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Enabling dual battery mode

Posted: Sat Aug 19, 2017 1:14 pm
by apsilon
Interested in trying dual battery mode as I believe this basically turns off smart charge. Is it just a matter of enabling it in the BdyCM? Just want to make sure something else doesn't need to be changed.

Bit of background as to why I want to try it. I run a dashcam that has a parking mode. Basically while parked it continues recording at 1fps. I have it set to turn off completely if the battery voltage drops to 12.2v

At first I was able to get 8 hours of recording in this mode but now, a few months later, I only get around 4 hours. I'm wondering if the battery isn't really getting a full charge due to the smart charge feature. It shows 12.5v when I stop the car, it's just the voltage drops much faster than it did when the battery was brand new.

Re: Enabling dual battery mode

Posted: Sat Aug 19, 2017 6:46 pm
by saeb
Try it and if it makes no difference just revert it back.

You can change it in the non asbuilt BCM section as it's already in there.

Re: Enabling dual battery mode

Posted: Sun Aug 20, 2017 7:55 am
by apsilon
saeb wrote: Sat Aug 19, 2017 6:46 pm You can change it in the non asbuilt BCM section as it's already in there.
Yeah, that's what I meant. The part where you just have a choice of either single or dual battery. Just wasn't sure if that was all that was required.

Re: Enabling dual battery mode

Posted: Sun Aug 20, 2017 8:09 am
by saeb
apsilon wrote: Sun Aug 20, 2017 7:55 am
saeb wrote: Sat Aug 19, 2017 6:46 pm You can change it in the non asbuilt BCM section as it's already in there.
Yeah, that's what I meant. The part where you just have a choice of either single or dual battery. Just wasn't sure if that was all that was required.
No, that is all. If you can watch your battery voltage at first that will be a bonus, just to confirm your voltage is not dropping back to 12v when driving.

Re: Enabling dual battery mode

Posted: Sun Aug 20, 2017 11:03 am
by apsilon
Made the change and took it for a drive. Charge seems to sit between 14.2 and 14.5v constant. I'll see how it goes in terms of impacting recording time I get through the week.

Re: Enabling dual battery mode

Posted: Fri Aug 25, 2017 6:54 pm
by apsilon
So, my week has been more interrupted than usual so today was the only day where the car was parked from the time I arrived at work until the time I left and I got 8 hours of recording again. Once could be a fluke so I won't say for certain that it's due to smart charge no longer being active but I think it's a good sign.

Re: Enabling dual battery mode

Posted: Fri Aug 25, 2017 7:09 pm
by saeb
I would assume that the BMS never pushes the battery to full charge for a reason. Most of the time when I was monitoring it before I ran out of mgauge positions I would only see on average a 6 ah going into the battery. So I can understand on short trips each day why you would not see a higher charge.

Think back a remember a well publicised Ford Everest under bonnet fire. It was said the battery was not secured down properly, I'm thinking this may have been a bum steer and that the battery split from over charging and was the cause of the fire.

Ford are pushing there dealers pretty hard to not enable dual battery mode unless dual batteries are actually installed. You have to ask yourself why? Put 2 and 2 together and the mind wonders......

Re: Enabling dual battery mode

Posted: Fri Aug 25, 2017 7:35 pm
by apsilon
Worth considering but you would hope that would not be an issue. Afterall smart charge is only a recent thing, for decades car batteries have been able to be fully charged without issue. It can't be good for battery life to only ever be partially charging it either.

I'll play around a bit more yet though. Might start monitoring state of charge with dual battery disabled and get a better idea of what's happening.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 3:00 pm
by saeb
Some further information on this.

What the BMS has is a "Target State of Charge"

When dual battery mode is disabled the target is set at 12 volts.
When dual battery mode is enabled the target is set at 16 volts.

I won't get into why only 12 etc etc. I'm just telling everyone how it is set.

So do we want an option is Forscan for dual battery mode enabled or disabled or do we want and adjustable figure between 00.00 and 00.00 ?

Yes I'm currently sorting the BCM info for Forscan.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 3:44 pm
by saeb
Basically the BMS is never disabled and the people that pull their plug on the shunt at the battery are going to cause more damage than good.

The better option will be to find a setting that will change the state of change percentage from say 70% to 90% and leave the State of Charge voltage as is.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 4:07 pm
by saeb
Critical SOC is 11.52 Volts

The battery voltage is constantly watched in Single and Dual battery modes and if it will adjust the climate fan speed, coolant fan if it exists and load shed with the electronic power steering where required.

So I'm thinking

Disabled 12 Volt
Partially Enabled 13 Volt
Partially Enabled 14 Volt
Partially Enabled 15 Volt
Fully Enabled 16 Volt

In Forscan?

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 5:30 pm
by janemar
^^I thought our batteries are calcium calcium type and needs 16v to fully charge instead of 14.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 6:45 pm
by saeb
janemar wrote: Sun Aug 27, 2017 5:30 pm ^^I thought our batteries are calcium calcium type and needs 16v to fully charge instead of 14.
Its based on the state of charge. Once the voltage reaches it requires voltage charging will then drop off ie. alternator drops off and you will see 12.5 odd volts. If the battery had to be at 16 volt continuously then there would be no need for the BMS in the first place.

I never said 14, I'm saying what is the minimum you will allow when the alternator is switching.

So what should happen if say you change it to 13 volt instead of 12 then you would probably see a minimum output from the alternator of 13 and a bit volts instead of 12 and a bit. Same with 14 or 15, whatever class it as a minimum you will accept from the alternator as such.

It's the best I can explain it without sounding dumber.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 6:45 pm
by saeb
Anyway, I'm going to put my above table forward then I will give it a test to see what the outcome is.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 8:12 pm
by Fred2112
I would be interested in giving it a go and looking at the results


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Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 9:25 pm
by janemar
saeb wrote: Sun Aug 27, 2017 3:00 pm Some further information on this.

What the BMS has is a "Target State of Charge"

When dual battery mode is disabled the target is set at 12 volts.
When dual battery mode is enabled the target is set at 16 volts.

I won't get into why only 12 etc etc. I'm just telling everyone how it is set.

So do we want an option is Forscan for dual battery mode enabled or disabled or do we want and adjustable figure between 00.00 and 00.00 ?

Yes I'm currently sorting the BCM info for Forscan.
Hi Stewart,

Can you elaborate this in layman's term on me. Am Im getting it right when I say,

- When Dual batt is enabled, alternator is charging and maintaining the batt fully charged all the time since 16v is pretty much equates to 100% SOC. It won't shut off charging unless it is nowhere near 16volts?

When dual batt is disabled(default,) in the most simplest terms, it waits for the battery voltage to reach 12 volts(70%ish SOC) before it commands the alternator to start charging and giving some amps.

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 9:31 pm
by saeb
janemar that appears to be about it.

Thanks for being simple. :)

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 10:01 pm
by janemar
^^thanks mate!

I agree. I like your concept so we have a choice.

Looking forward to it!

Re: Enabling dual battery mode

Posted: Sun Aug 27, 2017 11:02 pm
by GerryP
Great stuff mate, I too like the option of choosing a voltage target level. It would allow better for differing battery chemistries as well as a bit more protection for things we plug in, like dash cams and uhf's for instance as some of these won't like to be fed 16 volts. I've already moved my uhf to my auxiliary battery as it didn't like it when I enabled dual battery mode.
Good work mate
Cheers

Re: Enabling dual battery mode

Posted: Mon Aug 28, 2017 12:44 pm
by Tony310864
I am running mine in single battery mode with out any problems. I have a volt meter that seems to read between 14volts and 14.6volts.
My current situation is no second battery in the ute, 2x105ah batteries in camper trailer with a DC/DC charger.
The DC/DC charger is in dumb alternator mode as it was set when I had my 80 series cruiser, when it was working with the Ranger I did not see any need to change it.

Sometimes I feel that to many choices leads to more confusion and problems.

Tony.

Re: Enabling dual battery mode

Posted: Tue Aug 29, 2017 1:30 pm
by Lonski
Never seen mine go above 14.6v with one or two batteries connected with Dual Battery enabled.

Re: Enabling dual battery mode

Posted: Mon Sep 04, 2017 5:42 pm
by HiroboFreak
Mine has seen 14.8/14.9 at times in DB mode.



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Re: Enabling dual battery mode

Posted: Mon Sep 04, 2017 6:21 pm
by saeb
I see about 14.6 tops. The modules are always watching the voltage so I do not see it as a biggy. They are regulated and I'm sure like most devices these days will probably happily work to at least 18 volts before bad things happen. I think I used to pump 15. something though my Land Cruiser and nothing died.

I will test my changes from 12 to 16 volts over the coming weeks as I really need more than a 15 km trip to get the alternator to go sleepy. Single battery min appears to be 12 volts and dual 16 volts so I may try it at 14 and see what everything does. There will be a better way to interpret this too you but I need to gather data first and then I can make it clear what is happening.

Undecided whether I will let the self adjustment creep into this release of Forscan but at it's only a week or so away so it may wait.

Re: Enabling dual battery mode

Posted: Mon Sep 04, 2017 6:33 pm
by apsilon
Don't know if this info is of use yet but I switched back to single battery and have been monitoring SOC for a bit over a week now. I'm yet to see SOC exceed 83%. I've had it sit at 83% for half an hour but haven't had a chance to do a longer drive as yet. Not sure if 83% is a magic number or something.

I plan on giving it at least another week, hopefully with an extended drive as well before switching to dual battery again and seeing what impact that has on SOC.

Re: Enabling dual battery mode

Posted: Mon Sep 04, 2017 7:16 pm
by saeb
I just believe Ford do not want that battery running to 100%

Also I reckon it looses Sync over time. Mine was showing 35% and engine started as normal.

Re-synced BMS as new battery and 54%.

I'm going to do a full charge with my smart charger with negative terminal unhooked from vehicle then reset the BMS once fully charged and reconnected.