Dual battery help! (1 Viewer)

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MrCWineMan

SILVER Star
Joined
Oct 3, 2015
Threads
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Location
Colorado Springs, CO
Website
www.tinsheets.com
So here's the deal, I've been reading for like three days straight about varied dual battery set ups on 200's, and other cars, on Mud, expedition portal, anywhere really, and like I used to say in the coaching world, I'm suffering from paralysis by analysis. So here is my particular set of issues to resolve.

1. I need this the be in the rig (2016 200) pretty promptly, as I need to power a fridge 24 hours a day on a trip leaving a week from Tuesday morning.

2. I can't have Slee do it because they are booking a month out right now

3. I really don't think I need a display on battery condition, and if I do I would love it to be in the back in the drawer set up.

4. I don't want to spend a gargantuan amount on this.

Options I've considered:

1.Going with the Add-A-Batt from Blue Sea, install does not look all that complicated, hardest part is buying a hydraulic crimper that I may never use again.

2. Buying the slee IBS system when I'm up in Golden Monday and making the install happen myself. Couple of questions here- is there enough cable for the monitor to make it into the drawers? How difficult is running wires in a 200 v. The old 60 series?

3. Since it's just a fridge, what about a portable power pack from people like Goal Zero?

4. If I do run a dual set up (which is likely) should I run 4 gauge back to the drawers and put in a fuse box there, or just run accessories cable back from the engine compartment and keep the aux fuse box in the engine bay?

Am I missing any details here that should be taken into account?
 
What fridge are you using and how long will the engine be off when using the fidge?
 
I've run the same fridge for about 4 years now off of a 27F battery, in both my FJ and 200 Series. You will have no problem tapping the always on leads (like the ARB fridge plug kit) right off you starting battery. You are not going to kill the battery with a simple overnight, even if it is 95 degrees F at night.

No need for a dual battery with your situation. For piece of mind you can get a small jump starter (I've never used mine for myself, so they are good for others)
 
Given your time constraints I'd recommend the Goal Zero or Anker system if you don't want to risk running off of the primary battery. The fridge should have mechanisms in place to prevent completely draining your battery.

I went the Blue Sea route and simplified the wiring by not using the remote override switch and it's performed flawlessly. I ran 6 awg wiring to the rear and in hindsight I would have run even larger wiring under the vehicle to the rear for potential use of OBA and/or a charging point for solar.
 
You don't need the full add-a-battery kit. All you need is the 7610 ACR that's part of the kit. Fuse all the wires leaving the positive terminal of the batteries and you'll have a safe and automatic system.

4 ga is heavy wiring all the way to the rear assuming the house battery remains under the hood. For just a fridge and similar 8 ga will be plenty and much easier to run back there.

To satisfy your criteria, especially #4 the Blue Sea 7610 is awesome, use it to tie the batteries together with #2 cable. Run 8 ga to the rear fused with a 60 amp fuse to power a rear fuse panel and run your circuits from there.

I don't like those power box electroglitter things like GoalZero and ArcPac. Way too expensive for what they are.

But if you want quick and dirty, just run a fused 10 ga wire direct from the battery to the rear. It will power a fridge just fine.
 
I've run the same fridge for about 4 years now off of a 27F battery, in both my FJ and 200 Series. You will have no problem tapping the always on leads (like the ARB fridge plug kit) right off you starting battery. You are not going to kill the battery with a simple overnight, even if it is 95 degrees F at night.

No need for a dual battery with your situation. For piece of mind you can get a small jump starter (I've never used mine for myself, so they are good for others)


▲THIS▲ You can make it overnight with a 27F no problem no need for a dual battery or any other stuff. Get the ARB fridge wiring kit to make the wiring thing simple. An Antigravity jump box is your insurance policy IF you ever have a problem.

Keep it simple
 
▲THIS▲ You can make it overnight with a 27F no problem no need for a dual battery or any other stuff. Get the ARB fridge wiring kit to make the wiring thing simple. An Antigravity jump box is your insurance policy IF you ever have a problem.

Keep it simple

That is actually what I did in my FJ60 is just pull the wire right off the primary battery, I just haven't had it run overnight yet.
 
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I agree with the above posts that easiest is to run a 10AWG hot wire (fused at the battery) back to the rear and plug in the fridge. And a 27F battery will certainly run that overnight. However, the specs of the ARB50 show a draw of 2.3 amps when running and a small power draw when not running (but plugged in). If you are engine off for 14 hours overnight each day and the ARB is at 75% duty cycle (it is summer!), you’ll be pulling about 24-28 Ah out of the battery. With that much discharge repeated everyday on a longer trip, I suggest you at least get a deep cycle 27F battery because it would be better able to handle that kind of cycling compared to a starting battery. Even deep cycle batteries last longest if not discharged over 50%. Best overall is a dual battery set up with the house battery being deep cycle. Whether that’s worth it depends on long-term needs and things you might want to run in addition to the fridge.

The Blue Seas system is not complicated to install (once you have the 2nd battery in place), and you can buy pre-made cables in whatever lengths you need so you don't have to get the "never use again" crimper.
 
I agree with the above posts that easiest is to run a 10AWG hot wire (fused at the battery) back to the rear and plug in the fridge. And a 27F battery will certainly run that overnight. However, the specs of the ARB50 show a draw of 2.3 amps when running and a small power draw when not running (but plugged in). If you are engine off for 14 hours overnight each day and the ARB is at 75% duty cycle (it is summer!), you’ll be pulling about 24-28 Ah out of the battery. With that much discharge repeated everyday on a longer trip, I suggest you at least get a deep cycle 27F battery because it would be better able to handle that kind of cycling compared to a starting battery. Even deep cycle batteries last longest if not discharged over 50%. Best overall is a dual battery set up with the house battery being deep cycle. Whether that’s worth it depends on long-term needs and things you might want to run in addition to the fridge.

The Blue Seas system is not complicated to install (once you have the 2nd battery in place), and you can buy pre-made cables in whatever lengths you need so you don't have to get the "never use again" crimper.

I agree with this. Even with a jump pack I'd be weary of running a fridge off of the main battery all night. I'm sure it can be done (as noted above) but having a flat battery in the morning would be on my mind all night. Even running the SiriusXM while I setup camp gave me the willys (before I installed the massive 110aH 2nd battery)

As for running the main + to the rear, it's fairly easy. I went in through the passenger kick panel, under the door sills, to inside the rear cargo area. There's plenty of space in that route. I ran both a + and - 2AWG since my inverter/charger required a direct battery -. The only issue is the large trim piece that covers the tire hump/cargo area, if you already have drawers installed it can be a pain to get a larger gauge wire in there. Still doable. It only took me 15mins to run the wire back there.
 
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I agree with this. Even with a jump pack I'd be weary of running a fridge off of the main battery all night. I'm sure it can be done (as noted above) but having a flat battery in the morning would be on my mind all night. Even running the SiriusXM while I setup camp gave me the willys (before I installed the massive 110aH 2nd battery)

As for running the main + to the rear, it's fairly easy. I went in through the passenger kick panel, under the door sills, to inside the rear cargo area. There's plenty of space in that route. I ran both a + and - 2AWG since my inverter/charger required a direct battery -. The only issue is the large trim piece that covers the tire hump/cargo area, if you already have drawers installed it can be a pain to get a larger gauge wire in there. Still doable. It only took me 15mins to run the wire back there.


I'll admit to mild battery paranoia. I'm not above it. But the part of you post I like the most is the ease of running cables, that makes me happy.
 
I agree with the above posts that easiest is to run a 10AWG hot wire (fused at the battery) back to the rear and plug in the fridge. And a 27F battery will certainly run that overnight. However, the specs of the ARB50 show a draw of 2.3 amps when running and a small power draw when not running (but plugged in). If you are engine off for 14 hours overnight each day and the ARB is at 75% duty cycle (it is summer!), you’ll be pulling about 24-28 Ah out of the battery. With that much discharge repeated everyday on a longer trip, I suggest you at least get a deep cycle 27F battery because it would be better able to handle that kind of cycling compared to a starting battery. Even deep cycle batteries last longest if not discharged over 50%. Best overall is a dual battery set up with the house battery being deep cycle. Whether that’s worth it depends on long-term needs and things you might want to run in addition to the fridge.

The Blue Seas system is not complicated to install (once you have the 2nd battery in place), and you can buy pre-made cables in whatever lengths you need so you don't have to get the "never use again" crimper.

I agree with this. Even with a jump pack I'd be weary of running a fridge off of the main battery all night. I'm sure it can be done (as noted above) but having a flat battery in the morning would be on my mind all night. Even running the SiriusXM while I setup camp gave me the willys (before I installed the massive 110aH 2nd battery)

As for running the main + to the rear, it's fairly easy. I went in through the passenger kick panel, under the door sills, to inside the rear cargo area. There's plenty of space in that route. I ran both a + and - 2AWG since my inverter/charger required a direct battery -. The only issue is the large trim piece that covers the tire hump/cargo area, if you already have drawers installed it can be a pain to get a larger gauge wire in there. Still doable. It only took me 15mins to run the wire back there.

The above if why I dont separate my dual batteries and carry a jump box. I have 160AH total and 80AH at 50% not much chance to end up with dead batteries but if it was to happen I have a jump box. You are better off in the long term to not to separate and get twice the AH than to deplete one battery all the time and keep a charged battery doing nothing. My change was the results from consulting with someone with lots of battery experience and consider an expert.
 
I'll admit to mild battery paranoia. I'm not above it. But the part of you post I like the most is the ease of running cables, that makes me happy.
To kinda add onto the "ease of running wires"
IMG_2947.jpg


Since I have a lot of ideas of what I want in the future, I drilled a hole in seat release trim. It provides a good "right now" spot and will be super cheap to replace later once I know what I want to do with drawers/tie-down plate.

As I don't want to say this next thing without acknowledging that its just what I've experienced, doesn't make it right, because the last thing I want to do is say you won't have a problem, then you do, and are stranded. But... for me, my real world experience from an ARB 50qt and an OEM Toyota 27F battery was that I could run about 2 days in 85-90 degree days with 45-65 degree nights and be just fine to start up the truck. This experience was from two batteries, one about 10 years old, the other about 4 years old, both are still fine, hold a charge and are good under a load test.

If I go past 2 days, I have a cheap goal zero guardian 12v solar charger and attach 40w of solar panels. I've made it 5 days on that with very limited sun. I kept the fridges battery management set to "low," providing plenty of power to start the engine.

My current set up is a Flexopower 80w panel and a Goal Zero lithium 400 (I didn't pay full price), and I run it off that when I know I'll sit for a while. The Lithium 400 is actually just another stepping stone for a large LiFePo4 battery set up I'm working on with Redarc components, but the lithium 400 is mainly my camera/drone/light/tent heater fan power source. But even now, If I stop by noon, and plan on leaving by noon the next day, I keep my fridge on the starting battery, because the draw is so little on what that battery has for capacity.

That's just me, but I think with leaving in a couple days, I would recommend just running off the main battery, and switching things up later, when you have more time. Besides, regardless of single or dual battery, you still need a place to mount the power point and you still need to run wires, so it not loosing too much for right now.
 
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The above if why I dont separate my dual batteries and carry a jump box. I have 160AH total and 80AH at 50% not much chance to end up with dead batteries but if it was to happen I have a jump box. You are better off in the long term to not to separate and get twice the AH than to deplete one battery all the time and keep a charged battery doing nothing. My change was the results from consulting with someone with lots of battery experience and consider an expert.


That's an interesting thought, just add depth to the amp hour pool but cycle both of them as the load and the car chooses. Any dangers to this system? I've heard tell that if you don't have identical batteries that one can drain the other, thoughts?

Did you just do a Slee tray and wire ground to ground and positive to positive? Did you fuse the set up at all?
 
To kinda add onto the "ease of running wires"
View attachment 1481136

Since I have a lot of ideas of what I want in the future, I drilled a hole in seat release trim. It provides a good "right now" spot and will be super cheap to replace later once I know what I want to do with drawers/tie-down plate.

As I don't want to say this next thing without acknowledging that its just what I've experienced, doesn't make it right, because the last thing I want to do it say you won't have a problem, then you do and are stranded. But... for me, my real world experience from a ARB 50qt and a OEM Toyota 27F battery was that I could run about 2 days in 85-90 degree days with 45-65 degree nights and be just fine to start up the truck. If don't this to two batteries, one about 10 years old, the other about 4 years old, both are fine, hold a charge and are good under a load test.

If I go past 2 days, I have a cheap goal zero guardian 12v solar charger and attach 40w of solar panels. I've made it 5 days on that with very limited sun. I kept the fridges battery management set to "low," providing plenty of power to start the engine.

My current set up is a 80w panel and a Goal Zero lithium 400 (I didn't pay full price), and I run it off that when I know I'll sit for a while. The Lithium 400 is actually just another stepping stone for a large LiFePo4 battery set up I'm working on with Redarc components, but the lithium 400 is mainly my camera/drone/light/tent heater fan power source. But even now, If I stop by noon, and plan on leaving by noon the next day, I keep my fridge on the starting battery, because the draw is so little on what that battery has for capacity.

That's just me, but I think with leaving in a couple days, I would recommend just running off the main battery, and switching things up later, when you have more time. Besides, regardless of single or dual battery, you still need a place to mount the power point and you still need to run wires, so it not loosing too much for right now.


Sort of where I'm leaning right now, I have to get the drawers Monday and get them installed, and with that wiring for the fridge, so in many ways, your right, what it connects to in the engine bay does not really matter for this ten day trip as long as it runs the fridge. If it needs to change, change it down the road.
 
That's an interesting thought, just add depth to the amp hour pool but cycle both of them as the load and the car chooses. Any dangers to this system? I've heard tell that if you don't have identical batteries that one can drain the other, thoughts?

Did you just do a Slee tray and wire ground to ground and positive to positive? Did you fuse the set up at all?

This set up is on my 80 series but would apply to any vehicle. I have run this set up for a couple years and recently replaced both batteries. The interesting part was the battery that was the AUX battery first. Because one battery is located in the rear I fuse between the batteries and yes they are in parallel. She said as long as my batteries were new and the same type (AGM in my case) that being used the way I use my set up tied together should not be a problem. The way it was explain to me is they both go down at the same rate and they both charge at the same rate. Time will tell.

As for running your batteries in parallel almost ever diesel manufacture today run dual batteries in this same way from the factory.
 
This set up is on my 80 series but would apply to any vehicle. I have run this set up for a couple years and recently replaced both batteries. The interesting part was the battery that was the AUX battery first. Because one battery is located in the rear I fuse between the batteries and yes they are in parallel. She said as long as my batteries were new and the same type (AGM in my case) that being used the way I use my set up tied together should not be a problem. The way it was explain to me is they both go down at the same rate and they both charge at the same rate. Time will tell.

As for running your batteries in parallel almost ever diesel manufacture today run dual batteries in this same way from the factory.

In the RV world, we parallel batteries all the time. No problem to do this. They should be the same age/capacity/type to avoid giving the charger and batteries problems. Use deep cycle or dual starting/deep cycle, not just starting batteries.
 

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