I'm about to install dual batteries in my 1997 80 series and I was wondering if someone could look over my wiring diagrams for errors. Other than wiring a car stereo, I haven't done a lot of electrical work. Thanks!
Wiring Diagram - How badly did I screw this up? (1 Viewer)
- Thread starter Aeneiad
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well, I can't tell what all those electronics bits are but presumably one of those batteries has the negative terminal to ground as well? Otherwise there may be an issue. 
Are you relying on the body for future accessories to get to ground?
Are you relying on the body for future accessories to get to ground?
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- Thread starter
- #3
Yeah, I definitely forgot to add that. The start battery, (on the right) has the factory ground.
There are 3 16GA wires on the ACR. Ground & Start Isolation need to be hooked up.
Fuse all your positive leads as close to the battery as possible. I’d go with AMG or ANL 150a fuse for each lead going from battery to ACR. Circuit breaker for the fuse block in the quarter panel would also need to be close to the battery, or fuse that aux positive at the battery then in addition add the CB at the fuse block for easy cutting of power.
Grounds are important. I grounded my aux batt to match the start battery. One 8awg body ground at the PS inner fender, one 2awg ground to the block under the exhaust manifold. i Tend to ground accessories at the battery when possible or run a large cable to a common negative block and ground accessories there.
Grounds are important. I grounded my aux batt to match the start battery. One 8awg body ground at the PS inner fender, one 2awg ground to the block under the exhaust manifold. i Tend to ground accessories at the battery when possible or run a large cable to a common negative block and ground accessories there.
I utilized similar components. But didn’t go the dual battery route. I ran 4ga marine from the starting battery all the way to the rear fuse block. Someday I may go dual battery, but for the time being, it works good.
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I believe only the reference "black" wire or ground needs to be hooked up for it to function.
I'm about to install dual batteries in my 1997 80 series and I was wondering if someone could look over my wiring diagrams for errors. Other than wiring a car stereo, I haven't done a lot of electrical work. Thanks!
Unless the batteries are next to each other, I assume they are on separate sides of the engine bay. You need to add a fuses.
That’s what I thought. Batteries never auto-combined until red wire was hooked up to a switched positive.
For ML-ACR series the red wire is the override. The ACR will work with just the black wire hooked up. It might be mis-wired or malfunctioning if it wasn’t working for you with just the black wire. Make sure that your reference ground was not isolated from the “engine” ground.
Delta VS
Supporting Vendor
The only thing that could be optimized there is the ground, and only for the purpose of using less wire. The start battery grounds to the engine block, and as @Shoredreamer says, there is a nice spot to do the same for the second battery.
Had just put together a similar diagram for our components: Basic Dual Battery Diagram
Had just put together a similar diagram for our components: Basic Dual Battery Diagram
Negative to negative on the battery? Where is the ground wire?
Ground is via the main battery grounds.
I've mine wired like that for years - should be functionally identical vs a ground to the block on the Aux battery right ?
Asking to ensure I'm not driving a fireball in waiting
I've mine wired like that for years - should be functionally identical vs a ground to the block on the Aux battery right ?
Asking to ensure I'm not driving a fireball in waiting
Yo guys - Thread hi-jack here (since it is an old thread I figure it doesn't matter and still sorta on topic).
First let me say this is going in an old ambulance that has all manner of wiring fookery but I am more interested in the Blue Sea ML-ACR function.
So I apologize if this is sort of "out there" but the questions and wiring about the ACR are more the topic and not the ambo part.
For background, here is the nightmare under the front seat of the ambo:
Here is everything labeled and a description from someone smarter than me:
"
B+h (house battery positive) - I had already disconnected this before snapping the photo, but it was connected to the post where the arrow is drawn. This went to the "hot spare" battery bank (the rear two in the side box). We rewired the side battery box so that all 3 are in parallel.
B+s1 (starting battery positive 1) - This connected to the under-hood battery. With our conversion, we replaced the upfront battery with the biggest one we could fit, and this became the *only* starting battery.
B+s2 (starting battery positive 2) - This connected to the front-most battery in the side box, and was in parallel with the under-hood starting battery. Since we wanted 3 batteries in our house bank, we removed this wire entirely.
A - This solenoid is controlled by the module on/off switch above the driver.
B - This is the manual module disconnect switch. [Note: Not all Leaders have this. My 2000 does not.]
We didn't want to power a solenoid just to have the ability to use the house system, so we put these switches in parallel instead of series... and we never really use the solenoid.
C - This is a timer that allows the lights/etc to run for a configurable amount of time after the keys are pulled. Ours malfunctioned and we didn't want it anyhow. I'd highly recommend sending it to the trash.
D - This is actually a battery isolator (2 diodes) but it's being used instead as a huge single diode (notice the bridge). This takes power from the center post (which is connected to the starter battery and alternators), and sends it to the "hot spare" (aka house) batteries without letting electricity flow back the other way.
This kind of setup is only relevant with a "spare" battery bank, and is useless if you want 2 independently functioning systems. You'll want to remove all of this.
E - This solenoid is for "emergency start" and connects the "hot spare" system to the starting system. We kept this, and have used it on several occasions (really cold starts)!"
For fun, here is a pic of the massive isolator/diode:
Here is a schematic of what I am trying to achieve (it is not unlike what @Aeneiad was doing) The ambo has two alternators BTW:
This is what the accessory or "house" system looks like and could be in any expo rig:
The specific question I have is more about clarification of the function of the ACR. I am installing a 7620. Does the ACR take the place of an isolator and also work for emergency starting? It reads as though it does.
Less important to Mud, these are the actual questions I have as it pertains to the ambo wiring. I know we have some gurus in here that might know the answers:
1) Do I still need to run "D" (The diode/Isolator) with the ACR? I know the ACR allows charging of all the batteries, combining of all the batteries and will automatically disconnect the batteries should one side become low (below9.6v) or overcharged (above 16.2v). It reads like it does all the same things as both D and E.
2) With above, can I delete "E" (emergency start solenoid and switch) and then the ACR can take its place (switching to "on" to combine the batteries) in the event of a discharged or cold start issue?
So if the ACR 7620 does the stuff it says ( and I am not imagining that I actually understand it), it would seem I can delete the diode/isolator and emergency start solenoid and just run the ACR right?
Looking at @Delta VS diagram he linked above I think I am understanding this just fine but am hoping for some reassurance since I will be ripping some stuff out.
First let me say this is going in an old ambulance that has all manner of wiring fookery but I am more interested in the Blue Sea ML-ACR function.
So I apologize if this is sort of "out there" but the questions and wiring about the ACR are more the topic and not the ambo part.
For background, here is the nightmare under the front seat of the ambo:
Here is everything labeled and a description from someone smarter than me:
"
B+h (house battery positive) - I had already disconnected this before snapping the photo, but it was connected to the post where the arrow is drawn. This went to the "hot spare" battery bank (the rear two in the side box). We rewired the side battery box so that all 3 are in parallel.
B+s1 (starting battery positive 1) - This connected to the under-hood battery. With our conversion, we replaced the upfront battery with the biggest one we could fit, and this became the *only* starting battery.
B+s2 (starting battery positive 2) - This connected to the front-most battery in the side box, and was in parallel with the under-hood starting battery. Since we wanted 3 batteries in our house bank, we removed this wire entirely.
A - This solenoid is controlled by the module on/off switch above the driver.
B - This is the manual module disconnect switch. [Note: Not all Leaders have this. My 2000 does not.]
We didn't want to power a solenoid just to have the ability to use the house system, so we put these switches in parallel instead of series... and we never really use the solenoid.
C - This is a timer that allows the lights/etc to run for a configurable amount of time after the keys are pulled. Ours malfunctioned and we didn't want it anyhow. I'd highly recommend sending it to the trash.
D - This is actually a battery isolator (2 diodes) but it's being used instead as a huge single diode (notice the bridge). This takes power from the center post (which is connected to the starter battery and alternators), and sends it to the "hot spare" (aka house) batteries without letting electricity flow back the other way.
This kind of setup is only relevant with a "spare" battery bank, and is useless if you want 2 independently functioning systems. You'll want to remove all of this.
E - This solenoid is for "emergency start" and connects the "hot spare" system to the starting system. We kept this, and have used it on several occasions (really cold starts)!"
For fun, here is a pic of the massive isolator/diode:
Here is a schematic of what I am trying to achieve (it is not unlike what @Aeneiad was doing) The ambo has two alternators BTW:
This is what the accessory or "house" system looks like and could be in any expo rig:
The specific question I have is more about clarification of the function of the ACR. I am installing a 7620. Does the ACR take the place of an isolator and also work for emergency starting? It reads as though it does.
Less important to Mud, these are the actual questions I have as it pertains to the ambo wiring. I know we have some gurus in here that might know the answers:
1) Do I still need to run "D" (The diode/Isolator) with the ACR? I know the ACR allows charging of all the batteries, combining of all the batteries and will automatically disconnect the batteries should one side become low (below9.6v) or overcharged (above 16.2v). It reads like it does all the same things as both D and E.
2) With above, can I delete "E" (emergency start solenoid and switch) and then the ACR can take its place (switching to "on" to combine the batteries) in the event of a discharged or cold start issue?
So if the ACR 7620 does the stuff it says ( and I am not imagining that I actually understand it), it would seem I can delete the diode/isolator and emergency start solenoid and just run the ACR right?
Looking at @Delta VS diagram he linked above I think I am understanding this just fine but am hoping for some reassurance since I will be ripping some stuff out.
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Delta VS
Supporting Vendor
You can download a much nicer/more detailed version of this at the bottom of the page here: Delta Vehicle Systems - DeltaVS 80 Series PROharness Wiring Kits - https://www.deltavs.com/all-products/deltavs-80-series-wiring-proharness
Thanks.
Any insight on the questions?
Delta VS
Supporting Vendor
7623 is more recommended as it allows manual control to do what you want
Yes, 7623 is better as you can manually link the terminals if you need to.
Yes the ACR will link the batteries over charging voltage and disconnect them under charging threshold. (That’s all that it does). You don’t need to have a separate isolator.
On batteries, if you want to select between different banks, you will need another relay as ACR is only one part of the system. However, since id imagine you only two battery systems, an ACR is sufficient.
If you wanted to for example, start your car from another battery (house battery), without linking the house and starting battery together, then you would need to have a battery selector.
If your starting battery dies right now, you would link the ACR, which would combine the the two systems, and start it that way.
In the E350 - which is the tow rig - the big diesel has two starting batteries (per the diagram) and I will be running just two "house batteries." So yeah, just the two systems.
I was able to get a 7620 for cheap so will likely stick with it. Plus it will live under the driver's seat where it is hard to get to. I guess if I wanted to lock out for service now I can just turn the Blue Sea switch to off and physically disconnect the house batteries.
Or I could add one of their 6007 switches on the side of the seat.
I just found this video which gives a really good description of the two versions as well as the addition of the switch.
I appreciate the responses. I thought I understood what was happening but i did not want to rip out the stuff under the seat and then realize I still needed a part of it!
You will want to install some fuses, especially if you have runs from the engine bay to the cabin. See how many amps you will draw (load you have), side your wire to those amps based on the length, and size an insta trip over current fuse under that number. You can get resettable busman fuses on amazon
