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  Topic Review (Newest First)
06-05-2013 03:54 PM
Alex W
Re: Power Battery Set up for 27ft sailboat

Yes, you can buy replacement LED-based bulbs for incandescent fixtures. If it is the original light fixture (and decades old) then going to a new LED-based fixture is best.

Overpowered is bad in both being expensive and heavy.

Incandescent anchor lights can use as much as 20 watts (~2 amp hours, or 25 hours on a single G27 battery). LED ones can be as low as 1 watt (600 hours on a single G27 battery).

This is what I upgraded to:
2 NM NaviLED 360 All Round White Navigation Lamps - Navigation Lamps, Anchor / All Round White - Hella Marine
06-05-2013 03:52 PM
Re: Power Battery Set up for 27ft sailboat

When I purchased my 28'er, the PO had two dual start/house batteries, both about 5 years old. The existing charger was the old style single stage charger and quickly cooked the batteries when left on, even overnight. I replaced both batteries with deep cycle group 27s and replaced the charger with a three stage charger wired directly to each battery. I use this set up for engine starting (Atomic Four), tiller pilot, lights, stereo and VHF. I randomly alternate which battery I use but after starting on one, switch to both after the ammmeter settles to less that 30 amps under the rationale that the starting battery needs the rapid high amp recharge and that both need the lower amp top off charge. Two <$100 wet cell group 27 deep cycle batteries will last more than 5 years, if cared for. However, maintenance free sealed AGMs would be a pleasure to have for just a few $s more.
A Guest 10 amp dual battery charger and two group 27 house batteries will cost just over $300 and give you about 100 useable amp hours, which has been more than enough for me.
ps. for sure, your engine will start with a deep cycle house battery, so you don't need a dedicated starting battery.
06-05-2013 03:19 PM
Re: Power Battery Set up for 27ft sailboat

for now im not sure what type of lights are up there. we just purchased the boat several months ago.

I understand batteries are not cheap but being over powered is not a bad thing in my eyes.

Is it an easy task to change over the running lights to led?
06-05-2013 03:15 PM
Alex W
Re: Power Battery Set up for 27ft sailboat

More batteries is not cheaper.

What is the power consumption of your running lights and depth fnder? You can then figure out the battery capacity needed.

You can probably upgrade your running lights to LED for less than the cost of adding a second or third battery. LEDs are approximately 10x more efficient, it's a big deal.
06-05-2013 02:23 PM
Re: Power Battery Set up for 27ft sailboat

im running a single group 24 and it keeps dying. I have a second group 24 that dies also. Time for new batteries. I want the most economical reliable battery setup for over night - 3 day trips so we can run stereo depth finder and running lights the whole time.
06-05-2013 02:19 PM
Alex W
Re: Power Battery Set up for 27ft sailboat

That will work, but that is extreme overkill for what you've described as your needs.

On my Catalina 25 we had two group 24 batteries in parallel (for a combined 150AH). They've never been plugged into shore power and charge off of solar and the tiny inboard alternator. Even with 12 days of cruising we never got below 80% state of charge.

I'd start with a single group 27 battery (about $100). If you find yourself needing more than get a second. 3 batteries with no fridge is overkill for an outboard boat.
06-05-2013 02:02 PM
Re: Power Battery Set up for 27ft sailboat

I am running a 8hp 4 stroke electric start outboard, depth/fish finder, stereo and running lights.

We rarely use interior lights as we are afraid to have no battery left. Sounds as if my deep cycle is dead. I am thinking of buying 2 6v trojans running parallel and 1 12v deep cycle for engine with a built in charger as our boat is docked at a marina with power each night.

Will this work?
06-05-2013 01:38 PM
Re: Power Battery Set up for 27ft sailboat

Originally Posted by Alex W View Post
Is the OP's 27ft boat inboard or outboard? .
Outboard... unknown if a charging coil/alternator is part of the picture.
06-05-2013 12:18 PM
Alex W
Re: Power Battery Set up for 27ft sailboat

Is the OP's 27ft boat inboard or outboard? If it is an outboard boat then there is no reason to have the complication of a starter vs house battery bank. Just have a single bank (or maybe even just a single group 27 battery if electrical needs are low). If the battery dies you can always pull start the motor.
06-05-2013 11:54 AM
Re: Power Battery Set up for 27ft sailboat

Originally Posted by chef2sail View Post
So you don't have a dedicated battery charger hooked into the batteries?
I was under the impression the float charge is different between the two types. Also how do you equalize and desulfate unlike batteries?
As I said above, both the solar panel and the shore power charger are wired to the main (golf cart battery) bank. The Yandina combiner limits the voltage to the AGM battery (bank). I rarely use the shore power charger, and the charge controller on the solar panel limits the voltage once the main bank is charged. The controller does have an "equalize" mode that kicks in once a month, but this doesn't matter to the AGM because it's "shielded" behind the combiner. I suppose that the AGM does experience higher voltages than it probably should for short periods, but this doesn't seem to have much of an effect, since the AGM is six-years-old now and seems to be fine (although the entire system has only been in place for two or three years). In any case, the AGM shouldn't need desulfonating since it's almost always fully charged.
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