Scarab 165 ID dual battery install with dual battery charger.

[jb32566]

Scarab 165 MOD dual battery with chargers

First, thanks for all the great posts out there on this. I asked questions in several of them and I didn't want to hijack anyone else's thread so I started a new one. So someone else can hijack it.

I waffled a bit on supplies and finally ended up with the following:

Charger:
Minn Kota Precision Digital Chrgr MK 220 PC 2 bank x 10 amps.

Amazon.com : Minn Kota Precision Digital Chrgr MK 220 PC 2 bank x 10 amps : Boating Battery Chargers : Sports & Outdoors

Amazon.com : Minn Kota Precision Digital Chrgr MK 220 PC 2 bank x 10 amps : Boating Battery Chargers : Sports & Outdoors

www.amazon.com

I picked the Minn Kota based on MikeyL's input here:

https://jetboaters.net/threads/new-dual-bank-charger-and-agm-batteries.4689/

Switch:
Blue Sea Systems 300 Amp m-Series Battery Switches

Amazon.com : Blue Sea Systems m-Series Mini Selector Battery Switch - Red : Boating Battery Switches : Sports & Outdoors

Amazon.com : Blue Sea Systems m-Series Mini Selector Battery Switch - Red : Boating Battery Switches : Sports & Outdoors

www.amazon.com

I went with the 6007 4 position, single circuit switch. This was mainly a personal choice and I liked that I had the ability to isolate or combine and I only really needed 1 output for now. The 165 had 2 circuits that were connected to the hot side of the installed switch and I just put those on the terminal for the secondary battery. For reference, they are the bilge pump and the housekeeping power to the stereo. I wasn't sure about the 2nd initially but I am 99% sure of it now.

ACR:
Blue Sea Systems Automatic Charging Relays (ACRs) 12/24 Si ACR:

Amazon.com: Blue Sea Systems SI-ACR Automatc Charging Relay - 12/24V DC / 120A (7610): Sports & Outdoors

Buy Blue Sea Systems SI-ACR Automatc Charging Relay - 12/24V DC / 120A (7610): Accessory Power - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

I'm not using the Si feature, but just in case a need arises in the future.

Fuses between ACR and battery:
2 Stinger SCBM100 100-AMP Marine Circuit Breaker:

Amazon.com: Stinger SCBM100 100-AMP Marine Circuit Breaker: Car Electronics

Buy Stinger SCBM100 100-AMP Marine Circuit Breaker: Everything Else - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

I tried going 2 different ways here. The first was a "Rockford Fosgate Single In-Line AGU Fuse Holder for 4 AWG or 8 AWG Wire."

Amazon.com: Rockford Fosgate Single In-Line AGU Fuse Holder for 4 AWG or 8 AWG Wire: Car Electronics

Buy Rockford Fosgate Single In-Line AGU Fuse Holder for 4 AWG or 8 AWG Wire: Fuse Holders - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

I sent them back because I decided I wanted a breaker instead of a fuse.
Choice #2 was this thing: "100A Inline Audio Circuit Breaker, PowMr Solar 12V/24V DC Circuit Breaker 100 amp with Manual Reset, Inline Fuse Holder for DC Car Audio, Stereo Switch and Solar System(2 Pack)"

Amazon.com: Temank 100A Inline Audio Circuit Breaker 12V/24V DC, Solar Circuit Breaker 100 amp with Manual Reset, Inline Fuse Holder for DC Car Audio, Stereo Switch and Solar System(2 Pack): Automotive

Buy Temank 100A Inline Audio Circuit Breaker 12V/24V DC, Solar Circuit Breaker 100 amp with Manual Reset, Inline Fuse Holder for DC Car Audio, Stereo Switch and Solar System(2 Pack): Fuse Holders - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

It arrived and I just wasn't happy with the quality so it went back and got replaced with the stingers that I should've ordered initially.

Battery & Box
I got my batter from Advance Auto Parts. I may replace it later, but the battery was one of the last things I bought and this was the best choice without driving an hour.

Advance Auto Parts - Down for Maintenance

I didn't get fancy with the box either.
Attwood 9092-5 Battery Tray- 24 Series

Amazon.com : Attwood Battery Tray- 24 Series, black, 12-3/8" L x 7-1/8" W, 7" L x 11" W : Boating Navigation Lights : Sports & Outdoors

Amazon.com : Attwood Battery Tray- 24 Series, black, 12-3/8" L x 7-1/8" W, 7" L x 11" W : Boating Navigation Lights : Sports & Outdoors

www.amazon.com

Misc:
2x25' 4AWG red wire
(I think I could've gotten away with half that, but I ran the ACR and switch connections separately. more on that later.)
2x25' 4AWG black wire
(Could've gone with half of this.)
16? Pack 4 Gauge 4 AWG 3/8" Stud UL Marine Grade Ring Terminal Lugs Battery Cable Tinned Copper Eyelets
Minnkota 1820089 Charger Output Extension Cable, 15-Feet
3M 5200 Sealant
mounting screws for the battery box
zip ties
14 gauge marine wire, black.


New Tools:
IWISS Battery Cable Lug Crimping Tools Hand Electrician Pliers for Crimping Wire Cable from AWG 8-1/0 with Cable Cutters-Thickened and Reinforced the Metal Plate!!

Schematic:
I went ahead and ran 2 separate lines from the 2nd battery to the switch and the ACR and put the breaker for the 2nd battery as close to it as was feasible.
I also had to run a long ground from the starboard side to the port battery gnd.

I considered connecting the ACR to the switch lugs with the breakers in between the switch and the ACR, but there is a space issue in the 165 and I just felt like it put the 2nd breaker too far from the 2nd battery. It would've only saved a single run of 4AWG across the boat.

The Process:
basically run everything and connect as directed in the schematic. sounds simple, right?

For my specific install -
(Note that you can do it however and there may be faster or more efficient methods. This was just what I did.)

Part I: remove old switch, run cables to starboard side:
I started by removing the existing battery switch. I took it off to verify that the new switch had the same form factor and mounting holes. It did. So far so good.

mounted ring terminals on 1 side of 2 of the red 4AWG and 1 side of the black.

I bundled the 2 reds, single black and the extension for the Minn Kota and ran them as shown in the pictures, using zip ties and leaving everything very loose so that i could adjust it later. Don't forget to mark the 2 reds so that you can determine which one is connected to ACR because it's the one that gets connected to the breaker on the starboard side.

Checkpoint 1: The cables are ran from port to starboard side and the switch has the same form factor. Call it a night, go eat and have a beer.


Part II: mount the ACR, port side breaker and connect the starboard side feed.

I had eyeballed the mounting locations for both the ACR and the port side breaker. I removed the ACR cover, mounted it and connected one of the starboard side red wire feeds to one terminal. Before you mount the ACR I highly recommend connecting the small lug to the 14gauage with the inline fuse. I had to take the ACR off and remount it because I didn't connect the ground wire before mounting it.


After that I mounted the port side breaker.

Next I cut the wires, added the ring terminals and connected the ACR to the breaker and connected the ACR side of the cable to the battery.

Checkpoint 2: ACR mounted. Starboard side feed connected to ACR. Port Side feed connected to breaker. Cable from battery to breaker connected, but not hooked up to the port battery yet.


Part III: Mount the Charger.
Pretty straight forward here. I traced the charger on cardboard, marked where the mounting holes are and cut it out.

Once I had that I used my trusty sharpie and the cardboard footprint to mark where to drink the holes.

because the thing is fairly heavy i decided to go with bolts through the wood and lock washers. trip to hardware store.

once I had the bolts, I drilled the holes and mounted the charger.

Checkpoint 3: Charger mounted.

Part IV: Install the starboard side battery box and battery.

ok very carefully. tape up the gelcoat. put the battery box on carboard and make a template. use the template to mark the holes with a sharpey marker. verify the bit size matches the screw size. double check it. put the bit in the drill. put drill in reverse. double check it's in reverse. put a piece of painters tape on the bit to mark the depth. triple check that the drill is in reverse. using very little pressure drill the 4 holes with the drill in reverse. once the tape touches. STOP. I did this 3 times for each hole, slightly increasing the bit size each time.

remove the tape. inspect the gelcoat. thank god no spidering. put 3M 5200 in the holes. place the battery box over it and using a screwdriver install the 4 screws by hand.

wait overnight for the stuff to cure.

put battery in box.

Checkpoint 4: starboard side box and battery installed.

Part V: Add the starboard side breaker and finish all starboard side connections.

Mounted the breaker. Find the cable that connects to the ACR on the other side.
adjust it's length and add a ring terminal. connect to breaker. cut another length add terminals and run it between the battery and the ACR.

Adjust the length of the other red and black wires, add terminals and connect to battery.

Don't forget to connect the charger.

Checkpoint 5: Starboard side connections finished.

Part VI: Finish port side connections. clean up.
double check that the ACR ground is connected. Double check the charger is connected. Double check that the ACR to port side breaker is connected and the bolts are tight. Connect the port side breaker to the battery.

Checkpoint 6: It's all f'n connected.

Part VII: Test switch position 1,2, combine.
Start boat in position 1.
Start boat in position 2.
Have wife watch LED on ACR.

checkpoint 7: tested.

Part VII: Write this up and post it in case anyone is interested.

I'll add pictures later tonight.

 

[jb32566]

 

[jb32566]

couple things.
im not 100% happy with the terminal covers. i will replace those and also cover the terminals on the breakers.

I would like to move all the connections on the DC- side to a bus bar. I'm just not sure WTH to put it.

I think the ACR is crooked. I intend to remove it and make sure it's square.

Lastly, I will probably add a LED from the ACR to the dash. Add that to the list of projects.

 

[jb32566]

schematic not from cad program. "personal use of company property is prohibited." plus i didn't have my work computer when i drew it.

 

[DBMainiac]

@jb32566 Okay first of all, amazingly informative post. I'm currently researching to do a dual battery hook up for my 16 AR192. I also want to hook up a dual bank charger and I plan on putting a watertight plug through the hull to the back for that. Can you explain a little bit about the need for the ACR and the circuit breakers. I have seen set ups without either but they didn't have a hardwired dual bank charger, just a clip on when needed.

 

[jb32566]

Thanks for the compliment. I didn't have time to complete it all at once, so I had break it into pieces as best I could.
I can't explain an ACR better than the people at blue seas, so I will just link to their page:
Automatic Charging Relay (ACR) Explained - Blue Sea Systems

Fuses, or in my case a resettable fuse (breaker) are to prevent a fire/shock hazard if there is damage to the wires from the batteries to the ACR, damage to the batteries or damage to the ACR itself. My install followed their "Schematics for Typical applications," specifically 2 batteries, 1 engine with a single circuit.
They have lots of use cases.
Battery Management Wiring Schematics for Typical Applications - Blue Sea Systems

Hope this helps! Let me know if you have more questions.
Happy boating

 

[DBMainiac]

Thanks for the compliment. I didn't have time to complete it all at once, so I had break it into pieces as best I could.
I can't explain an ACR better than the people at blue seas, so I will just link to their page:
Automatic Charging Relay (ACR) Explained - Blue Sea Systems

Fuses, or in my case a resettable fuse (breaker) are to prevent a fire/shock hazard if there is damage to the wires from the batteries to the ACR, damage to the batteries or damage to the ACR itself. My install followed their "Schematics for Typical applications," specifically 2 batteries, 1 engine with a single circuit.
They have lots of use cases.
Battery Management Wiring Schematics for Typical Applications - Blue Sea Systems

Hope this helps! Let me know if you have more questions.
Happy boating

Okay great so it looks like if I am installing a dual bank charger, I have no need for the ACR, only if it is a single side charger. That helps. Appreciate your hard work.

 

[jb32566]

The ACR distributes the charge when the engine is running. At that point you have only one charging source. If you plan to have the batteries completely isolated via a switch, you're probably ok, but if you're using them both at the same time you could have problems.

take a look here:
https://jetboaters.net/threads/scarab-add-a-battery-modification.3135/post-98967
idk if @ScarabMike added an ACR or not, but I preferred to take the safest approach < $100 and a another couple hours work seemed worth the piece of mind.

cheers!

 

[DBMainiac]

Gotcha. Well I was planning on not hooking them up in succession, just having them isolated but maybe this is a better way to go. thanks for your insight