1240D
by:

Brilliant product! Charges trailer battery while you drive! When full-timing (almost always dry camping) we frequently found it necessary to run the generator *after* arriving at a new campsite because the “charge” line on the 7 blade RV connector delivered so little power. This fixes that: It delivers a full 40 amps to our two ~100AH flooded batteries (Walmart 29DC), which will take them from 50% to 80+% charge in less than 2 hours, our usual travel time between sites, eliminating the need to run the generator completely on most days (and we don’t skimp much on electricity, using the microwave and watching movies most evenings and a forced air heater all night). A few tips: 1) It draws 43 amps from the vehicle, so you really need the 4 awg wire to the trailer and a heavy-duty disconnect (we used a 150 amp which works well with 4 awg). 2) At full draw the vehicle battery was at 12.8 volts at idle, so it’s right at the limit: You definitely don’t want to be drawing down the starting battery. This is on a Nissan Frontier with a 130 amp alternator, meaning you also wouldn’t want to use it on a vehicle with a smaller alternator unless you’re sure you’ll always be running it above idle and/or without lights/AC/etc. on. 3) A hydraulic crimper would of course be preferred but I used a hammer crimper which worked fine. Just be sure you shrink-tube the connection since hammer crimpers can penetrate the lugs. To get full thickness into the lugs, either fold the wire in half, run the wires (8 awg from the unit, 4 awg from the line) past each other when making a butt splice, or half-fill the lug with strands cut from your 4 awg wire and then push the line in around them. I connected it to the lugs on our inverter since there were already 4 awg lines running from that to the batteries. 4) Hookup was easy, running a 4 awg line from the truck battery to the bed not so much. I fused it of course, but it’s definitely not something you want to chafe or real drama could ensue. The maximum usable distance from the vehicle to the unit is much longer than what the manual says (e.g., if your batteries are in the back of your trailer), but you must ensure that it’s at least 4 awg all the way. Using vehicle and trailer chassis grounds are fine: You don’t need to run a negative line except for a short one between the truck and trailer frames (i.e., don’t use the hitch as a ground connection). 5) Be sure you disconnect the charging line on the trailer plug. The manual doesn’t mention this, but if you don’t you’ll lose charging capacity because some of your power will feed back through that wire. 6) I used the 15V setting to maximize charging time efficiency. It quickly trips back to 13.6 volts once reaching that (much quicker than our equalizing multistage charger, for example) so no worries about overcharging. With the standard 14.6 volt cutoff you’re giving up significant amount of charging if you only drive a short time. 7) It’s 93% efficient (according to tech support) but does run pretty warm when at full output for a long time. It should be installed in area with ventilation and definitely not in an engine compartment. 8) Redarc tech support was awesome when I had questions about the installation. 666008



- 331-BCDC1240D
by:

I installed a BCDC1240D (with optional fuse kit) in my Winnebago Revel (Mercedes Sprinter). The instructions are clear and I was able to figure out the wiring requirements pretty easily. I wired the Redarc with a switch to change between profile C (winter) and B (summer). The batteries are mounted below the vehicle so I probably need profile B at higher temperatures in the summer. I have included a picture of the Redarc installed in the passenger's seat pedestal in the van. Most of the wiring in there is Mercedes and Winnebago. You should be able to identify the Redarc (bottom center), and the two fuse holders (fuses not yet install) near the blue tape. 583167



- 331-BCDC1240D
by:

I have 300ah Lifepo4 batteries from Renogy.. 300 watt solar.. this unit will charge via solar or vehicle.. one or the other .. whichever has more power.. I see the lights on and see it working.. the reason I like this unit is because my batteries are only being charged from one charging source. This is safer and will improve battery life. I just wish it could have a battery and voltage meter.. I guess I need to buy a battery monitor.. This is almost the perfect device.. it needs a display for battery life and voltage.. I would love to know what it is doing. 586562



- 331-BCDC1240D
by:

Have not installed the Redarc in my camper yet, but really appreciated the quick turnaround on my order. Quick shipping was better than Amazon. 728803



- 331-BCDC1240D
by:

Is working great in my Silverado to keep auxiliary battery charged for the bed accessories. Just added a solar suitcase to it for charging and using electrical without engine. Thinking about installing the jump circuit just for safety 646758



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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 677741



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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”. 594415



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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. 590921



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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. 601615



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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. 508790



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


Used for full time suv living and traveling. Kept my lithium battery and fridge up and running with solar as well. Awesome product. 727905



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


Great product. 686891



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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. 634086



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


Product has worked as stated. 5 stars! 629151



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


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.) 565968



- 331-BCDC1225D
by:

Review from a similar Redarc BCDC in Battery Chargers


Quick shipping, Haven’t hooked it up ye t. 469810


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Ask the Experts about this Redarc Battery Chargers

Do you have a question about this Battery Charger?


  • 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...
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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,...
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  • Recommended Truck Camper Dual Battery Charging System
  • The NOCO Genius Mini On-Board Battery Charger - AC to DC - 2-Bank - 8 Amp # 329-GENM2 will work for a shore power to batter power charger for batteries up to 120 amp hours. If your batteries are larger then you will need the NOCO Genius On-Board Battery Charger - AC to DC - 4-Bank - 40 Amp - 12V # 329-GEN4 to charge batteries up to 230 amp hours. Most truck campers will instead use a DC to DC charger for the camper batteries. If your batteries are under 200 amp hours, I recommend the...
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  • Why is Relay Kit for Redarc In-Vehicle BCDC Battery Charger Needed for Smart Alternator
  • The 60-Amp Relay Kit for Redarc In-Vehicle BCDC Battery Charger # 331-RK1260 is needed - but not necessarily required - for use with the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D (25 amp) or # 331-BCDC1240D (40 amp) with a smart alternator because those chargers require starter battery voltage and running an ignition feed to the charger can be difficult. Your example of a long run to a trailer is on the money and exactly what it would be needed for. I have added a cut out...
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  • The Progressive Dynamics PD9100 Series Inteli-Power Converter - Lithium - 12 Volts - 60 Amps # PD9160ALV will allow up to 60 amps power draw. It sounds like you are able to pull more, so I recommend upgrading to the 80 amp # PD9180ALV. This will charge your batteries in about 2 hours give or take. If you want to charge your battery while driving, I recommend the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp # 331-BCDC1240D along with the 60-Amp...
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  • Recommended Mounting Location for Redarc DC to DC Battery Charger # BCDC1225D
  • It is advised to install the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D or # 331-BCDC1225D in your trailer and not your truck. I've attached videos of this installation to assist. Specifically we put this product in the front storage compartment of the RV to be close to the wiring that connects to the vehicle and also the trailer battery because the unit installs between those two components. The In-Vehicle refers to the trailer and not the tow vehicle so you can use the...
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  • Recommendation for Charging a Lithium Battery Bank From a 2009 Ram 3500 Diesel Tow Vehicle
  • The Tow Ready Battery Isolation Solenoid # TR118665 along with 00 gauge wire and Pollak Single-Pole, Round Pin Trailer Wiring Socket # PK11851 along with # PK11852 will allow you a great connection for charging your battery. I also recommend putting a 40 amp circuit breaker # 9510 in line to protect your system. The issue is it will not amplify your charge so you will still be limited to the 2-3 amps charging above what your truck uses from your alternator. For a better option, I recommend...
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  • How to Charge Trailer Batteries with the Vehicle's Alternator and Shore Power
  • I do have options for you but the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1240D would not accept AC current from shore power and then use that to charge your two AGM batteries while disconnected from the tow vehicle. The Redarc In-Vehicle BCDC Battery Charger would still be needed while driving but when parked you would need to install a power converter to charge the batteries using shore power. The correct power converter will vary depending on the A/h of your batteries...
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  • Recommended Trailer Battery Charging System for Enclosed Motorcycle Trailer for Tools and Mattress
  • You can absolutely use a battery in your trailer to do all the things you desire. You will simply want to get a deep cycle battery and get the amp hour rating you desire. The CTEK D250S Dual Battery Charger 12V- 20a, 5 step, Heavy Duty# CTEK40186 along with the discontinued CTEK SmartPass Energy Management Unit for CTEK D250S DUAL Battery Charger CTEK56676 are a great combination for that as the D250S alone will not work well on the high-capacity deep cell batteries. Instead...
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  • Recommended In-Vehicle Battery Charger for House Battery on Ford Transit
  • The Redarc Smart Start Battery Isolator # 331-SBI212D referenced in your question will install between your Ford Transit's start battery and house battery. This will essentially pull power from either battery in an effort to keep both charged. It can potentially charge the house battery to 100%, but this is dependent on the start battery being completely charged as well, which likely won't be the case for the most part. This particular product isn't so much a standard battery charger, but...
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  • What Plug Fits the 337TC1002 Horizontal 2 Pin Connector?
  • To fit the Buyer's Products 2 Pin Horizontal Socket # 337TC1002 you can use the Buyer's Products # 337TC2002 which is a 2 Horizontal Pin plug. This plug and socket require 6 gauge wiring and can carry up to 40amps. As an aside, if you're spending a lot of time dry camping like you mentioned in your email, you may want to have a look at the Redarc In-Vehicle BCDC Dual Input Battery Charger # 331-BCDC1240D which is ideal for battery banks rated 200 amp hours or higher. This will allow...
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  • Recommended Wiring for RedArc BCDC Charger Used for Auxiliary Battery to Power Inverter
  • To connect your Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp # 331-BCDC1240D, you will need the 60-Amp MIDI Fuse Kit for Redarc In-Vehicle 40-Amp BCDC Battery Charger # 331-FK60. This will protect your vehicle and battery from potentially damaging overcurrent from short circuits or overloads. You will run the Red Wire from your RedArc unit to the fuse, and then from the fuse to the positive battery terminal on your vehicle start battery. I've...
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  • Compatibility of DC to DC Charging Trailer Batteries While Operating Refrigerator Off Inverter
  • Yes. The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D is designed to allow you to run your inverter and other components while towing. If you need more than the 25 amps and 375 watts for your application, then I recommend the 40 amp # 331-BCDC1240D which will give you 600 watts.
    view full answer...

  • Charging Trailer Batteries While Towing Using the Alternator in a 2016 Ford F-150
  • The problem with charging trailer mounted batteries is that vehicle alternators and the wiring going through, say, a 7-Way trailer connector cannot push back the amperage required to charge up the batteries (or it would take an extremely long time). At best they can maintain the charge level in most cases. But there is a solution to that issue and it is actually similar to what you have suggested. What you need is a DC to DC charger. We do have one rated at 40 amps, # 331-BCDC1240D,...
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  • Will RedArc Battery Charger Work With Solar Panel and 7-Way to Charge Camper Battery
  • I reached out to a representative of Redarc who told me that the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D is the correct charger for your application and there will be no interference or conflict with the charges the battery is getting from the solar set up. The input to the BCDC Charger will be sourced from your F-250's start battery (which is going to be on the passenger's side of your 2-battery set-up) with the 60-Amp MIDI Fuse Kit for Redarc In-Vehicle 40-Amp BCDC Battery...
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  • 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...
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  • Can 55 amp Lithium Converter for WFCO RV Power Centers be Used for Charging Batteries 10 Away
  • The Lithium Converter for WFCO RV Power Centers # PD4655LIV has a BMS (battery management system) which balances the cell voltage and senses the battery voltage to give you the best charge out there. This unit will charge your lithium batteries but it won't be able to charge them to 100% capacity. For that you need to add the Redarc 40 amp BCDC Battery Charger # 331-BCDC1240D. This has a smart unit inside that actually boosts the voltage and sense when your batteries are at 100%.
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  • DC to DC Charger and Solar Panels for Best Charging of Multiple Batteries
  • The CTEK D250S Dual Battery Charger 12V- 20a, 5 step, Heavy Duty # CTEK40186 has a maximum output of 20 amps. When used with the (discontinued) CTEK SmartPass Energy Management Unit for CTEK D250S DUAL Battery Charger CTEK56676, my contact at CTEK said it has a max amperage output of 120 amps not the 80 they have previously stated in the past. This combination will allow 14.4 volts and 120 amps to pass to your batteries whether using solar or alternator. He also stated that you can...
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  • Comparing CTEK D250S and SmartPass vs Redarc DC-DC Charger
  • I reached out to my contact at CTEK and the CTEK D250S Dual Battery Charger 12V- 20a, 5 step, Heavy Duty # CTEK40186 does utilize the Maximum Power Point Tracker (MPPT) as well. When partnered with the (discontinued) Smartpass CTEK56676 you will be able to run your fridge/freezer as you stated. The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D will also be able to accomplish this so it is a better option for this application. You will also need the fuse kit # 331-FK60 for this...
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  • Best Way to Add 7-Way Connector on 2009 Toyota FJ Cruiser for 12V Power to Trailer
  • The best solution for your application is to install the Tekonsha T-One # 118405 on your 2009 Toyota FJ Cruiser for your standard trailer lights and then add the Wiring Kit # ETBC7L which comes with everything you need to convert the 4-Way to a 4-Way/7-Way and add the 12V function. Please note that as power runs along that line there will be some voltage drop which will likely keep your batteries from charging completely. To help remedy this I recommend using the Redarc In-Vehicle BCDC...
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  • 12 Volt 5th Wheel Trailer Battery Charge While Towing
  • The pin at the 1 o'clock position is the 12V power used to provide the "maintenance" charge to your battery. The issue you found with your F-250 is the same as what you will find with all vehicles. The charge provided to your trailer battery is minimal when driving because even though it is 12V, it is only about 2-4 amps. This is because your vehicle alternator is generating around 14 amps when your truck is running and only the extra not being used to maintain your truck's electrical...
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  • Trailer Battery Charger and Power Inverter for Coleman Pop-Up Camper with Deep Cycle Battery
  • For a DC battery charger to maintain your trailer's deep-cycle battery I suggest the Redarc In-Vehicle BCDC 40-Amp Battery Charger # 331-BCDC1240D. This unit installs in your vehicle and delivers charging and maintenance current to keep your trailer battery topped off. This is made for high-capacity batteries of 200 amp-hours and above. It also allows the option to add a solar panel to provide a secondary power input. You will also need MIDI Fuse Kit # 331-FK60. A lower-price option...
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  • Can The Redarc Charger Feedback Into The Vehicle's Electrical System
  • I contacted Redarc and the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC part # 331-BCDC1225D and 40 Amp version part # 331-BCDC1240D is designed so the current only flows in one direction. The battery isolator also protects the vehicle's battery from draining.
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  • Does Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D Require Shore Power
  • The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D that you referenced does not have a way to run AC/shore power to it. It takes all DC, 12-volt style power sources.
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  • Recommended Vehicle To Trailer DC to DC Charger for Multiple Trailer Batteries
  • Your auxiliary power wire gauge at your 7-way along with the # CTEK40186 will be sufficient to charge your trailer batteries. The CTEK D250S Dual Battery Charger # CTEK40186 will amplify the signal from your auxiliary power to boost it to 20 amps versus the 2-3 amps of a system without the CTEK unit. Changing your gauge of wire to 8 and adding the # DL24086 connections will help slightly but if you are wanting to charge multiple batteries well and more quickly/efficiently, you really...
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  • How to Have Power When Camping Off-Grid in a 1981 Skamper Popup
  • If you are wanting to charge your phones and other electronics without having to plug into a station you can definitely use some batteries to do so. The best solution for keeping your battery charged is to use a battery charger like the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1240D. This can draw power off of your tow vehicle battery while traveling and as well as a solar panel. We have a variety of solar panels to choose from depending on how much power you plan on using....
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Info for this part was:

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