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AHoy · 01-06-2018, 07:45

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 · 01-06-2018, 07:57

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!

er9 · 01-06-2018, 08:17

So the power terminal strip for the lights is similar to a bus bar but it connects to the positive coming off the fuse from the distribution panel to power one side of the bar?