Off-Grid Engineering Dual Battery System Q&A

Its a really slick setup!

 

I'll have to wait and see how it turns out. I know guys running similar set up as mine and they really only run into charging issues when its really hot in the summer, majority of the time its fine and they're running almost identical set up as me.

 

From descriptions and seeing videos of Australian setups they seem to only run one deep cycle battery for the auxiliary and leave the starter battery as the oem style since it needs cold crank power unlike the auxiliary. Why is that not an acceptable route? I can’t afford to get two batteries and plan on leaving my oem battery as is anyways.

 

Yeah, that's certainly an acceptable route. Just with OGE dual battery systems as is with the MLACR, it is better to have same type. With the redarc, go for it.

 

Different types of batteries have different rates of charge, so within a system, it is best to not mix battery types, but using the redarc DC to DC charger, you can get away with it, because it will condition the voltage for the other battery. If you use the OGE Dual battery system as is with the MLACR, it is best to have same type of construction (AGM versus lead acid versus gel.....)

 

Yes I was mentioning it in relation to the dc-dc. I’m thinking of calling off-grid to get the kit without the mlacr and then get the REDARC. Although I probably only the 2nd tray as well. I assume all the connections should be similar without having looked into in more detail. I’ll look at installs of REDARC before I order to be sure.

 

Would you be able to post pics of your setup? Would help those of of us considering this route.

 

After expo west i would call or email matt as i know some are using his kit with Redarc he might beable to ship with out MLACR or ship with REDARC not sure if thats an option right now.

 

Spoke with him today. He acknowledged the alternator issue and said the dc-dc is a good way to go. While he used to sell a kit for a dc-dc he doesn’t anymore and couldn’t help me beyond selling the 2nd tray and I’d be on my own figuring out parts and wiring needed.

 

good to know! I am currently looking at voltage boosting mods right now.

 

I went the CTEK D250S and SmartPass route with my set-up. Bought it 2 years ago on sale and finally installed 2 weekends ago. Using stock battery and Odyssey Grp 35 as the service battery with Off Grid tray on the passenger side. 80 amp circuit breakers inline to the fuse panel as well as the service battery.


https://www.ctek.com/storage/ma/ee2...l_SmartPass_with_Charger_at_Start_battery.pdf

Ignore the dirty battery...the result of the previous weekend...

Solar ready when I get a panel in the future and ready for shore power hook-up if extended storage is required at at a location with A/C power and the purchase of the M300 as shown in the link.

 

Correct me if I’m wrong, but let’s recap:

MLACR
-want 2 batteries the same type ( although the ml acr doesn’t care it just links them, it’s the batteries themself that will have different internal resistances and kill each other)
-automatic linking when charging
-self jump option
-auto disconnect when voltage drops
-no solar input, however if so late is charging one of the batteries the ml act will sence voltage and connect to charge other one together.
-cost ~150$
-waterproof
- will start charging starting battery first then links to charge both batteries at whatever the alt will put out ~200amps

REDARC
- keeps batteries separate
- no self jump option, can do it but have to add more wire and soloniods ( more weight)
- will fully charge aux battery
-does nothing for starting battery
-solar input but only to aux Battery
-Costs ~ 300$
-rates at 176* so it should not be in the engine bay, operating temp is 190* and during hot weather engine can be over 200*
-waterproof
Can only charge at 40amps. Deeply discharged battery will take a while



Only way I can see the redarc being better is if you run everything off the aux battery bank, and want to kept you regular acid battery for starting.

With the REDARC you will need to add more wireing or carry jumper cables for when your starting battery dies. Will also need to run longer wire to keep controller out of engine bay. If your battery is there then it’s more wire and weight.

 

Great comparison, but are you saying that the alternator issue does not exist? You didn’t address that

 

What alternator issue? If your talking about voltage the batteries need vs what the alternator is putting out?

Here is some of the discussion:

 

Yes, The Whole reason the dcdc charger popped up is because people are saying that the alternator isn’t charging AGM batteries fully.

 

A DC-DC charger has a couple of advantages. It runs a real multiple step charging profile on the battery it's operating on and this charging profile is not dependent on the source, e.g. it won't care if your vehicle charging system is 14.8 V or 13.5 V, it will produce the right voltage on the battery. Second is they are usually temperature compensated so it adjusts.

 

Just want to make sure that 2x NSB-AGM35 Batteries would work in the 2rd gen with your dual battery setup with the passenger tray.

 

I'm interested in this set up too and would be willing to try to figure out how to get these up here. I'm in the Edmonton area. Best I have so far is order and have it all shipped to the MSO at Sweetgrass, then have one pick up all orders. Figure out cost for GST at border, fuel for trip, etc and split three ways.

 

Best get those up to Sweetgrass ASAP. The tariffs are to kick in last day of the month & if it’s made of steel, you’re gonna pay more for sure.

 

I thought tariffs will apply for raw steel and aluminum products? These are finished products.