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CAJW's avatar
CAJW
Explorer
Mar 04, 2016

ACR install on 2013 Chevy

This writeup is in response to a request to detail the specifics of this install. I had not been successful in finding a writeup on a 2013 Chevy install to fix the battery drain issue, so I read/researched the subject until I was crosseyed. I'm not going to get into discussions about methodology, wire size, equipment choice etc, as there are many opinions as to the best way to accomplish this. I'm detailing what I did after lots of research and discussions with industry techs, who recommended this equipment and agreed with my conclusions.

Due to Chevy's stock wiring that keeps the trailer aux wire hot all the time, with some bad luck and/or excessive house battery drain, one could find themselves with a vehicle battery dead as well. There are a number of ways to fix this from solenoids, diodes, manual switches, etc., but I decided to go the ACR (automatic charging relay) route. As the name implies, battery connect/disconnect is automatic, with no input from the operator needed, hence nothing to remember (or in my case, forget).

I used the Blue Sea #7611 ACR, as per my conversation with the Blue Sea Tech Rep (very helpful, who provided excellent customer service) along with one of their 50A circuit breakers, model # 7183. I also used a dedicated 10ga. wire in a 1/2" loom run from the ACR down the firewall, then alongside the factory loom attached to the driverside frame rail to the 7way connector located in the forward driverside pickup bed panel. The toughest part of this install was locating the ACR to allow removal of the factory fuse box cover, ACR cover access and battery terminal or battery removal, without having to remove other appliances. I did have to replace the bolt used for the fender brace with a shorter one that cleared the ACR cover with a buttonhead allen screw and nyloc nut.

I found a spot to mount the ACR on the driverside fender, behind the battery, ahead of the fuse box, tucked up almost to the top of the panel. This location allows access to all items mentioned earlier, but is very close quarters to the fuse box. If someone does this install, I suggest to get your wiring and terminals mocked up to confirm everything will fit with access to terminals and allows covers to be removed, before drilling your mounting holes.
The circuit breaker was mounted just below the ACR and the inline fuse for the ACR is in between the two appliances.

The system works as advertised and its nice knowing my vehicle batteries are now isolated from the house batteries anytime the truck engine is shutdown. Hopefully this will be of benefit to someone that is searching for a fix to this issue.



  • If you are worried about exceeding the 130 amp rating, or starting the truck from the camper, you will need a lot larger the #10 wire and a lift gate plug between the camper and truck.

    Another thing to be aware of with charge sensing combiner relays is that it may not disconnect (once connected) if there is a charge source on the far side. If you have solar on the camper, run the truck (which connects the relay) then shut it down, if the system voltage continues to be held up by the solar, the relay will stay closed. Often that is a good thing, but sometimes a surprise.
  • RoyB's avatar
    RoyB
    Explorer II
    Grit Dog - You bet.... I am aware of the problems and fixes. My additional battery install is primarily to support my two way Radios Operations from the stand alone truck as well as adding additional batteries to the OFF-ROAD Trailer setup when camping back off the grid. On my diagram above you can see where I plug a second 2-conductor cable into the truck bed battery bank when in camping mode with the off-road trailer. An additional feature is going to SI-ACR manual mode I can switch in the truck bed batteries to help start my truck if the truck start battery has discharged some...

    I love PLAN Bs...

    My 2010 F150 truck has all kinds of system items running when I turn the key off... Once the truck start battery gets down abit it goes pretty fast just sitting in the driveway for a couple of weeks not being used... My older 2004 F150 wasn't quite as bad doing this compared to the newer F150... If I drive my truck alot I don't have this problem so this is telling me I am not getting a fully charged truck start with my short runs every three or four days. The problem of being retired haha...

    I used to solve the problem with a small solar panel sitting on the dash... Probably should dig that out again and use it more...

    I won't be disconnecting the truck start battery to keep it from discharging. That will cost you $90 at the Ford place for 5 minutes work effort to reset all of the computer settings that the books says will re-learn when the truck start battery has been disconnected. Been there done that already...

    Another golden rule I have is to never mess with the truck start system when camping off the power grid. This is you only way to get back home haha...

    Thanks for the reality checks...

    Roy Ken
  • RoyB wrote:
    X2 on the Blue Sea SI-ACR Automatic Charging Relay setup. It certainly appears to parallel the auxiliary batteries during charging, and isolates them when charging has stopped and after auxiliary battery voltage has fallen.

    It does not appear however in my case to keep the parasitic Truck system loads from running down the Truck start battery. If I let my Ford truck sit for a couple of weeks the truck start battery starts loosing it charge. I suspect using the manual over-ride of the SI-ACR setup would rejuvenate my truck start battery allowing me to start the engine...

    This would be a great feature to have for me to supplement my Ham radio operations from my truck setup...

    This is my proposed setup using the Blue Sea SI ACR setup... My only untested fear is going to be will this extra load of the auxiliary batteries overload my standard OEM Truck Alternator system.


    Love your TC setup and towing the Jeep.

    Roy Ken

    This is not a fix for a problem with your truck's electrical system, presuming you're talking about just the truck and not sitting hooked to your camper long term.
    You should not have to have a battery disconnect on your truck to protect itself from its own problem, as the truck battery should last much longer than a couple weeks without being run/charged. That's a separate problem and I would not want to cut into the charging circuit and mod it and the battery output to fix the problem, although it would fix it, idk what else you may affect by doing it.
  • WyoTraveler wrote:
    Will work well and I'm sure you'll be happy with it. You could have done same thing for about $6. So I think it is great for you, not sure it would be that much of an exciting product for other RVers that could do same thing for $6. JMHO

    Do tell how you create a $6 automatic charging circuit/disconnect.
  • Will work well and I'm sure you'll be happy with it. You could have done same thing for about $6. So I think it is great for you, not sure it would be that much of an exciting product for other RVers that could do same thing for $6. JMHO
  • Nice clean install.

    I am looking at doing the same install - almost. You used the 7610 ACR. I was looking at their Add-A-Battery kit #7650 that includes a battery disconnect. This kit uses the 7611 ACR. Both 7610 and 7611 are rated at 120A continuous duty.

    I called Blue Sea because my alternator puts out 130 amps and I may go to a larger alternator. I asked the rep if the ACR would just ignore the extra 10 amps or what? He said not to use it and recommended the 7620 or 7622 that are rated for 500A continuous.

    So check your alternator output and choose an ACR accordingly.

    Bill
  • RoyB's avatar
    RoyB
    Explorer II
    X2 on the Blue Sea SI-ACR Automatic Charging Relay setup. It certainly appears to parallel the auxiliary batteries during charging, and isolates them when charging has stopped and after auxiliary battery voltage has fallen.

    It does not appear however in my case to keep the parasitic Truck system loads from running down the Truck start battery. If I let my Ford truck sit for a couple of weeks the truck start battery starts loosing it charge. I suspect using the manual over-ride of the SI-ACR setup would rejuvenate my truck start battery allowing me to start the engine...

    This would be a great feature to have for me to supplement my Ham radio operations from my truck setup...

    This is my proposed setup using the Blue Sea SI ACR setup... My only untested fear is going to be will this extra load of the auxiliary batteries overload my standard OEM Truck Alternator system.


    Love your TC setup and towing the Jeep.

    Roy Ken