Sharkcat battery setup

[paullee]

Hi Guys,
I have searched on here but can’t find what I need in relation to the way others set up their cats. It’s a recently purchased old cat and we have noticed the current wiring isn’t correct or “best practice”. There is only 1 isolator and the dash only gets power when the sw is in position 1 or “both”. I am a sparky and totally understand wiring but wondering if everyone uses VSR’s on boats these days? I have drawn the below basic wiring diagram without fuses and stuff they will be included later. I have drawn a change over switch for the dash power so if one battery was to go flat you could select dash power according to which battery is in use. I also might suggest he uses a 3rd house battery and but wondering how others do theirs? Thanks in advance for any help. Cheers..Paul
Edit: the plan would be to run 1 motor on switch setting 1 and the other on switch setting 2. Dash setting would only change if a battery failed and needed to run on one battery only and then that battery would be selected with the dash switch.

IMG_1508.jpg

[Brettoh]

I have 3 batteries.
One for each engine and another for electronics and lights etc etc.
I have an isolator for each battery. I also have 2 x parallelling (sp) switches and a DVSR >
You can read about the system here BEP Battery Distribution Cluster - Square | Blue Bottle Marine

Ive one of these 4 gang units and another red and yellow on the other side of the boat.

Its wired up so that I can lose 2 of the 3 batteries and still start an engine and then choose to send power to any of the other batteries at will.

[paullee]

I have 3 batteries.
One for each engine and another for electronics and lights etc etc.
I have an isolator for each battery. I also have 2 x parallelling (sp) switches and a DVSR >
You can read about the system here BEP Battery Distribution Cluster - Square | Blue Bottle Marine

Ive one of these 4 gang units and another red and yellow on the other side of the boat.

Its wired up so that I can lose 2 of the 3 batteries and still start an engine and then choose to send power to any of the other batteries at will.

Thanks Brettoh that’s what I was after. They do another cluster which is exactly what my circuit was.
Cheers..Paul

[Flex]

I highly suggest having a look at Bluesystems gear and Diagrams.

I can highly recommend their 4 pole isolators. So much better to use than standard 3 pole.

In all my cats Id run 2 start batteries and a house.

Below is what i think is best practice as you never parallel up batteries unless in emergency. Unlike most people using 3 pole isolators, which are a pain to manage and you need more isolators to do it properly. 4 pole should be the new standard

can parallel up either isolator if any of your batteries goes flat. Its an awesome setup and simple to install and manage and ensures batteries are kept seperate from one another at all times. (unless needed in emergency)

twin batterie wiring diagram.png