Battery care and feeding

[DougSea]

Last year as Sonny IV sat at the service dock my batteries / charger died. Not sure who killed who but I ended up needing to replace all but the (nearly) new generator battery and I charged everything up with an automotive charger.

Today I finally got around to replacing the charger. I had a ProMariner ProTech-4 but I wanted something with both more "intelligence" and capacity. I recently found a re-manufactured ProMariner ProNautic 1260 C3 on EBay for half price, no tax, free shipping and a guarantee! Plus the seller had a 100% positive feedback rating. Nice.

Naturally the new unit was bigger than the old one so the swap out took just a bit longer than I'd hoped. Still, about 4 hours all in really wasn't bad. I also took the time to do a bit of rearranging of batteries and charger connections.

I have 4 batteries. One group 27 dedicated to the generator, a 4D and 2 8Ds. I always suspected that the House was one of the 8Ds and the engines had a mismatched 4D/8D. I was correct, and have now changed that so that the engines each have an 8D and the 4D is the house.

The other odd setup was the charger. Typical of many chargers both my old and new chargers are 3 bank units. However the boat had 4 charger leads in the battery compartment. Figured out that they (whoever they were) had run two of the banks to the engine batteries, and the 3rd bank went to a Guest Battery Isolator, which split the 3rd bank into battery 3 and 4. In my case the house and the generator.

image.jpg

This struck me as less than optimal. Two reasons. The batteries are of dramatically different size, and they have very different use profiles. On the other hand I have two identical batteries that get almost the exact same usage. So now the 3rd bank goes through the isolator and feeds the engine 8Ds. The generator gets its own bank and the house gets the remaining bank. This should help balance out the charging and, based on my smart charger, help make sure that the house can take advantage of the high charge current available.

Here's the new charger in all it's glory:

image.jpg

As for the feeding.

I'm pretty sure I'm responsible for the death of my prior batteries. Continuing a habit I picked up on my 28 I had a tendency to always turn my house and engine battery switches to position "both", that paralleled all of them together whenever I was running as well as back at the dock. Makes for great cranking power, however, since I would just use the house while on the hook, I would have batteries at different charge levels. Since the charger would see the sum total as a single bank I was overcharging my start batteries.

So, new rule. Each battery will be set to "1", isolated, unless I have a cranking issue. On occasion, if I need to use the engines to charge the house I'll goto "both" on all 3, but that will be the exception. Back at the dock and plugged in the engine batteries will be off (they still get charged) and the house will remain on "1".

I'll be monitoring how this goes but I'm pretty confident I will be optimizing my battery charge profiles and maximizing the life of my leaden friends in the bilge. And that's a good thing!

[mhanna]

Excellent writeup Doug, 4 batteries, 3 banks and a good charging system... You now know your battery / charging system better than the guy who put it in
Does the Protech have a battery "life" monitor also ? I have seen some separate systems that try to give you the Ah, voltage, etc.. for each battery.

I have a question on your comment about killing the battery's on your 28, I also run on both but when at the dock switch to 1, the charger should know what battery gets low and send the extra current to that one and should not overcharge the other..
I have thought about a "smarter" charger for some time but right now nothing is broken so I cant justify doing anything.

Thanks
Matt

[Chris & Dale]

Sounds similar to what I did w/Steel Hers last year. The one additional item I added was the Yandina 100 Combiner. This is supposed to balance use and charge between the 2 banks. Since my charger is working fine and no issues w/my batteries, I have to assume it is doing its job as well. They're not that expensive and just one more tool in battery management. Here's a link to the post:
viewtopic.php?f=27&t=5951
Good Luck

[DougSea]

Thanks Matt!

Will I be seeing you guys at the rendezvous?

Does the Protech have a battery "life" monitor also ? I have seen some separate systems that try to give you the Ah, voltage, etc.. for each battery.

The C3 series has a remote display that gives more information on the state of the batteries, however ProMariner's web site isn't the best and I can't tell from the description just how well it monitors the banks vs. the overall battery setup.

It did come with a temperature sensor (just one) that I'll be adding to the House battery since it's the one most likely to be deeply discharged and therefore taking on a large current inrush.

I have a question on your comment about killing the battery's on your 28, I also run on both but when at the dock switch to 1, the charger should know what battery gets low and send the extra current to that one and should not overcharge the other..

It depends on several things. What kind of charger do you have, does it have true separate "banks" or just multiple leads to the batteries? My 28 had an inverter/charger and no isolator of any kind, so to charge the batteries at the dock they each had to be on.

After replacing my engine start battery (on the 28) I started paying more attention to how I used my batteries and the charger. I should also note that the 28' spent much of the first few years I had her on a mooring so the idea of "cooking" a battery with the charger was somewhat moot.

A typical day on the 28 would be:
-Both battery banks on to start (especially with a cold engine)
-Once running, shut down the house bank to make sure the engine start battery was fully charged
-Once the battery gauge on the dash showed full charge switch over to the house bank and shut off the engine battery
-Get to wherever I was going, anchor, and live off of the house
-When ready to get underway again, repeat the process. (If the house was used heavily, say overnight, I'd just use the engine start battery with the house bank off so it wouldn't suck power from the start.

Bottom line of this whole post - even those of us who should know better don't always treat our batteries properly. We're so used to ignoring the one in our car that we don't think about it.

You can't treat your batteries as a single giant bank. Each bank type (engine, house, generator) needs to be charged properly or you'll greatly reduce the life of your batteries. If you're not sure how your banks and charger are setup, you should try and find out.

Anyway, hope that helps!

[DougSea]

Sounds similar to what I did w/Steel Hers last year. The one additional item I added was the Yandina 100 Combiner. This is supposed to balance use and charge between the 2 banks. Since my charger is working fine and no issues w/my batteries, I have to assume it is doing its job as well. They're not that expensive and just one more tool in battery management. Here's a link to the post:
viewtopic.php?f=27&t=5951
Good Luck

Dale,

Nice project/post! I must have missed that one when I was in my "I hate boats" funk over the winter!!

You did the right thing by using opposite ends of the bank for your connections, the loss of capacity when you parallel the batteries but connect to a single end is amazing. There's a good article with a diagram about paralleling banks of various sizes and the related math out there somewhere in my collection. I'll have to try and find it.

[Serenity]

In regard to the single engine, two battery set-up, what is the recommendation on what battery powers what. My starting battery, #1 a 4D has all of the feeds for powering the electronics, pumps, windlass, and thruster terminated to the positive post. The #2 battery enjoys the company of an auto bilge pump and that's it. I am thinking of moving all of the wiring except the thruster and windlass and perhaps some electronics to the #2 battery. I am going to replace the #2 battery, with a type 27. The old #2 is over 4 years old. I don't like old batteries in a boat! Any thoughts on how you guys have your electrical terminated to the batteries?

[DougSea]

Hey Max,

Here's my view. You should have 1 of your batteries, let's say, based on your post, your #2, sized for your engine starting, and nothing else. There should be no other connections to this battery, and you would use it as I described above.

Your other battery is for your house loads and should be sized based on your expected use. Do you sit on the hook a lot? Run lights, fridge, stereo for hours with the engine shut down? If so, go big. If not, you can go with a smaller battery. In either case it can/should be a "Deep Cycle" battery. These are meant to provide their rated power for extended periods and are not nearly as adversely effected by being fully discharged as your cranking battery would be. This battery will also power an "always on" buss bar that doesn't go through the switch. This is for your bilge pumps, stereo memory, and any other devices that need power 24/7. Please note that the feed to this buss bar MUST be fused, as should all of your (+) feeds.

I don't know what your charging setup is, so I won't comment on that now. Do keep in mind that you have a "at the dock" charging system, and a "engine running" charging system, so you need to pay attention to both.

I hope that helps in getting you started, and I'm sure other will chime in. If anyone disagrees with any of the above, please don't hesitate to comment. I've learned a lot over the years but if you have a proven better way, I'd sure like to hear about it.

Edit - Check out the link posted in the thread below by DessertBoater. It's the 10th post down. Lots of good information. I like the setup the guy describes (in the link) at the bottom, with two switches and an ACR.

viewtopic.php?f=28&t=6399

Best,

[Serenity]

Yo Doug, thanks for the comments. I should be picking up a new deep cycle type 27 battery this afternoon. It appears, as I stated above all of the electrical terminations were made to the starting battery. The house battery only had the mid-ships auto bilge pump wired to it. My intent is to switch all the wiring to the house battery except for the windlass and bow thruster. We don't spend much time on the hook except for day trips. Anchoring on Great South bay overnight would be somewhat hazardous. In regard to a battery only positive buss, that would have to be traced out. As you know on the 28, we have the individual dc panel on the aft bulkhead in the cabin. The main breaker controls the slave switches on the panel but also controls the buss behind the helm. nevertheless, something to do on Happy Daddy's Day. How are you making out with Sonny lV?

[DougSea]

In regard to a battery only positive buss, that would have to be traced out. As you know on the 28, we have the individual dc panel on the aft bulkhead in the cabin. The main breaker controls the slave switches on the panel but also controls the buss behind the helm.

My recollection of the electrical setup in Sonny III's helm was that there were two +12 buss bars. One was tied to the main DC breaker as you describe. The other came straight off of the batteries (don't recall which one). THAT buss bar fed the buss on the helm switch panel that fed the pumps and the memory wire from the stereo was also connected to it.

How are you making out with Sonny lV?

Thanks for asking. Very frustrated. I keep taking the steps the mechanic asks me to check out, with no improvement. He was supposed to get on the boat yesterday and check things out himself but there was some kind of emergency with either him or his staff and he didn't make it. So she sits, listing, at the dock, looking sad...

(She's listing because the entire, heavy, galley has been removed many of its parts are sitting to port.)

I'm headed down there shortly to do one more test they've asked me to do. And to throw a mini fit about the delays in getting the mechanic on-board.

[jleonard]

And to throw a mini fit about the delays in getting the mechanic on-board.

Well the squeaky wheel is the one that gets the grease. So throw a big one.

[RobS]

And to throw a mini fit about the delays in getting the mechanic on-board.

Well the squeaky wheel is the one that gets the grease. So throw a big one.

I agree, time to open up a can of this stuff, what's it been a year now altogether, you could have graduated from Volvo school by now.

[Pitou]

And to throw a mini fit about the delays in getting the mechanic on-board.

Well the squeaky wheel is the one that gets the grease. So throw a big one.

I agree, time to open up a can of this stuff, what's it been a year now altogether, you could have graduated from Volvo school by now.

I've always preferred the envelope of cash the day after the bill arrives.

[RobS]

..I've always preferred the envelope of cash the day after the bill arrives.

Oh I think Doug would have no problem whatsoever opening an envelope of cash the day the bill arrives IF it is for a completed repair.

Nice signature Kev, that's quite an impressive current fleet you have there! You will no doubt have your own envelope on hand this summer (and way too much free time for non-boating chores and honey-do lists)

[Pitou]

..I've always preferred the envelope of cash the day after the bill arrives.

Oh I think Doug would have no problem whatsoever opening an envelope of cash the day the bill arrives IF it is for a completed repair.

Nice signature Kev, that's quite an impressive current fleet you have there! You will no doubt have your own envelope on hand this summer (and way too much free time for non-boating chores and honey-do lists)

Boaters in my storage yard and the marina are always in awe how quickly my diesel mechanic shows up. I tell them he just likes me.

A $ 5,200 slip fee for "the fleet" ... a 9 ft. Zodiac. Rob, I just might clean the basement this summer ...

Wishing you all the best Doug!

[Serenity]

Completed bill or not, when you have to entice a mechanic with green, you are going to get what you paid for. I would prefer his first born as collateral. The downside is one just might inherit the child and have to pay for the wedding, college, graduate program and doctorate. I would go back to Rob's philosophy and whip out the can of "encouragement". Good and responsible boat Mechanics are a rare breed, very rare. The ironic thing about mechanics, it is not the money it is when I get there attitude. The best part is when they say they will be there, don't show up or call.