jrfromafar
Adventurer
Can I put a 7 prong pigtail onto the trailer hitch & just take the black 12 v line, hook it up to the pos on my deep cycle battery (with a fuse box) then the white goes to the negative or do I attach to a ground?
How to make a cheap isolated dual-battery setup for $50
- Thread starter evldave
- Start date
dwh
Tail-End Charlie
jrfromafar
Adventurer
dwh
Tail-End Charlie
The 7pin female on the truck will have its white already grounded to the truck chassis. So make a 7pin male, with black and white run directly to the camper battery.
Be advised - the hot (positive) on the 7pin female on the truck might be hot all the time. In other words, it might not switch off when the key is turned off. Check that. You don't want your camper battery tied into the chassis battery full time, but only when the engine is running to charge it.
If its hot all the time, you're going to need to rig a relay. Luckily, this thread explains how to do that.
I would worry about that amp load on that little wire... Yes it will keep the battery charged, but if you were to run a large load with the engine on, that current will be trying to squeeze through a little 20 or 30 amp line. Same as if you deep discharge the battery. It's gonna want a lot more juice during bulk charge than that line can handle.
dwh
Tail-End Charlie
Depends on resistance. If the resistance of the camper battery (and its wire) is less than the resistance of the wire coming from the front of the truck, then the majority of the load will be fed by the battery, not the wire coming from the front.
Worst case - blown fuse.
What it wants and what it gets are two different things. Again, depends on resistance. The resistance of the camper battery + the resistance of the wire coming from the front will determine the amp flow rate.
Worst case - blown fuse.
wwpage66
New member
Got the parts in and finally getting this done. My main hold up was getting a location for the 2nd battery to fit in a 2010 F150. Ended up making a bracket for it. Have it done and now ready to wire it up, had to come in and check the diagram again.
Here is the bracket, back to work.
hopefully a quick finish, one more hardware run...
Here is the bracket, back to work.
hopefully a quick finish, one more hardware run...
coolfeet
Mark Keeler
I have read and reread about a thousand posts on dual battery set ups. Seems like you are answering every thread. Thank you!
My little brain is getting tired. I think I have information constipation. I need to buy the damn battery, isolator, wires, fuses, and get going.
Can you lend a little of your talent in a few words?
Here is my desired output: enough power to run my 60 liter ARB fridge/freezer at night while sleeping. Let's say 12 hours a day max.
I want to install a second battery either inside the 1998 Ford E150 van or on the frame rails. It's a $1000 van. Why spend more on the dual battery set up?! I need money for beer too.
I like the idea of the $50 dual battery set up and maybe upping the ante by $25 and going with some type of smart charger battery isolater ( the big spender in me).
I found the Universal 75 AGM at Batteries Stuff in Grants Pass Oregon for about $160 delivered. They said Lifeline is better, but...way more expensive $259 delivered. The Universal Chinese batteries outsells everything.
I want some 12 volt outlets for powering a Macbook while traveling. Is there such a thing as an adapter that plugs into cigarette style plugs for laptops?
We use our van for camping in the summer. It's not a daily driver. However, we drive it a few times a week to keep the battery charged and to ensure that it runs.
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dwh
Tail-End Charlie
(Answered the rest in the reply to the PM you sent me.)
Sure, there are a ton of 12v cig lighter power adapters for laptops. I have a couple of netbooks - and HP Mini and and Acer Z03
I've got a YD190-474:
http://www.ebay.com/itm/90W-DC-Adap...S-YD190-474-19V-4-74A-5-5-2-5mm-/190833694316
I like it because it's a 90w adapter that can do 4.74 amps at 19v. I cut the cord and put in a plug so I can switch cords for either the HP or the Acer. The HP wants 18v and the Acer 19v, but it works fine on either one. Been using it for years.
They make that same unit with different plugs. You can probably find it with whatever plug you need for your laptop.
This one has the sae specs but cost more:
http://www.amazon.com/Aspire-4520-Z03-Compatible-Adapter-Charger/dp/B00BDOH4SS
coolfeet
Mark Keeler
FLHummer
New member
Got to put my setup to the test on a week long trip at the beginning of the month and it was great. Well, after the first day it was. Found out the first evening that my house battery wasn't getting charged, ended up the solenoid wasn't getting the 12V signal to open up. Found a different location on the fuse box for that lead and everything worked flawlessly after that. One of the most useful mods I have done and this thread made it possible.
coolfeet
Mark Keeler
I looked at the Samlex ACR and it looks easy to install. Can you confirm that I need only 3 connections as per the Samlex ACR PDF instructions?
dwh
Tail-End Charlie
Yea, the Samlex instructions are a bit goofy.
You connect both batteries to the big terminals and a ground to the "minus" terminal (don't forget a 1a fuse in the ground).
That's it and it works on auto.
Optional is the switch control. That goes to the "status" terminal. If you connect the status terminal to hot, it forces the unit to stay on, if you connect the status terminal to ground, it forces it to stay off. You can do that with a single-pole double-throw (center off) switch.
Run the status to the center of the switch, and run the top of the switch to hot, the bottom to ground. In the center position, the ACR will be on auto, with switch up it's forced on, and switch down forced off.
Then you can also add an LED. Connect one lead from the LED to hot, and one to the LED terminal on the ACR. Whenever the ACR solenoid is energized, the LED will be lit up.
coolfeet
Mark Keeler
My battery is arriving on Monday. I decided to go with a LifeLine 80 ah sealed AGM battery as I want it inside my van. It cost 2x the price of a flooded lead acid battery. I am hopeful that it will last longer. Similar Optima batteries were close in price, but the reviews were less than stellar. Costco has flooded group 24 batteries for about $90 including the core.
Ford has battery boxes that mount on the frame and it was going to cost about the same as having the battery inside my van.
I need some assistance in making all the connections as I am not an electrician or mechanic.
What gauge wire should I use and where should I get it? I have no idea how to connect the first red wire to the battery. Can someone send links to eBay or Amazon for the correct parts? I can comp a 6 pack of beer or a few cups of coffee for the best solution through PayPal. This is not in lieu of payment. Rather, a show of gratitude.
DWH here on the Expedition Portal suggested the Samplex ACR. The local stereo shop installs PAC isolator for $90/hour. I found it for PAC for $38 on Amazon. Stereo shop charges $85. They want $400 for the install. DWH says I can easily do it myself.
Can someone suggest automotive circuit breakers? I figure it's probably easier in the long run rather than carrying spare fuses that get lost.
I want to connect the RV battery to an RV battery box with four 12 volt plugs and a quick connect for future solar. Should I drill holes and add the 12 volt plug or buy a box with all the outlets? I am looking at QuickBox sold on Amazon.
If I can do this all myself, I may as well add solar. Anyone suggest a budget friendly 80-100W solar panel and charge controller that can plug right into the battery box via quick connect?
Oh, one final note-I have an old electrical wire repair kit from 1985. What tools should I buy? I want to do everything solderless.
I want to thank everyone in advance especially DWH.
I know all the answers are located somewhere in this forum. I leave for Canada in 17 days and have to get this installed. My wife is taking care of her father out of the country and arrives on June 19. I promised to install over head lights for her in our living room earlier this winter, as well as the dual battery install My repair buddy showed up last night and we cut and drilled holes for everything. We help each other out on repairs. I am the guy who hands the tools and he has all the brains! He does not have time for the dual battery. We were busy all winter remodeling his kitchen and we are out of time. It's crunch time! Between his 9 kids and my 2 boys, we have a circus going on! Ever try to rip out a kitchen with 11 kids? We take our vans to his workshop for automotive repair as it's too dangerous.
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