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Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 50 Amp

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 50 Amp

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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-BCDC1250D 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 - 50 Amp. Battery Charger reviews from real customers.
  • All Info
  • Reviews (66)
  • Q & A (23)
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  • Why etrailer?

Redarc Battery Charger

  • RV/Camper
  • Trailer
  • Battery Charger
  • 12V
  • Redarc
  • Solar Panels to Auxiliary Battery
  • Vehicle Battery to Auxiliary Battery
  • Charges/Maintains
  • 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 greater than 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: 6-1/2" long x 4-3/4" wide x 1-1/2" tall
  • Battery capacity range: greater than 200 amp-hours
  • Maximum charging voltage: 15.3V
  • Output voltage: 12V DC
  • Output power: 750 watts
  • Output current rating (continuous): 50 amps
  • Input current (maximum): 50 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 50 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



BCDC1250D REDARC In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 50 Amp

Item # 331-BCDC1250D

Installation Details 331-BCDC1250D Installation instructions


California residents: click here



Customer Reviews

Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 50 Amp - 331-BCDC1250D

Average Customer Rating:  4.8 out of 5 stars   (65 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-BCDC1250D
by:

I brag about this to other van owners. It gives me more charge from the alternator to my batteries than other brands or products. 40+ amps over about 14 feet of probably six gauge wire from a 130 amp alternator. Stellar tech support!



- 331-BCDC1250D
by:

A year later no issues at all. Solved many issues wish Id bought it earlier and saved a set of batteries.



- 331-BCDC1250D
by:

Sharon was very helpful!



- 331-BCDC1250D
by:

Great product, small form factor, solid construction.



- 331-BCDC1250D
by:



- 331-BCDC1250D
by:

Great



- 331-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


This unit has performed as expected. My batteries are mounted inside a plywood box in the back of my van. All the connections for the Redarc are inside the box so it has a very clean install on the exterior of the box. The two DC switches in the picture allow me to disconnect the input line to the Redarc from the vehicle's electrical system and the second disconnects my Battle Born batteries from everything. I only shut off the system when I take it into the van dealership for maintenance, and that is only precautionary.


Comments
It still works great. In fact, last week I got the solar connected and it worked without a problem.
Bill A - 07/03/2021


- 331-BCDC1225D
by:

Review from a similar BCDC in Battery Charger


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:

Review from a similar BCDC in Battery Charger


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.



- RED96FR
by:

Review from a similar BCDC in Battery Charger


I installed this in a 2017 Oliver Legacy Elite II travel trailer, because I had installed Battle Born lithium batteries and there was no way my truck was going to charge them properly. The actual installation was fairly painless, but I had to run bigger wires from the front of the trailer back to the batteries, which are located over the axles. I get a solid 10.5 amps continuously now, even though my Land Cruiser is only putting out 13.5 volts when connected. It works as advertised and I do recommend it. I took one star off because I think it is over priced, but that is be expected for an Australian import.



- 331-BCDC1225D
by:

Review from a similar BCDC in Battery Charger


"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:

Review from a similar BCDC in Battery Charger


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:

Review from a similar BCDC in Battery Charger


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-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


This is a fantastic unit. Very easy to hook to the camper batteries, using both the solar and alternator charging functionality. Used this without any issues on a 14 day trip. The instruction manual is well written and very clear. No more worries about the state of charge of my batteries even after a long day of driving with the camper because the battery charge level will be greater than 90% when arriving at campsite despite having a refrigerator running in the camper. Will now be able to leave solar panels at home for a short 2 day camping trip. A few times, the battery level was in the 60%-65% charge level and it was charged back to 80+% within a few hours of driving. Just be aware that getting the lead-acid batteries from 90% to 100% takes a much long time because it has to be a constant low current. Purchasing from etrailer was an excellent experience - received it in Canada within 2 days or order.



- 331-BCDC1225D
by:

Review from a similar BCDC in Battery Charger


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:

Review from a similar BCDC in Battery Charger


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-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


This thing is just great. It is rock solid in construction and function. Everywhere I go now in my Arctic Fox slide in and F350, bu two 100AH LiFePo4 batteries are charging at 45 amps along the way. The fact that the Redarc is weather proof allowed me to mount it outside under the camper skirt running my 4awg battery cables along the bottom of the camper right to it.



- 331-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


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.


Comments
Still working great. Sometimes after a long drive our volt meter stays above 12.6 volts full charge until the next morning, something we never saw when using a generator because we never were willing to run that long enough to get a full charge.
Scott R - 07/04/2020


- RED96FR
by:

Review from a similar BCDC in Battery Charger


I'm charging a house battery that powers a 12 volt refrigerator. Very simple install. Not giving this unit a 5 star rating because the 12 volt input and charging wires exiting the unit are 12 gauge wire and they get fairly warm to the touch. The instructions that come with it list 10 gauge wire as the minimum wire size to use to connect it.



- 331-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


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.



- 331-BCDC1225D
by:

Review from a similar BCDC in Battery Charger


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-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


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!


Comments
Redarc unit still performing strong from the day I installed it, no issues. Recently installed Blue tooth battery monitor, no more need to go into the camper and check my digital gauges. During off season camper is stored in the garage connected to solar keep my battery strong and healthy. Pretty awesome feedback from other etrailer customers. Etrailer provided quality products like the Redarc battery charger, still highly recommend doing business with etrailer and zredarc product.
Bill K - 04/15/2020


- 331-BCDC1225D
by:

Review from a similar BCDC in Battery Charger


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:

Review from a similar BCDC in Battery Charger


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.



- 331-BCDC1240D
by:

Review from a similar BCDC in Battery Charger


This battery charger is awesome. Delivers 40 amps of power for my lithium batteries while driving. So far, no problems with my 125 amp alternator using this device. Used it on a two month Utah trip. Would by this again.


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Ask the Experts about this Redarc Battery Charger

  • How To Attach the Redarc In-Vehicle BCDC Battery Charger To the Start Battery
    The Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1250D needs to be installed on the trailer, next to the service/auxiliary batteries. That said, this now means you must run a wire from the Redarc In-Vehicle BCDC Battery Charger to the start battery in your vehicle. The correct size wire to use will vary based on total length as you mentioned. I recommend you go pretty large so you don't have to worry about issues with length or voltage drop. We actually have a kit that will work...
    view full answer...
  • Which Inverter Charger Should I Use For My Keystone Montana RV?
    The yellow wire is the wire that connects to the solar panels. I have attached a detailed wiring diagram and demonstration video for the Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 50 Amp # 331-BCDC1250D. In regard to an inverter/charger with a built-in transfer switch, I recommend going with Go Power Industrial Pure Sine Wave Inverter Charger - 2,000 Watts - 100 Amps - 12V # 34280055 and Installation Kit # 342GPDCKIT4. If you need more than 2,000 watts,...
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  • Solar Input Voltage Range For Redarc In-Vehicle BCDC Battery Charger
    The Redarc In-Vehicle BCDC Battery Charger - Dual Input part # 331-BCDC1250D is only compatible with unregulated 12V nominal solar panels. You can use 2- 12 volt solar panels in series. The solar input voltage must not exceed 32V. I have attached a snip from the instructions for your reference.
    view full answer...
    Image 1 for
  • Can Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D be Used with Lithium Batteries
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D that you referenced is compatible with Lithium batteries like what you are planning on converting to. This can also accept charge inputs from an alternator and solar panel so it will work well in that regard as well.
    view full answer...
  • Redarc BCDC Battery not Getting Enough Charge from Car Battery to Last More than Two Days
    If you are not getting enough power from your vehicle's battery to charge your Redarc In-Vehicle Battery, part # 331-BCDC1250D, for very long, you can supplement the power going into the RV battery with a solar panel like the Go Power Solar Flex, part # 34272630. We have an extensive selection here that runs the gamut of price and wattage. I've linked to this list for you. Also, be sure to check the manual linked below for the Redarc. Page 12 has a table for cable sizing. If you do...
    view full answer...
  • Can Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D Charge 100 AH Battery Bank
    Yes the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D could charge a bank of 7 100 amp-hour batteries like you have. It would be a matter of wiring up the charger to the battery bank in parallel so that the charger charges all of them.
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  • How To Charge Lithium Ion Batteries While Driving and Hooked Up to 110 Volt Power
    In order to charge two lithium-ion batteries while you drive you really only have one option which is to use the vehicle's alternator. In order to pull current from the vehicle's alternator and apply the correct charge profile you need a pretty sophisticated device, the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1250D which will make sure you don't undercharge the tow vehicle's battery and overcharge the trailer's batteries or vice versa. Then, in order to charge the batteries...
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  • Solar Panel Open Circuit Voltage For Redarc BCDC Battery Charger
    Based on my research a 12 volt panel doesn’t put out 12 volts but it produces enough voltage to charge a 12 volt battery. It produces around 18 volts and has an open circuit voltage, without a load, of 21 volts. So without a controller, you will only be able to use 1 panel. To use more than one panel you will need a controller like the Furrion MPPT Solar Charge Controller - 50 Amp - 12V and 24V # FSCC60PWBBL which works with panel combinations up to 600 watts.
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  • Will the Redarc In-Vehicle Battery Charger Charge the Start Battery While Trailer Is Detached
    I spoke with Redarc about the Redarc In-Vehicle BCDC Battery Charger part # 331-BCDC1250D and they informed me that the unit would not charge the start battery, only the auxiliary battery bank in the trailer. That said, the unit would not let the auxiliary battery bank pull enough power from the start battery in order to create any issues with starting the vehicle so there should be no worries here. If needed, you could also use a small solar panel just to keep the start battery topped...
    view full answer...
  • Recommended Wire Gauge for Redarc 331-BCDC1250D In-Vehicle BCDC Battery Charger
    It's recommended you place the charger as close to the battery being charged as is possible. According to my contact at Redarc, if the wire length will be 3-16 feet, 6 gauge cable is recommended. If that distance is greater than that, say between 16 and 30 feet, 4 gauge cable is recommended. Per Redarc, if you stay within those guidelines, the voltage drop wouldn't be an issue. I've linked to a product demonstration video featuring the Redarc # 331-BCDC1250D charger.
    view full answer...
    Image 1 for
  • Solution For Powering An ARB Fridge While Dry Camping
    I recommend the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D, the main reason for this is controlled current draw. By using a BCDC, this charge current will be regulated to a specific amount. The current draw from the starting battery would be limited to 55-58amps. The BCDC should be mounted no further than 5 feet from the batteries it is charging. This ensure the output voltage is not effected by voltage drop. Some other steps to consider include changing your battery...
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  • What Gauge Is Each Wire On The Redarc 331-BCDC1250D Battery Charger?
    The gauges of the wiring harness on the Redarc # 331-BCDC1250D are as follows: The high power wires are 8 gauge – yellow, brown, black, red. Use 6 gauge wire for the high power cable extensions if you are only extending up to 16 feet. However, if you are going to have high power cables ran 16 feet or more, it is recommended to use 4 gauge for the extensions to reduce voltage drop. The referencing wires (no heavy load) are 16 gauge – orange, blue, green. I have attached a demonstration...
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  • Could Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D be Used with Battery Bank
    Yes you can use the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D to charge battery banks like you have. Since this maximizes the charging it would improve the charging speed.
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  • Recommended Battery Charger for Dump Trailer
    There's a few different options you have for charging your batteries on your dump trailer. If you are wanting to charge the batteries while you are driving I recommend the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D will not only charge your batteries but it will increase the charging amps so that it charges your batteries faster. If you want the ability to run your dump trailer off of your truck if your trailer batteries have been used, I would pick up # BDW20207. This kit...
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  • Redarc BCDC Charger Compatibility with Magnum Energy Inverter
    The Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1250D that you referenced would work great with all of the components you mentioned. The 270 amp alternator and the Magum Energy MS2812 Inverter.
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  • Recommended Redarc DC to DC Battery Charger For Single Group 24 Battery On Work Trailer
    For your Trailer I recommend the Redarc In-Vehicle BCDC Battery Charger # RED96FR as it is what you should be using for your single battery. This will provide 12 amps of charge from a 12 amp current which you should be able to get from your 7-way charge line already on your tow vehicle. Your single Group 24 Battery # BRW34FR will have an amp hour rating of around 75. This means that in good condition it will put out 75 amps of 12 volt power for 1 hour. The Redarc In-Vehicle BCDC Battery...
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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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  • How to Pick Out Redarc DC to DC Battery Charger for 450 Amp Hour Battery Bank
    The only difference between the Redarc # 331-BCDC1240D and # 331-BCDC1250D is the maximum output rating of 40 amps and 50 amps, respectively. Both of these charging units are designed for battery banks above 200 amp-hours. The difference in output means that the 50 amp version will charge your battery from dead to 100% charge faster than the 40 amp version. Overall, I recommend the 50 amp version as it would be able to charge a dead battery faster than the 40 amp version.
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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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  • Does 12-V Trailer Connector Circuit at 7-way on 2017 Ford F350 Remain Active With Vehicle Running
    Once the trailer is plugged in and the brake pedal is depressed, the 12-volt power circuit on the trailer connector will become active, and can be used for whatever purposes you wish. Keep in mind that this circuit can maintain a trailer battery, but it won't have the available grunt to charge a discharged battery. To fully charge the battery while the tow vehicle is running, you'll need a DC to DC charger like # 331-BCDC1240D for a 40 amp or # 331-BCDC1250D for a 50 amp charger. If you...
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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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  • Which MIDI Fuses Are Needed to Install Redarc BCDC 331-BCDC1250D DC to DC Battery Charger
    You'd need # 331-FK60 60A MIDI fuses at the positive connections to the start and auxiliary battery as mentioned on page 10 of the instructions for the Redarc # 331-BCDC1250D DC to DC battery charger (see provided link). The fuses are included with the # e56ZR installation kit you'd looked at.
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  • Trailer Side Wire Functions for 6- and 7-Way Connectors for a Dump Trailer
    It sounds like you have either a 6-Way or 7-Way connector. I have included a couple of pictures that show the functions of 6- and 7-Way connectors for you. Basically, the 12 volt circuit from the vehicle connector will pass through to the trailer side connector and you can attach the wire associated with that circuit directly to the positive terminal of the first battery. Keep in mind that when 2 batteries are hooked together like you have it takes longer for the second battery to get...
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