Ford Powerstroke Diesel Forum banner
1 - 18 of 18 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 ·
I am considering buying a new F250 with diesel. I want to buy it with dual alternators, and then disconnect one so I can use it to power a bank of batteries in the truck bed. How hard is it to reprogram the computer to have it ignore the second alternator? Can anyone tell me the actual codes that need to be changed?
 

·
Premium Member
Joined
·
1,471 Posts
Just leave it connected. Then plug your charge controller into the trailer plug.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #3 ·
Just leave it connected. Then plug your charge controller into the trailer plug.
Thanks, but I don't see how that would work. The batteries in the back are isolated from the ones in the front. I will install a 3000 watt inverter and when I am loading the batteries in the back it will routinely pull well over a hundred amps. I will be draining them before they are recharged.

The normal truck charging profile does not fully charge the batteries, I want a separate regulator set up for deep cycle batteries to manage the ones in the rear.
 

·
Administrator
Joined
·
33,294 Posts
i doubt your going to be able to manage this using the second lower alt from the 6.7
asides from the programming to go back to a single on the truck side u need to find a way to control the lower pcm alternator to operate as a stand alone or replace it all together with a single wire unit or some other internally regulated setup

contact these guys is my recommendation but call them they take forever to reply to emails
 

·
Administrator
Joined
·
33,294 Posts
I will be draining them before they are recharged
typically, not an ideal unless you have a very good BMS

what I would do is run a ACR that will isolate the truck and other batteries until the trucks is running and the truck batteries are over 13,# volts then the accessory batteries charge I do this to charge 4 batteries in my camper
it works well
 

·
Premium Member
Joined
·
1,471 Posts
The normal truck charging profile does not fully charge the batteries...
The charge controller is your separation for the bank. Given that two alt together can't charge your bank, one isn't going to do it either. I agree with the above to get some outfitter help on designing the system, since you are exceeding typical alternator output. Unless you have enough time to charge the bank from the truck system, and you will only pull 100A for a short period of time. You'll need to replace it with a monster one feeding the charge controller...or just get a small generator.

What is your use need? (Amp Hours) How big is the battery bank?
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #7 ·
Thanks GregWork and ZMANN.

I set up two workstations with PCs with dual monitors in an RV. I have 4 6-volt golf cart (GC2 I think) batteries in the back of the truck with an inverter. I added wiring to the RV to allow me to power the trailer while I drive with 120. The golf cart batteries are good because they are designed for a discharge rate of about 75 amps. Two pair in parallel is 150 amps. Just making coffee in a Keurig will draw around 125 amps at 12 volts. Regular deep cycle lead acid batteries are rated to discharge at only 10% of capacity. (A 200 AH battery would only be 20 amps discharge rate)

If the four batteries are fully charged my wife and I can both work for an hour or so (without A/C) before we have to start the truck. This allows us to travel, and still be very in touch with the office. This allows us to work ½ time for longer periods. As long as I can get decent cell reception; I am good.

I started with the Automatic Charge Relay route. When you start the truck the voltage would rise, and the ACR would close at 13.4 volts. However, when you drove for a while the voltage would drop to reduce the load on the engine. and the ACR would drop out. Now the batteries are not being charged at all. This is a write up on the Honda Dual Mode Charging system. I assume Ford follows similar “lower the voltage to save power and the batteries” logic; I know my 2012 Silverado does.


Then I switched to a 500-amp relay to connect the bank to the truck battery. Now the batteries continue to charge, but never get the proper float. I get extended battery life from running a 6-amp dumb charger on the batteries over-night.


I ran 2 #2 cables from the bed to the front, one to ground to the block and the other for power. Most people suggest heavier cables, but I wanted to protect the 146-amp alternator. The voltage drop does not interfere with the inverter when the truck is running and when I am driving, the load is relatively small so the drop doesn’t matter.

I knew I would have to provide my own regulator. After reading your responses, and some research on the web, I am not sure I can use an off the shelf regulator with the alternator that Ford would provide anyway.
 

·
Premium Member
Joined
·
11,999 Posts
I'd suggest buying a truck with a single alternator. Then buy the mounting parts and belt to spin it on the truck. After that wire the alternator to your system properly.

As long as you get the proper case alternator you might be able to buy a bigger one than Ford provides. Of course you would have to make sure the pulley size is correct. I'd hate to build out an alternator then not get a belt to fit properly.
 

·
Administrator
Joined
·
33,294 Posts
with my ACR and a single alt truck ( with a larger 180 amp alt ) on a non PCM alternator truck, I have not seen the ACR drop the aux batteries at any point after the truck batteries are over the ACR threshold
I have dual 6 volts ( camper) and dual 12 volt AGM ( bed) all combined while charging
my ACR is a dual direction and can be forced to combine at time with a switch

for you I agree the standalone alt is what I would like for this but is complex and $$ ,, as far as float i run solar also so when disconnected
the camper charges ( i can hear the dual direction ACR click on and off also and then the truck is charging from the solar when the camper batteries are over the threshold so another win

I really do not think we have anyone here that will be able to tell you definitively if your programming is possible let alone provide you with details
I would see what the Earth roamers are doing
 

·
Premium Member
Joined
·
7,616 Posts
Something seriously wrong with this scenario, 4 batteries should run 2 pc's like a week
running the power up from 12 volts -- than back down to 12 volts (also 5 and 3.3) is not efficient
at the most each PC is using about 150 watts on the 12 volt rail

the little gell cell battery(7Ah) in the backup power supply will run a PC and monitor for 30 minutes easy

why not just run the generator on the RV for the high amp loads?
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #11 ·
Something seriously wrong with this scenario, 4 batteries should run 2 pc's like a week
running the power up from 12 volts -- than back down to 12 volts (also 5 and 3.3) is not efficient
at the most each PC is using about 150 watts on the 12 volt rail

the little gell cell battery(7Ah) in the backup power supply will run a PC and monitor for 30 minutes easy

why not just run the generator on the RV for the high amp loads?
I don't have a generator in the trailer. I am able to pull into a truck stop and walk back to the trailer in the rain and work. When the batteries get low I start the truck with the remote.
770743
Two desktop PCs with 21" monitors, UPS, etc., draw over 800 watts. With this I am just as productive as in the office. However, this is why the charge on the batteries is important
 

·
Registered
Joined
·
618 Posts
I'm aware of a guy that was trying to rig his Silverado HD to charge and run a bank of batteries for his camper set up. I never got much into it with what he was trying, all I know is he changed his mind and claimed he saved some money by getting a little Honda Gen for the bank, installed it in his bed of his truck, added a lockable topper over his bed of the truck and added a Sam's wholesale security video to his camper, that way he could watch a monitor over the bed of his truck as well.

This pass summer he said he had plans to mount the Little Honda in his camper and pipe out the exhaust. He talked about adding air flow in the box, and using some motorcycle electric start idea on it, he was gonna make a support in one of the storage holdings under him and use his floor as a quick opening to have access to the Gen to turn on when needed or refuel that way he never had to go out in the rain or cold of his truck on operating the Gen. Eh, he loves this crap.

I personally told him look into solar, this stuff has changed and can provide some serious power in smaller packages, and is safer, it won't accidentally put you to sleep lol.
 

·
Premium Member
Joined
·
7,616 Posts
Part of the problem with the short run time is too large of inverter -- there is quite a bit of unused power wasted in an inverter that is too large for the job
the little inverter I use in my service truck will run the laptop all day -- tho usually the truck only sits for no more than 4 hours
the large monitors only pull about 30 watts each

so, a smaller inverter for the computers, or better yet no inverter and use the 12 volt straight with a regulated power supply
and a larger inverter for the coffee maker -- that is turned off as soon as the brew is done
then another small inverter for the lights -- or 12 volt
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #15 ·
Part of the problem with the short run time is too large of inverter -- there is quite a bit of unused power wasted in an inverter that is too large for the job
the little inverter I use in my service truck will run the laptop all day -- tho usually the truck only sits for no more than 4 hours
the large monitors only pull about 30 watts each

so, a smaller inverter for the computers, or better yet no inverter and use the 12 volt straight with a regulated power supply
and a larger inverter for the coffee maker -- that is turned off as soon as the brew is done
then another small inverter for the lights -- or 12 volt
I run the entire trailer off this. Microwave, coffee pot, fans, etc. I need the larger inverter. I would like to run the A/C even if it was for a short period so the inverter is not too large. My need is bigger then just the PCs.
 

·
Premium Member
Joined
·
7,616 Posts
then your approach is entirely wrong, get a small generator or put up with short battery run times -- that would be less expensive in the long run and more resource efficient
 

·
Administrator
Joined
·
33,294 Posts
AC on an inverter
welcome to huge LiPo battery bank and way mote than a truck alternator for recharging
 

·
Registered
2012 F-350 6.7, 2019 Corvette c7, 2011 Infiniti G-37 Convertible, 2019 Nissan Leaf, 1974 Mazda REPU
Joined
·
80 Posts
I'm seconding the generator idea in the truck bed. I have a 3200Kw electric start generator to run my 40' living quarters setup. Easily starts/runs the A/C, lights, TV, sat dish and laptop plus a small 12v fridge. You can run for 8 hours on a tank of gas or go propane and run 12-14 hours on a small propane tank. Mounted in the bed of your tuck you won't hear it.

 
1 - 18 of 18 Posts
Top