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dszerlag 12-01-2012 04:46 PM

Updating electrical system
 
I just purchased a 87 Pearson 39 and plan to refit the boat. There is very little equipment on the boat, no batteries, older charger, etc.
I will be keeping the boat on a mooring for the foreseeable future and would like some thoughts, insights on the most practical way to power the boat.
This year I would like to get the basics installed and then be able to add a wind generator next year or so.
My thought is to go with 2 bank, one isolated starting battery and two house batteries. I would like to be able to use solar to keep charged while on mooring and maybe more if doable. I've read so much, including all of Nigel's book and articles but wondering what other people have done. Thanks in advance for any and all info, thoughts.
David

eherlihy 12-01-2012 10:04 PM

Re: Updating electrical system
 
Congrats on the Pearson 39. They are great boats. (Are the decks sound?)

How do you plan to use her? Daysails and weekends require different a charging system than a live-aboard.

To begin, I suggest that you improve/stabilize what you have, before adding expensive wind and solar.

I have replaced the battery charger, and most of the wiring on my '87 O'day. They did not use tinned wire, or adhesive lined crimps back in the '80s. After that, I would add a galvanic isolator (probably none on your boat, as they were not required), and a negative bus. You may also want to add a higher output alternator.

Then, if you are not planning to live aboard, I would add a small solar panel with a MPPT solar charge controller to keep the batteries topped up.

asdf38 12-02-2012 10:54 PM

Re: Updating electrical system
 
There is a ton on here about everything, electrical included.

I'd strongly suggest going with a main bank/reserve bank system generally favored here. That means you don't have a start and house bank, you have a large main bank that's both house and start. The reserve bank only exists in-case, by mistake, your main bank is dead. If you combine this with some automatic charging device such as an ACR relay or echo charger it means that you never have to manually change the battery switch - get on the boat and turn it to 1 - that's it, the relay or echo charger does the rest of the switching.

The best bang for the buck on batteries are golf cart batteries. They're designed as true deep cycles and last the longest in that use (unlike almost anything with 'Marine' on it - even the best 'Marine Deep Cycle' are still designed with cranking amps in mind which hurts deep cycle life)

So it's hard to go wrong with 2 or 4 golf cart batteries. They also have smaller footprints which are often better. I'd avoid using a 'starter' battery for the starter - batteries labeled 'starter', even marine ones are fragile one trick ponies good at nothing except providing cheap starting amps. If your main bank is dead you'll likely want some radio/gps light capacity as well.

A down side to golf cart batteries, and flooded batteries in general is their self-discharge rate. So that's where solar/wind comes in to keep them topped off while your gone.

SI-Series Automatic Charging Relay - PN 7610 - Blue Sea Systems

dszerlag 12-04-2012 06:33 PM

Re: Updating electrical system
 
Thanks for all of the advice. The boat for now will be day/week end maybe some short cruises.. I hope, like everyone else to live aboard someday.
I have given some thought to the golf cart batteries and probably will go with that. The main bank with reserve is new to me so i will have to read up on that.
Solar seems to be the best option right now, trickle for sitting on the mooring but I want to be able to design the basic system so it is upgradeable to panels for hard charging and/or wind generator.

mitiempo 12-04-2012 08:31 PM

Re: Updating electrical system
 
If solar is your main method of charging except when motoring you will want a panel large enough to charge as well as maintain the banks. A larger panel (60 to 90 watts) with a good controller will charge the batteries after a cruise or day trip as well as maintain them at full.

dszerlag 12-10-2012 10:04 AM

Re: Updating electrical system
 
Thanks. I think that is the way to go for right now. Any particular configuration you can recommend? I am basically starting from scratch. The boat has no batteries, a newer charger, i'm guessing, 20+amps but can handle all types of batteries, not sure if it can charge more than one bank.
A few on this board have already recommended going with golf cart batteries and using only one bank with ACR relay.

Stu Jackson 12-10-2012 01:44 PM

Re: Updating electrical system
 
These should help:

Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: Basic Battery Wiring Diagrams

This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
1/BOTH/2/OFF Switches Thoughts & Musings - SailboatOwners.com

Golf Cart 6V Battery Wiring Golf Cart batts re-positioning & wiring diagrams

They discuss the different types of charging relays so you ONLY need to run BOTH the alternator output and ONE shorepower charger output to the house bank. An echo charger would be the best way to go for you, or the ACR or a Yandina combiner.

chucklesR 12-10-2012 04:59 PM

Re: Updating electrical system
 
Regarding solar panel selection - throw away the idea of a 60 - 90 watt panel. That's fine for a short weekend but will only make you 30 -40 ah of charge a day. For most folks that's like camping, it won't support even a small 12v refridge unit.
Figure where you can hang the panel(s) (arch, davits, bimini, where ever) - then go for the largest panels you can fit there. 300w+ panels are out there - and they will fit a davit with a little thought.

Do spend the money for a MPPT controller, they really do provide an up to 35% increase in amps to the battery. Outback's are good and reasonable in price (still expensive though)..

Measure out your current battery bank space - good large capacity 6v GC batteries are taller than even Group 31 12v batteries. A pair of Trojan 145's will give you 290amp hours in a smaller deck footprint than a pair of Group 31's, but you have to have the height or it's a moot point. The truly important part is to get as much as you can given the footprint you have to put them in. If three 12v's fit and yield greater capacity than only 2 6v's that fit it's a no brain-er. Stick with lead acid unless you are 100% certain you can get AGM's up to 100% of charge at least monthly.

Find anywhere you can near the engine where it is coolish and put in the largest 12v deep cycle (you heard me right, not a starter). That's your back up and normal starting battery. Charge both the house and starter through an ACR.
Save the 20 amp 110v charger for those infrequent days at the dock - after all when you are there you'll have at least a day so up sizing that is a low priority.

After hauling in the anchor on a 39 footer a couple of times you'll start looking at a windlass (or a chiropractor), after sitting in the cockpit a couple evenings watching the sunset with a warm beer you'll be looking at a good fridge that makes ice.

The first time you are up the mast swap out that power drain we call an anchor light for a LED version. The old ones draw 1.2 ah or more and can suck a battery dry while you sleep.
Don't forget to add a good battery monitor to the mix (Victron BMV 602s for example). Hard to know what's going on without one.

You can always live frugal once you've installed the luxury, but not the other way around.

Maine Sail 12-10-2012 05:31 PM

Re: Updating electrical system
 
Quote:

Originally Posted by dszerlag (Post 955645)
I just purchased a 87 Pearson 39 and plan to refit the boat. There is very little equipment on the boat, no batteries, older charger, etc.

This can actually be a good thing as it allows you to start from scratch.


Quote:

Originally Posted by dszerlag (Post 955645)
I will be keeping the boat on a mooring for the foreseeable future and would like some thoughts, insights on the most practical way to power the boat.

Your alternator should be used to get the bank back to 80-85% state of charge. From there you will want to use solar to "top up" during the week when the boat is sitting idle. Getting batteries back to 100% SOC is perhaps the most important aspect to longevity. Chronic undercharging is what kills most batteries on mooring sailed boats because alternators alone rarely if ever get a battery bank on a sailboat back to 100% SOC. The article below should help.

Installing A Marine Solar System

If you don't have much space for a panel consider a Solbian panel on a bimini.

Installing A Solbian Solar Panel

Quote:

Originally Posted by dszerlag (Post 955645)
This year I would like to get the basics installed and then be able to add a wind generator next year or so.

Wind will depend entirely upon where you are located. Solar very often outperforms wind in many ares of the US.. There are only three wind gens I would even consider installing. The Airmaax, the D-400 and the Superwind and they are all quite expensive, but you get what you pay for.


Quote:

Originally Posted by dszerlag (Post 955645)
My thought is to go with 2 bank, one isolated starting battery and two house batteries. I would like to be able to use solar to keep charged while on mooring and maybe more if doable.

Again read the article above for solar. It can be done very reasonably. A charge management device such as a Echo Charge, Balmar Duo Charge, Blue Sea ACR or Yandina combining relay will all work very well to keep the start battery topped up.



Quote:

Originally Posted by dszerlag (Post 955645)
I've read so much, including all of Nigel's book and articles but wondering what other people have done. Thanks in advance for any and all info, thoughts.
David

There are many ways to skin the cat but suffice it to say, within reason, you can never have too much battery capacity.... Also a battery monitor will be some of the best money spent..


Installing A Battery Monitor


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