Battery Setup - 1998 405 Aft Cabin

[km1125]

Are the batteries spaced out as drawn, or are 1, 4, and 5 sitting right next to each other?

[Mikwallace]

Source of the post Are the batteries spaced out as drawn, or are 1, 4, and 5 sitting right next to each other?

No, unfortunately there’re spaced out as drawn. Therefore; at some point, I’ll move all 3 parallel batteries adjacent to each other with shorter cables. Not much rhyme nor reasoning as to current layout. Seems like a Hodge-Podge of batteries thrown in at a whim, “Let’s try this to see if it works?”. I’ve all the necessary tools to make my own cables, so I’ll clean it up.

I’m beginning to think there was some hazard to the configuration, especially with charger wires going to each battery within the parallel group; overcharging, boiling acid, etc, etc.

Thanks for the input!! You guys are a wealth of knowledge!!

[Mikwallace]

Another Follow Up -

In the diagrams I drew, there’s a red & black wire going from the top battery to: ?Helm? On the first drawing, and ?unknown? On the second drawing. I think tonight I found where the wire goes and what it powers. As I was leaving and buttoning the rear stairway canvas I happen to look up and saw a “Puck Light” mounted on the underside of the aft deck roof. It had a switch on it that turns on either a white or red light shining down on the steps. All DC breakers are off, so it’s gotta be wired directly to the battery.

Another mystery solved!

Pic below.

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[km1125]

Good find.

I'd definitely rewire that to an appropriate "accessory" spot with the proper wire protection (fuse or breaker) inline.

[Mikwallace]

Source of the post Good find.

I'd definitely rewire that to an appropriate "accessory" spot with the proper wire protection (fuse or breaker) inline.

Guess I should have mentioned, it does have an in-line fuse on the positive side. Don’t remember the size fuse but I looked at it the other day when I reorganized the batteries. Hmm? 5 or maybe 10 amp glass tube fuse.

It was really handy when I was securing the canvas.

[kgarguilo]

Adding to this thread because it is relevant for my 99 Carver 406:
3 Batteries on Board all LEAD Acid
Switch 1 (1-2-ALL-OFF)
1) Port Engine + Voltmeter, Aft-Mid-Fwd Bilge pumps, CO Detectors, Battery Charger
2) Starboard Engine + Voltmeter, Fwd-Aft Shower sumps, Stereo Mem, Battery Charger
Common- To both Engine Starters and 12V Panel in Salon

Switch 2 (On-Off)
3) Generator Only

The batteries for 1/2 Engine and house 12VDC power are currently Continental TM-27 CCA-625

According to the manual I have the following is known:
#1 Position #1 will use battery number one to power both engines and all other 12 Volt equipment. Battery #2 will be isolated and remained in reserve.
#2 Position #2 will use battery #2 to power both engines and all other 12 Volt equipment. Battery number one will be isolated and remained in reserve.
ALL With the selector switch in “ALL” position, battery one and battery 2 are connected in parallel. Both batteries will be used by the engines and other 12 Volt equipment.
A tip from Carver = Carver recommends using one battery at a time. The only time you should use the “ALL” position is when a single battery is not capable of starting your engines. After starting the engines in the “ALL” position, switch the selector to either #1 or #2 position.

Here is where I struggle. The batteries in this boat are Continental TM-27 the only spec is CAH 20HR = 95 web is https://www.continentalbattery.com/prod ... ne-rv/TM27. So these batteries do not meet the spec requested in the manual of 105 AH. Specifically under battery installation and maintenance it states your boats 12 Volt DC electrical system is powered with Qty 2 105 amp HR batteries.

My limited knowledge of batteries and a conversation with a very smart guy at Interstate battery ( I know people's opinion vary on Interstate I've had great luck) he recommended moving up to a SRM-4D battery Web is https://www.interstatebatteries.com/products/srm-4d this battery has 195 amp hours each. The group 31 M-31SHC Web is https://www.interstatebatteries.com/products/m-31shc has 99 AH but again, not 105.

All the above to get to this question: If I move to a 4D battery I will have to change the orientation of those two batteries from across the vessel to in line with the center of the boat. The size is 21” length which is just too long to fit cross ways on the boat in the battery area in the center of the boat engine room. Does anyone know of an issue with doing this? I am guessing I would need to be on top of filing the batteries for when we are plowing through the water (on an angle) do not allow for dry plates while the engine alternator is charging.

My Charles 5000 three bank charger should be able to handle these larger batteries and charging capacity. Unless you know something that I do not.

Why am I doing this? For many weeks and maybe months in the south we get great temperatures where we would not need the AC on but, would need the fridge to run all day and not run the batteries dry.

All comments help, past experience, failures, war stories, are welcome and appreciated. Hopefully this is very clear. Thanks in advance. Happy New year to all!!

[km1125]

The engines don't really need the amp-hours, but the fridge 's (or other accessories) might if you use it for long hours. I think Group 31's are pretty common in that kind of an application, especially if you have an onboard genset that you can use if you really need the extended runtime of accessories.

Not a real downside to the 4D's though, except the cost and the weight. I would much rather bolt two (lighter) six volt golf cart batteries together and get 205AH if I really thought I needed the capacity (and I did do that for my house battery).

You could even put TWO Group31's in parallel on ONE side of the switch (whatever you want to call "primary" and leave just a single Group 31 on the other side as your "reserve". There's really no reason why both sides of that switch have to be tied to identical battery banks.

That all said, there's no reason you can't put the 4D's in "sideways". If you're running FLA batteries you'll always want to make sure the electrolyte level is correct, so a little pitch as you're getting up on plane isn't going to be an issue. Even if the batteries were a little low on electrolyte, the temporary condition of a plate getting "uncovered" isn't going to amount to much, as it won't really get a chance to dry out, which is where the real damage occurs.

If you don't already have one, you might consider a VSR and wire it between posts #1 and #2, so that your "reserve" battery is always getting a topped off charge from the engines while they're running. Not REALLY critical in your application, because you have an onboard genset and also the charger which I'm sure also tops them off whenever the genset is running or you're fed with shorepower.

[kgarguilo]

You could even put TWO Group31's in parallel on ONE side of the switch (whatever you want to call "primary" and leave just a single Group 31 on the other side as your "reserve". There's really no reason why both sides of that switch have to be tied to identical battery banks.

Great idea and the Group 31 size is preferrable. The 4D will not fit sideways as my opening is 20 3/4" and the batteries are the same size minus a battery tray to secure them in place. A thousand thank You's great idea.

[bud37]

Source of the post #1 Position #1 will use battery number one to power both engines and all other 12 Volt equipment. Battery #2 will be isolated and remained in reserve.
#2 Position #2 will use battery #2 to power both engines and all other 12 Volt equipment. Battery number one will be isolated and remained in reserve.

Source of the post 1) Port Engine + Voltmeter, Aft-Mid-Fwd Bilge pumps, CO Detectors, Battery Charger
2) Starboard Engine + Voltmeter, Fwd-Aft Shower sumps, Stereo Mem, Battery Charger
Common- To both Engine Starters and 12V Panel in Salon

You have brought up some things here that are cause for some discussion IMO.

When there is a need to select a switch position for say Engine Start or House, consider what is hard wired to that position. ...in your case, battery pos. #1 has all bilge pumps and CO detectors.....they are on there own safety breakers and are not controlled by the position switch.

Battery pos. #2 has the stereo memory, which also is hard to its own breaker.....if this is selected it will draw from that battery position regardless of the switch position, same as above.

So you can see these batteries are never really isolated in the true sense as they will have parasitic draws regardless of the selector switch position.. maybe the switch position numbers are still evident on the cables near the batteries.

Another consideration should be how the windlass is powered up....check how it is powered by trying it with the selector switch in different positions......, is it powered thru the selector switch regardless of position ......if so then it will be wise to select the engine start position with the engines running as a windlass requires start type batteries for proper operation.
The modern ECU controlled engines do not like voltage spikes or drops so again here the use of 2 start type batteries in parallel is wise for the engine start position on the switch.

One other consideration will be the old Charles charger....probably in need of upgrading if you are going to upgrade the battery set up......check what float voltage you are getting now or even if it is going to float range for your batteries.....something like 13.2 to 13.6 VDC..........a bad charger can severely shorten the life of a new battery bank.

Good luck with your project.

[kgarguilo]

All, good points. I will look into this today. Agreed that the windlass could be a potential issue. Thanks.