Redarc BCDC dual battery w/ shore power?

Hey guys. I am currently in the process of getting everything together to install a dual battery setup.

I will be using:
Off Grid Engineering Complete Dual Battery System using a Redarc BCDC 1225D.
A Northstar Group 31 and Group 35 AGM battery
SDHQ (DC Power Engineering) 270 amp high output alternator
VF Tuner adjusted voltage outputs
Renogy 100 Watt panel with the option to have a secondary panel input.

The main question here is, will I be able to run a NOCO Gen 5x2 10 amp charger in conjunction with the BCDC?

I want to be able to plug in charging if the truck is sitting a while OR in most cases, the fact I do not have to drive long distances. Work is only six miles away. I know the solar should help a lot in keeping the batteries topped off, but I like to have all of my bases covered.

I contacted REDARC and they basically told me they did not know if it would work and to contact NOCO.

To me, it seems pretty straightforward. The NOCO would bypass the BCDC since each battery will receive its own input, rather than the BCDC trying to charge both batteries with only 10 amps to work with.

I made this super cool high speed CAD drawing for y'all.

Any input would be greatly appreciated.

Thanks!

 

The BCDC only charges the aux battery, the starter battery gets charged by the alternator. If you hook up a charger to the starting battery it will probably trigger the BCDC to start charging the aux battery while draining the starting battery. I've got the OGE set up and this exact situation happened to me trying to put a charger on the starting battery.

 

If you're going full camper like that, then get a proper RV converter at a minimum. Though if it were me, id save space and run a combined converter/distribution all in one unit.

Look up Progressive Dynamics mighty-mini.


Edit - Also, I disagree with your wiring diagram. I think it needs to be wired as such:

 

I also thought of this arrangement. Input from the solar end would still only charge the aux battery.

 

Did you have one input into the starter battery or leads to both batteries?

 

I just had the charger on the starter battery but noticed the BCDC light up. I reached out to Redarc to see if this was OK and got the following response...
"What you describe is common and something you need to be wary of, if your maintenance charger has an output power rating less than the rated power of the BCDC in question…
Then yes you will end up flattening your main battery…
You see in this instance, when the maintenance charger sees the voltage rise in the start battery (having received charge from your small mains charger) it see this as the vehicle having started and the alternator is providing power…
I would therefore recommend placing a suitably rated ignition controlled solenoid or relay on the input of the BCDC, so the BCDC is isolated/disconnected from the main battery when the ignition is off."

 

Also I'd be very weary of putting a heavier battery in the stock location, after a few years of running a Duralast Platinum group 24 (about 45#) I'm dealing with replacing a cracked core support to the tune of $1,200. I put the blame on the combo of the heavier battery and running the polyurethane radiator support bushings everyone seems to love around here.

 

OK OK. I see what they're saying now. The ignition relay makes a ton of sense. Also makes me wonder if it would negate solar charging when the ignition isn't on.

 

I've had this battery in there for roughly 3 years at this point. Might you have pictures of the damage?

 

I don't think it would, the relay would just be cutting power from the alternator input.

 

Looks like I'll have to inquire on this with redarc. Thank you!

 

https://www.tacomaworld.com/threads/shes-ripping-apart-click-bait-i-knew-it-was-coming.685302/page-8
My story starts at post 156.

 

The main issue I have with tying the batteries together is that they aren't similarity sized. They will be unbalanced when charging, and during discharge your group 35 will drain while your group 31 tries to recharge it, thereby shortening both lifespan and performance.

You really need to keep them on separate circuits.

 

The BCDC does not tie the batteries together, it's a charger for the second battery. It does nothing for the starting battery.

 

I have 2 years on a BcDC charging a battleborn 100ah in my FWC. I have a resetable breaker between the vehicle battery and the BCDC. I disable it when I am using shore power to charge the vehicle battery. Also if I am not using the camper for a while I disable it so any drama with the campers systems wont flatten my vehicle battery. The BCDC will keep the the camper battery healthy using my rooftop solar. In my experience its only during heavy usage or cloudy skies that the trucks alt is needed.

consider getting a portable solar panel to compliment your hard mounted, as you might not want to park your rig in the sun on a hot day.

 

I used anderson connectors to connect mine. Can handle high current and the unit can still be removed easily. If you hard wire it you take the chance of having a hot unshielded wire if you ever have to remove the unit.

 

Exactly what I needed to hear. A relay/breaker. I will use a secondary panel as well!

 

I’m in the same spot. I have 2 g35s and a bcdc. The primary charges with the noco, the fuse pops on the aux. what was the solution (if any?). Did you isolate or wire the noco into the bcdc? I’d like to keep this setup as I work remote and do t drive the truck much. Sounds like an isolator might be the trick on both batteries?

 

Here's my setup.

 

Looks like you went with the original wiring plan but used breakers to isolate when charging yeah?