Batteries? Where, what, why?

berwick · **Joined:** 21 Oct 2006 18:12 **Posts:** 325

I know this is a late thread but I just finished my battery install and thought I would throw another option into the equation. I installed the starter battery (an Optima Redtop spiral - no water required) under the sink and as far aft as possible so as not to lose any storage space. The three house batteries (Trojan T1275, 12 volt golf cart type) are paralleled and fit into the normal spot under the nav seat with only a slight mod of cutting up on the bottom of the wood a couple of inches where the back rest is, this gives me a 450 AH capacity (200 AH useable). Also added the trojan hydrolink watering system which makes it very easy to keep them topped out.

Richard

airedog · **Joined:** 09 Nov 2011 07:22 **Posts:** 69

As our T37's commonly list to port, I didn't want them under the nav station seat, also with wet cells you have hydrogen to consider. So I moved mine behind the engine. I removed the water heater, enlarged the platform to allow the water heater to be moved back as far as possible. Then I tabbed 4 sides as a box base to the platform. built a top for the box. Base and top both 6'. Glassed the inside top and bottom (I glassed the platform first). Drilled vent holes in lid. My bank is (4) 6 volt Duracell from Sams end to end at the rear with a 4D in front. I did keep (2) 12 volt batteries under the nav station, with my 3 bank C-Charles I have the 3 banks separately charged, and to eliminate any complications I have the "emergency" bank not connected to the system. It will be kept charged from shore power. If both banks fail, I'll disconnect a or b and connect the emergency bank. I have lots of pics and will try to get them posted...and if you want measurements I'll post them...as for hardware, I spent $400 on 00 welding cable and ends, plus the batteries and sundries. Probably a boat unit in all. Also was going to use an isolator, actually bought one, but my electrician pointed out they draw a good deal of power and with the er bank configuration it wasn't necessary. I also have a 140 amp alternator.

airedog · **Joined:** 09 Nov 2011 07:22 **Posts:** 69

Here are pics. For sizes ask...as for the width, the base just fits. I had to remove the trim piece on the starboard side and sand off about a half inch to make it work. The platform was installed first, tabbed to the hull and covered with matt and glass. I made the base sides and tabbed them to the base. Made the top and glassed the inside. The platform is built 2" higher (2x2's on the existing base on which the new platform sits). Also (obvious probably) but use a piece of cardboard to make a template for the platform. The water heater is back as far as it can go upon this higher base, which is a bit further back than originally due to height. Finished, the forward edge of the battery box allows enough room to access the shaft coupling, and there is JUST enough room for the baffle (that was funny, I forgot about it, and putting the engine together we discovered it just fits...lol..). As for height, the finished box is 12" high. That allows enough room to crawl over. Actually, it's a nice clean surface to work off of. With the box in place, I shimmied, face up, under to the starboard side instrument panel (which is in the cockpit).

And as I said, I decided to keep the original bank also. Final setup has the (4) 230 ah duracell 6 volt wired in series parallel. Positive in to battery 1. Bridged to battery 2. Negative in to battery 3, bridged to battery 4. Battery 3 (+) to battery 1 (-). Battery 4 (+) to battery 2 (-). Result is 460 ah in 12 volt. That is bank A. Bank B is the 4D (177 ah). My existing bank was (2) 12 volt deep cycle 100 ah. I kept them, connected together (+) to (-). That gives 200 ah backup. They are connected to the 3rd available bank of my C-Charles 60 amp charger, but not connected to the system. If needed, I'll disconnect a bank and connect this emergency bank. I was going to rig a start battery system, but that gets complicated with alternator charging necessitating a battery isolator (which themselves suck a lot of current). This way, when plugged in the er's will be kept charged.

Also, I have 3" holes cut on the back side of the box away from the engine for ventilation.

So that was my solution. I hope the golf cart battery's last as long as they say...also, I have a new C-Charles 30 amp 3 bank smart charger for sale. I bought the 30 for the Tartan and the 60 for the Hinckley. I installed the 30 in the Tartan then removed it and replaced it with the 60. So it was installed but while still on the hard.

T37Chef · **Posted:** 04 Aug 2014 14:40

I am very pleased with my choice of location, and although some say putting a bank near the engine is not recommended, how often is the engine run? And with a blower on I dont feel its going to be a significant factor in a shorter life span for these batteries. The L16 Trojans are huge, and not something one wants to move on their own, I move the boom over the starboard locker, attach the preventer/pulley system and out they come, swing the boom over to the dock and onto a dolly. Really pretty easy. These are tough, long life, thick wall, deep cycle batteries often used in forklifts and similar applications, floor sweepers, etc.

With typical electronics, inlcuding radar, auto pilot, GPS and a 12V fridge, I found running the engine for about an hour using a 120 AMP alternator kept them well above the 50% capacity, usually around 70 amp hours used of 215 usable, total 430 for thr two L16's. Last year I kept a close eye on the water level, this year I have been checking them about once a month or less, oly needing water once...and not much.

I also have one start battery but have yet to switch over to using it so its always ready to go, and just in case, I have a battery pack/hot shot as well.

Anyway, pushing the water heater back and mounting the batteries on a platform positioned on top of the old and extended forward but not covering the shaft was perfect and takes up room otherwise pretty much wasted.

Cheers

Someday I will remember to take a picture

JDLanglais · **Joined:** 27 Jun 2007 11:23 **Posts:** 40

[img]Hello guys;
Here is my battery installation on Nemea; 4 x 6V Trojan T125 for house; 2X 12V Group 27 batteries in parallel for start/windlass use; in original location.
Made a custom battery boxes for 6V out of plywood and epoxy.
No significant port list with the added weight.

Have a great winter !
Jean-Denis
S/V Nemea
[img][/img]

puffcard · **Posted:** 16 Oct 2014 10:30

berwick wrote:

I know this is a late thread but I just finished my battery install and thought I would throw another option into the equation. I installed the starter battery (an Optima Redtop spiral - no water required) under the sink and as far aft as possible so as not to lose any storage space. The three house batteries (Trojan T1275, 12 volt golf cart type) are paralleled and fit into the normal spot under the nav seat with only a slight mod of cutting up on the bottom of the wood a couple of inches where the back rest is, this gives me a 450 AH capacity (200 AH useable). Also added the trojan hydrolink watering system which makes it very easy to keep them topped out.

Richard

Thank's for this post. I was thinking about doing the same thing, but using a very simular 12V XC2 US Battery. I can get them for $145 and he'll take my 31's for a core. Plus he's onle two blocks from the house.

Tartan37.com

Batteries? Where, what, why?

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