After months of planning, thinking and just plain fretting, the batteries are in and Dauntless is no longer acting like a one legged duck.
How do one legged ducks act you wonder? Without the engine running or being plugged into shore power, we had only a few minutes’ worth of electrical power.
And I’d go to sleep, not with visions of sugar plum faeries (or better yet, leggy milf’s) dancing in my head, but with pictures of wiring diagrams and this and that.
So, having found replacement batteries in Kilmore Quay’s Kehoe Marine last month, they got four Yuasa Cargo Deep Cycle GM batteries that were of 8-D size, with 230 amp-hours each for me. Weighing in at 55 kg, or 115 lbs. each and delivered to the Kehoe boys at New Ross Boat Yard (yes, of course they are related).
Waiting for high tide, when the dock was only a few feet above the floating pontoon, we got the batteries on to the boat without dropping them into the water.
Then, the hardest part physically, getting the old batteries out. Perhaps with the knowledge that we could not hurt them, it took us less than an hour to get them out.
I then spent the next few hours re-configuring how the batteries were connected. I essentially made a positive and negative stud that consolidated the all the connections before they went to the batteries.
My friend Ed had given me a new article about the optimum way to connect multiple batteries that was slightly superior to the way I had the older batteries connected. I had had 8 new battery cables made, 2 for each battery, each 2.3 meters long (about 7 feet). This allowed the four batteries to have the exact same length cable to each from the charging source. By having the same cable lengths, the resistance should be equal and thus each battery should get exactly the same amount of charge.
That took a few hours, with a panicked call to Dave Arnold, the electrical guru (who else would be driving around an all-electric car for the 1980’s!).
His call reaffirmed the use of the existing terminal block and Perko switch that was used to switch the start to the house batteries if needed.
Finally, after 8 hours, I was ready for the new batteries. I rigged an Amstel line around the hand railing to the pilot house, thus we could lower the batteries into the engine room and the only struggle was to pull them into place while lowering at the same time.
Two hours later, all was in place, hooked up and ready to go.
All the boat grounds go to a common terminal, then one large cable to the boat side of the Victron battery Monitor shunt. Then one large cable to another terminal post which has all four negative battery cables.
Positives are similar, in that the inverter/charger, the positive from the alternator and the positive from the terminal block (which has a number of inputs from the isolators and thus indirect from the other battery chargers) go to a terminal post, then all 4 battery cables are attached.
In the next days/weeks, as I physically tie the lines and organize a bit more, I will make a new electrical diagram.
Now, according to my calculations, all the rest of the year should be downhill!
4 thoughts on “The Great Battery Caper”
Would love to see the finished diagram along with the article about the optimum way to connect multiple batteries.
Glad you’re all charged up for your upcoming adventures.
Ok I’ll do both
Nice job, Richard! I did that this season also…all new batteries for house and start. I also replaced an old fridge with a new Nova Kool that’s almost twice the volume and less than half the energy use in the same footprint as the old. Electrically, it makes my boat feel like a new boat. I’ve been out on the hook all week and haven’t seen less than 80% on the batteries. My generator run time is cut down to about 90 mins per day. I hope you see similar results!
I’ve been working on a graph, a scatter diagram, showing voltage versus amp-hours out for the last three years. It already shows my batteries were never as good as I thought they were. This fact was largely hidden by the addition of the solar panels 2 years ago. This also explains why batteries that seemed ok in August, were not ok in October. At 55°N, it’s noticeable.