Spent the off season rewiring my DC system, with working pictures this time!

[AHoy]

When I purchased my boat it had a subpar DC system. One of my 6V golf cart house batteries died which killed the remaining house bank. Before replacing the batteries I wanted to clean up and understand the existing system I had. I discovered lots of issues like multiple power feeds directly off the battery with no fusing, incorrect lug sizes, bad crimps, ground loops, ext. I decided at the point to do upgrade it all.

This is what I started with, not exactly up to ABYC standards:




The top right battery failed. It was only reading approx 4V so I believe I lost a cell. I think this caused the charger to over voltage the remaining bank and eventually kill all of the batteries while charging at the dock


The original batteries were AGM. I considered a few different options but for just day sailing and some weekend trips I couldn't beat the cost of flooded lead acid.


At 70 lbs each I choose to work smarter not harder!



The original disconnect / selector switches had no labels and I didn't really know how they were wired. I followed some wires to try and figure it out and tag them accordingly.


Always good to have a plan especially before taking on a project of this size. I used Vizio to draw my schematics


Bought lots of supplies and a few new tools.


Out with the old!


About half of the old wiring I removed.


I wanted my battery disconnect panel to also include 24 hour bilge circuits and couldn't find anything I liked. I started building my own and decided to add a bilge pump status LEDs, a counter, and an alarm while I was at it. Here is a whole write up on it if you are interested: https://imgur.com/a/E8AHB



The old ground sub panel in the engine room compared to the new. I think it was an original to the boat.


I think the DC panel was home made and it didn't have enough circuits either.


New 24 circuit panel!


Everything looks good installed but took quite awhile with a jig saw and dremel to get just the right fit.


I've actually made some good progress in this picture but I moved the autopilot and instrument server which makes it look really messy here.


New ground bus, can you spot which cable I haven't replaced yet in this picture?


My label maker and wire duct were great investments! Makes everything look so clean!


New batteries in place with FTZ power lugs on 2/0 cable.

[AHoy]

Power distribution bar.


I hate hidden away inline fuses, got rid of them for a fuse panel for the low current loads. Also added a power terminal strip for the cabin lights so I don't have 4 wires connecting to the same breaker.


All the batteries have MRBF terminal fuses and also used one to protect the feed to the DC panel. The smaller fuse block feeds the echo chargers for the starting batteries.


The instrument control hub and auto pilot were moved to an accessible place and the wiring has been cleaned up.


DC panel lit up and finished. I tried to make it so the first row is commonly on circuits when anchored or docked. Middle row are circuits used when sailing, last row is not commonly used circuits.


Everything looks much better. The flat wire in the picture is AC circuits that still need to be cleaned up but the DC system is just about done!

[john61ct]

Nice work, and on the wiring too! 8-)

[longjonsilver]

Looks Great! Thanks for the write up!
jon

[Bermuda Forte]

Nice job. Im in the same boat right now but it looks like you have a lot more wires than I do!

[danielamartindm]

Nice work. 12 volt is such a pleasure to work with. Small wires, a great variety of connectors, and no chance of electrocution

[SailAmore]

Nice work! Thank you for the pictures.

[Greg Mason]

Brings back memories of when I installed 200 amp alternator and had to change almost everything wiring wise. Very nice looking work, heat shrink and proper lugs. Wasn't my favourite job, but probably one I was most proud of. You should be too.

[tek-noid]

Very nice! Where did you get your Visio stencils?

[ferrailleur]

fantastic job...… what an accomplishment..... thanks for your detailed step by step project: very inspiring.

[Cadence]

Looks great. I hope I missed the ends of each wire being numbered.

[Ahmet Erkan]

Looks good.
It seems like one of the echo chargers gets shorted out with a "emergency both" jumper but not the other. Also the bow thruster battery does not get a echo charger. Interesting.
Hope you will share with us the AC wiring diagram as well. I would be particularly interested if you are planning to use a galvanic isolator/s and how you intend to bond the shore power ground and the ship's ground. Also if you plan to jumper the neutrals from the two shore power cables. (ie: not sure if you are hard wiring the two shore power cables in parallel.) I am reluctant to make any recommendations or comments before your schematic reflects the whole system.
Good luck, happy wiring, be careful, and all the best.
Ahmet

[arthur.watson.1]

Truly awesome job! Could you please share with us your principal sources of information and expertise?

[moseriw]

WOW your'e on a good way to success.

A few comments:

never use this bloody plastic electric tape.
Always try to get your wiring airtight = use transparent shrink hoses with glue
Always use blank ring terminals for crimping
If possible use marine grade tinned litz wires
Avoid male connectors, if parts have these solder the cable on it and cover it with a shrink hose with glue




Tips:
mark all your wires with dedicated numbers. You can print them with your inkjet and place it under the transparent shrink hoses.

AC Safety Earth from Shore: Galvanic Isolator
Battery protection and charging: Battery Combiners
On the load side I am using: Battery Isolators


Difference between combiners and isolators?
Combiners have logic to stop charging when a battery is fully charged and continue with the next in row. That is the best and quickest way to charge
Isolators only allow current -> load but not vice versa. Therefore the batteries are not able to charge/discharge each other

Consider an deep discharge protector < 12V on the load side like


I do not recommend any of the mentioned products, Im fine with Victron but I think the descriptions and manuals are what you want to read.

[AHoy]

Originally Posted by tek-noid

Very nice! Where did you get your Visio stencils?

I found a schematic someone had drawn up for a powerboat online and borrowed some of there symbols, I also drew some of my own. If you would like the native file I'd be happy to share!