I didn't connect the red switch (as it's not necessary to operate the relay). My understanding is that the relay switch will stay depressed until both batteries are equally charged.
Blue Sea ML-ACR 500 AMP Dual Battery with remote wiring and modification to isolate when car off
- Thread starter LSDbrand
- Start date
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Appreciate the quick response Dr. Gil -
Yeah, I though about doing without the switch too.
As long as the manual switch is turned to "Remote" position without the lock depressed then it will automatically connect and isolate correct?
Then if you need a jump start you can just depress the mag lock...
Pretty sure that is my understanding.
Yes, I believe that's how mine works. It's been very headache free for years.
Works for me. Thats the kind of confirmation i needed. Thanks again and hope you're staying healthy.
Dave 2000
Not all Land Rovers are useless!
That is normal operation. Depending on a number of factors the batteries will stay connected together, this will depend on the condition of the batteries, the amount of parasitic draw on the batteries, the distance the vehicle was driven before parking up and so forth.
In the summer with just the alarm set the batteries remain connected together for around three days, in the winter this would drop to two days. After a couple of years as battery performance starts to fall they will disengage earlier, so if you use the vehicle daily you may not see the batteries become isolated. As a quick test and the ACR button in 'AUTO' and with the engine off but ignition on, switch on your headlights, after a short while you will hear a clunk as the ACR disengages. If all is well once the relay disengages turn lights and ignition off and lock the car, if the batteries are in good condition you often hear the relay clunk a short while later and join the batteries again. If not after about 30 minutes go out and start the engine, after a few seconds the relay should engage.
Regards
Dave
X2. Couldn’t have explained it better. This is my guess at why it’s staying combined also.
I have a question (maybe some questions) about hooking up my ML-ACR.
I have a solar electrical system in my camper van, and I am trying to add the ACR so that I have an extra way to charge my house battery bank if I'm not getting enough sun, or maybe if I need a bit more power at night, or whatever, I can just turn on the engine.
I was going to hook up the brown wire of the ACR to the starter to "isolate Start circuits from the House circuit and prevent starting current transients from interfering with sensitive house electronics"
After reading this thread, I'm worried that if I keep the remote switch set to AUTO (which I was hoping I would be able to do because I want to set it and forget it), the starter battery and house battery will stay combined overnight when my engine is off. That doesn't make sense to me. All I want it to do is charge my house battery when my engine is running. Any help would be appreciated.
I have a solar electrical system in my camper van, and I am trying to add the ACR so that I have an extra way to charge my house battery bank if I'm not getting enough sun, or maybe if I need a bit more power at night, or whatever, I can just turn on the engine.
I was going to hook up the brown wire of the ACR to the starter to "isolate Start circuits from the House circuit and prevent starting current transients from interfering with sensitive house electronics"
After reading this thread, I'm worried that if I keep the remote switch set to AUTO (which I was hoping I would be able to do because I want to set it and forget it), the starter battery and house battery will stay combined overnight when my engine is off. That doesn't make sense to me. All I want it to do is charge my house battery when my engine is running. Any help would be appreciated.
- Thread starter
- #28
hey bro
so basically they will stay connected but will automatically disconnect when the voltage goes under 12.65 volt, then they will be premaritally disconnected until the voltage goes over 12.65 for a couple of minutes. EX. if the night goes and the voltage is 13.5 volts, the batteries will be combined.
then at 4am the voltage has dropped to 12.64V from use, so the system automatically disconnects the batteries. At this point, battery A and B are separeted.
then 8am comes along, the solar panel start to make some voltage and one of the bateries starts to gain voltage. 12.4.....12.5.....12.6......12.7......12.8.... when this voltage stays over 12.65 for a couple of minutes the system combines again and then you have A and B combined.
My reasoning around my modification is (and it has worked very well on an overlanding trip for 1 year over central America), that the battery A and B are not at the same age and use. So they hold different charges.
if i fully charge battery A it holds a 13V charge
if i fully charge battery B it hold a 12.7V charge, its an older battery.
So i wanted to isolate them imediately after i turned off the car so that one stayed at 13 and the other at 12.7 and not battery B steal charge from A until they are both at 12.7, hens loosing 0.3V from one battery.
I hope this answers your question.
Also, as a note the BROWN wire and any isolation wire works a a trigger, so it wont STAY isolated even if you continue to send voltage to the BROWN wire. it will isolate, then it will check if the voltage is over 12.64 for a couple of minutes and if true it will combine them again, even if the BROWN wire still has voltage on it.
cheers
Yes, it makes sense why you wanted to do that. I'm wondering if I should do something like that because I don't see the point in having the batteries combined when the engine is off. What would be the purpose of that?
My vehicle is 2019 and the house batteries I just bought in 2019 as well, so they should all be equal quality/age/voltage I would think (obviously I can check, but I haven't, and it's currently raining). So should not worry about them being combined when the engine is off? Or would I need to switch the ACR to OFF when the engine is not running, or at night, etc...?
I just wanted something that would charge my house battery when my engine is running without me having to think to remember to do anything, like turn on or off switches, etc. I didn't want to have to turn things on/off, worry about batteries draining, etc.
- Thread starter
- #30
Well, to be honest there are other systems that are a lot cheaper that do that, combine when on, disconnect when off.
this one in particular is more if you need the following.
1. you want to be able to have 500Amps current between the batteries, Ex. a winch application where you need more amp hours or some other heavy equipment.
2. you want to have both batteries supporting your load when the car is off. Ex. you have a big fridge also you have some lights, a fan, stereo, etc. So a single battery would discharge if all was drained from only one, this way, you can use both batteries while the voltage is high (over 12.64) and if it starts to go lower it disconnects, keeps one battery at 12.64 and then starts to use the other one. even if you kill it, you alwyas have a start up battery.
for your application it sound like a simple ON/OFF switch that does not interpret the voltage of the batteries would be sufficient.
On the topic of your batteries, they have to be EXACTLY the same for them to hold the same voltage and stuff, not only the same model but also the same age. Since I was going on such a long trip i knew that at one point my aux battery was going to get so much use it would behave like an older battery and drain my "newer" or less used one. so i opted for this solution and it worked extremely well. I also made sure that all my load could sufficed by only my AUX battery.
let me know if you have any questions or write me a DM about your system and ill give you my input
- Thread starter
- #31
also, just to finish up, i would put a fuse or a bulb where i recomend on the description, i put a fuse on my car and i did blow it about 3-4 times because i would combine the batteries with the switch to ON and forget and turn off the car shorting the wire and making the fuse blow. I ended up putting a light and it was a reminder i did since the light would turn of iff i did this.
I had very specific reasons to turn the switch to ON manually while the car was on.
cheers
Dave 2000
Not all Land Rovers are useless!
As long as your VCR is 'dual sense' then there are no issues as to your charge source connections to either bttery. As you said it it is better to 'fit and forget', the exact way I have used mine for many years.
I have one battery direct to the starter, the other battery (aux) to the various other circuits on the car. I use the solar charger connected to the aux. Assume neither panel is plugged in and the car is left untouched for a couple of days the parasitic draw is applied to both batteries but it really is a very small amount.
If either of the panels are plugged in and it is fairly bright out (not necessarily sunny) after a short while the aux battery has reached the voltage that allows the VCR to 'combine' assuming the override switch is in the 'auto' position.
If the engine is started the same rules apply, there are some mods what to some may seem odd with my installation but they include a relay that disables the solar charger when the engine in started.
regards
Dave
I have one battery direct to the starter, the other battery (aux) to the various other circuits on the car. I use the solar charger connected to the aux. Assume neither panel is plugged in and the car is left untouched for a couple of days the parasitic draw is applied to both batteries but it really is a very small amount.
If either of the panels are plugged in and it is fairly bright out (not necessarily sunny) after a short while the aux battery has reached the voltage that allows the VCR to 'combine' assuming the override switch is in the 'auto' position.
If the engine is started the same rules apply, there are some mods what to some may seem odd with my installation but they include a relay that disables the solar charger when the engine in started.
regards
Dave
Yeah I think mine will be just fine installing the ML-ACR as usual with the starter isolation. I think the batteries being combined when engine is off should be fine with my set up.
Well, here is the start of my system. After chatting with a few shops and vendors @LC4LIFE aka HuddExpo was able to solve my concerns with a modified big kit. Most cruiser shops have great solutions, however I thought HuddExpo had the most thought out solution, that met my needs. His wiring is also a work of art.
I then got with @NLXTACY aka Wits' End who was kind enough to share some files for a blue sea mount. Man I love that guy, Thanks Joey!
My good friend works for a local union, he was able to order me some custom mounts per King Joey's Specs. However due to covid I just got them today. Apparently they are longer than joeys specs so that we could cut them down.
So far I have two mounting options for a blue sea system.
Option 1 with a Blue Sea fuse panel and breaker mounted, with the Blue Sea solenoid on the cruiser control as per HuddExpo specs.
Option 2 the solenoid mounted with the panel and with the fuse panel, and a breaker mounter near by.
Either way I will be running power to the back for another Blue Sea panel on my Wit's End QPM for a ARB pump, fridge, and lighting.
I already have an OEM dual battery tray set up and a Slee bottle relocation kit.
Hopefully in the coming weeks I can get some measurements to @LC4LIFE and get the mounts to powder coat once they are drilled and trimmed to spec.
Any feed back would be great! Happy Cruising!
I then got with @NLXTACY aka Wits' End who was kind enough to share some files for a blue sea mount. Man I love that guy, Thanks Joey!
My good friend works for a local union, he was able to order me some custom mounts per King Joey's Specs. However due to covid I just got them today. Apparently they are longer than joeys specs so that we could cut them down.
So far I have two mounting options for a blue sea system.
Option 1 with a Blue Sea fuse panel and breaker mounted, with the Blue Sea solenoid on the cruiser control as per HuddExpo specs.
Option 2 the solenoid mounted with the panel and with the fuse panel, and a breaker mounter near by.
Either way I will be running power to the back for another Blue Sea panel on my Wit's End QPM for a ARB pump, fridge, and lighting.
I already have an OEM dual battery tray set up and a Slee bottle relocation kit.
Hopefully in the coming weeks I can get some measurements to @LC4LIFE and get the mounts to powder coat once they are drilled and trimmed to spec.
Any feed back would be great! Happy Cruising!
OK, I have another question about hooking up my ML-ACR.
I have the 500 amp one from blue sea. So does that mean I need 4/0 cable? Or can I use 2/0 cable?
Also, does the fuse between the ACR and starter battery need to be 500 amps or greater?
My ram promaster's alternator is either 180 or 220... So would it ever even get to 500 amps?
I was originally going to just use 2/0 wire with a 250amp fuse because my alternator is definitely less than that...
I read that the amperage of the ACR is just to support an alternator of that size, so I need to size wiring and fuses based on my alternator, not the ACR, right?
Thanks!
I have the 500 amp one from blue sea. So does that mean I need 4/0 cable? Or can I use 2/0 cable?
Also, does the fuse between the ACR and starter battery need to be 500 amps or greater?
My ram promaster's alternator is either 180 or 220... So would it ever even get to 500 amps?
I was originally going to just use 2/0 wire with a 250amp fuse because my alternator is definitely less than that...
I read that the amperage of the ACR is just to support an alternator of that size, so I need to size wiring and fuses based on my alternator, not the ACR, right?
Thanks!
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Thanks, I have the instructions. It was confusing though because it says for 500 amps to use 2x 4/0 wire. Since I have the 500 amp ML-ACR, I was confused. However, I believe I need to only use wire based on my vehicle's alternator max amperage (which is definitely not over 220). The ML-ACR can handle 500 amps. That's all that means.
I am going to go with 2/0 cable because my alternator does not put out enough power to warrant 4/0.
