I have been researching dual battery systems and power distribution systems on IH8MUD for awhile and I am now ready to install my own. Thanks to everyone who has posted their projects for the rest of us to learn from. This first post is my plan and I will follow up with pictures as I go. Hopefully this project will begin in a couple of weeks so if anyone has suggestions or lessons learned then I’m all ears.
After finding this Blue Sea Systems power distribution design centered around their SafetyHub device,
Systems Gallery - Blue Sea Systems,
I used many ideas from this forum and consulted with a couple of electrical engineer friends of mine to come up with the following concept for my vehicle:
View attachment 918229
Here are the planned components:
- IBS Dual Battery System with Relay Booster Module. While the kit does not come with fuses for the Battery Monitor wires, I decided to follow my electrical engineer friends’ advice and will add them. The IBS installation instructions mention using 6A fuses as an option. I traded emails with Beat (pronounced Bay-at) at IBS and he said there would be no problem including 5A fuses on those lines. He said they used to provide fuses but no longer do. George, at Extreme Outback, told me that if there was a short in those lines without a fuse they would likely melt quickly and not create a hazard because they are so thin. In the unlikely event of a short, I’d rather blow a fuse than melt the wires so I will install the following in-line fuse holders from Blue Sea Systems, Waterproof In-Line ATO/ATC Fuse holder - Blue Sea Systems.
- Blue Sea AMI/MIDI Safety Fuse Block at the Main Battery positive terminal with a 200A fuse, AMI / MIDI Safety Fuse Block - Blue Sea Systems.
- Blue Sea SafetyHub 100 Fuse Block in the engine bay next to the Auxiliary Battery, SafetyHub 100 Fuse Block - Blue Sea Systems. The two batteries will be connected through this device using a 200A fuse. It will also feed the two fuse blocks in the vehicle using a 125A fuse on each wire. The wires to the fuse blocks will be 2 AWG. The four low power outputs can then power engine bay accessories. I have no requirement for a large air compressor to run air tools, so one of the low power outputs should be sufficient for an onboard air compressor used to inflate tires.
- Blue Sea m-Series Mini Dual Circuit Battery Switch, m-Series Mini Dual Circuit Battery Switch - Red - Blue Sea Systems. This will provide an ability to disable the two fuse blocks if desired.
- Two Blue Sea ST Blade Fuse Blocks – 6 Circuits with Negative Bus and Cover, ST Blade Fuse Block - 6 Circuits with Negative Bus and Cover - Blue Sea Systems. One will be installed in the front cabin and one will be installed in the rear compartment. The Blue Sea wiring diagram for this device shows a 125A fuse on the input, that is why I will put the 125A fuses in the SafetyHub 100 leading to these fuse blocks. Originally I had planned to run low power lines from the SafetyHub 100 in the engine bay to the forward cabin to power radios, but SanDiegoCruiser recommended putting a fuse block in the cabin to make it easier to add more toys in the future. That made a lot of sense so that’s what I’m doing, thanks Craig. I don’t have all the accessories shown in the diagram yet, but it’s only time and money to add stuff… My priority list of accessories is:
- ARB Fridge
- CB Radio (I know it’s old school, but my non-MUD friends still use CBs and I have one sitting in my garage ready to go)
- Onboard air compressor
- Power outlets (12V and USB)
- Rear hatch lights
- A ham radio when I join the club
This will be my first DIY electrical job so if you are learning by doing like me, I found these articles to be helpful:
http://www.bluesea.com/support/articles/Circuit_Protection/1437/Part_1:_Choosing_the_Correct_Wire_Size_for_a_DC_Circuit
http://www.bluesea.com/support/articles/Circuit_Protection/1441/Part_2:_Select_a_Fuse_and_Fuse_Holder_For_Your_DC_Product_Installation
I think that’s about it for now. Hopefully folks will find this posting useful. P.S. in case you are wondering how I did the drawing, I used Microsoft Visio.
