Battery life and charging.

John;

In reading your posts, I can empathize. When I bought my E-34 seven years ago, the batteries would only last about two hours, then it would be necessary to run the engine for two hours to get another two hours of battery life. A vicious cycle for distance races and cruising.

I completely redesigned the system and have had excellent results over the last six years.

Below is an old post which outlines the components I used. I hope this helps, time has proven this to be a great systems. All three batteries still test to 'new' levels - I can still sail for three days, engine free - even after (now) six years, though I do now run the engine while using the microwave.

Best regards;

Steve



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Todd;

Four years ago I upgraded my electrical system on my 1978 E-34. It was quite an adventure. The original Ericson system was terrible.

The old system was two group 27 batteries with a Perko 1-2-Both switch. One battery was always reserved for starting, the other for house. The system requiried almost equal an hour of charging for each hour of battery use - and it was necessary to replace one of the batteries every two years or so.

Warning: I work in electronics, so I got a little carried away with this!

First you must determine average current draw. This is done by multiplying the amount of time each appliance will be used by it's current draw. I used a spreadsheet for this. Then you decided how often you are willing to recharge your batteries. This leads you to the amount of Amp-Hours you must provide, but there are inefficiencies which must be accomodated before you size your battery banks. The biggest factor is that batteries should only be discharged to about 50% of their rated capacity - so you have to double what you thought you needed. Other inefficiencies include voltage drop over wires, current leakage in the charging system and appliances, and resistance in connections.

In my case, I needed two size 31 AGM batteries (210 Amp-Hours) to be able to sail the Chicago-Mac without running the engine. An additional size 24 battery was reserved for engine starting.

Next, you need to have enough alternator to provide the charging current at a high enough rate. I chose a Balmar 100 Amp alternator and a Balmar three-stage regulator so that I could charge the 50% discharged battery bank (105 Amps) in 2 hours. Another subtle little point is that battery capacity is inversely proportional to the currnet load it must provide. In other words, a 100 AH battery will provide 100 Amps at a current draw of 5 Amps per hour - but if the battery is loaded to provide 50 Amps per hour, it will not even last that hour.

So you also need a monitor that will keep track of not only how much cirrent you draw, but how fast you draw it. The Link-10 from Heart Interphase is a great device for this application.

In order to ensure that all that charging capacity was transferred tot he batteries - rather than dissipated as heat in small wires and old switches, I replaced all the corroded, undersized old copper wires with Ancor tinned #1 AWG wires. And just for a little extra safety, I isolated the batteries positive terminals with 135 Amp circuit breakers (as is required on commercial boats that must be inspected).

Finally, I followed the advice of the West Marine advisor and installed seperate switches for the house and engine banks. The thinking here is that there is no chance to accidentally run down the engine battery since it is not even connected to house loads. An emergency cross-over is included so that it is possible to start the engine from the house batteries in an emergency.

Since I keep Rogue on a mooring and do not have regular access to shore power, I installed a small 5 Watt solar charger just to top off the batteries during the week. For occasions that I do use a slip and can charge the batteries, I installed a small 10 Amp Xantrex true Charge unit.

The result - Even with four years on the system, I can still sail for three days without running the engine. We are not shy about using battery power. We run the computer all the time, watch DVD's during the off watch, run a microwave to cook meals for a crew of eight, an listen to a lot of CD's. Also my battery banks test at full (new) capacity. I don't expect to have to buy batteries for another 15 years.

If you want more information, feel free to email me directly.

Regards;

Steve
__________________
Rogue - Chicago

John - A grp 31 battery is a little longer and taller than a grp 27. 13"l x 6 13/16"w x 9 7/16"h. Some people make a big deal out of the bigger size, but it has less than 10% more amp-hours, 115 vs 105 ah. You can make up the difference by discharging to 55% which would have a negligible difference on life. The last time I bought batteries the cost did not justify the larger capacity.

BTW, grp 27 batteries should be rated at 105 ah, not all are. [WM and Interstate, can you hear me].

If you get a starting battery you can parallel them into one house bank and then you only need one monitor. There is no point in having a monitor on the starting battery as starting uses very little energy. Most of us start using the house bank and only have the starting bank for emergencies. The Link 10 is very good and cheaper than it's replacement, the XBM, which has features you won't use.

A last thought: The advice here is worth just what you pay for it. Some of the posts sound a little like snake oil peddlers.

Tom Metzger said:

A last thought: The advice here is worth just what you pay for it. Some of the posts sound a little like snake oil peddlers.

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Nothing personal, but care to explain that? He asked for advice and he got it. Sure, some dissent exists in exactly what and how the upgrades should be performed however I see no maliciousness in any post....

RT

Ah - Touchy today. I didn't imply maliciousness.

The snake oil peddler was an historical and folkloric figure of the American Old West, often featured in Western movies: a traveling "doctor" with dubious credentials, selling some patent medicine — such as snake oil — with boisterous marketing hype, often supported by pseudo-scientific evidence. Less scientifically, but perhaps even more effectively from an immediate sales viewpoint, an accomplice in the crowd would often 'attest' the value of the product in an effort to provoke buying enthusiasm. The "doctor" would prudently leave town before his customers realized that they had been cheated.

It seems to me that people are recommending a system that would keep a continuous cruiser going forever, rather than an improvement for a weekender who has been getting along, barely, on two grp 24 batteries.

We all love the system we built, but it isn't the best system for all, and frequently isn't the best system for our boat.

Examples - An isolation transformer @ $400. Or a 40 amp Xantrex charger when he already has a charger.

Touchy? Not really, just don't like being implicated in "selling" anything. The fact that jkm stated the zincs were being eaten off the boat when it was plugged in is reason enough to warrant a galvanic isolator or better yet an isolation transformer. This advice goes quite beyond the original request however it just makes sense to address a possible serious electrolysis problem.

I would take issue with using an old type battery charger. Admittedly I am unfamiliar with the existing type however if it is old, possibly original then it will not charge batteries as efficiently nor will it offer the overcharge protection that new chargers offer.

I would find it hard to believe that anyone performing any of the upgrades mentioned would feel "cheated" afterwords. I hardly see how an upgraded alternator and battery bank, etc. would be considered applicable to continuous cruising only. It is a 35ft sailboat after all and not a 22ft daysailer. RT

I want everyone to know that I greatly appreciate the input. All wise and it is true the scale goes from the least expensive to more expensive.

This is what I need because only I can choose what is right for me. All advice is culled. Interesting even Rob last post present another issue about the quality of the charger.

Nonetheless I have discovered two things. The 35's icebox is pathetic in the layer of insulation that was sprayed on by the factory. I slipped a mirror under the sink wall and saw it. Despite my efforts inside the box I must now spray in expanding foam, lots of it. I'm going to avoid Howards method and go thru the undersink area and thru the drawer walls FIRST. I've insulated the inside of the box and I hate to violate the stock appearance of my boats elements. Though his cooler is pretty damn outstanding.

My Leece Neville alternator puts out about 20 amps at 1000 rpm, though the motor probably idles at 750 rpm so at 75 degrees f I'm probably charging 12 to 14 amps an hour. Pathetic.

Tomorrow I'll see if I can bump this up with a change in pullies-I'm not holding my breath.

Say I only go to the type 27's $ 60.00 each at Costco 115 amph each it would take, using the 50% rule about 10 hours to recharge my batteries-can't go that long without a beer.

So...
1. upgrade to 27's
2. sneaking in a 24 as an emergency start battery (this could outside my system and chargable at the slip only.)
3. Get a Link 10 to monitor what's going in and out.
4. Check out high output alternators and solar panel/wind generator-weigh their costs.
5. Then if I go with a new alternator, check out the charger (I'm assuming the juice from an alternator goes through the charger first or is it only important when getting 110 shore power?????????)
6. If the charger is unimportant that what becomes important is getting the passive systems to the batteries.


Most important is the galvanic isolator. I think this is so important I'll pay the freight for a new one. Where does it go??

Please critique my thinking.

John

jkm said:

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Most important is the galvanic isolator. I think this is so important I'll pay the freight for a new one. Where does it go??

Please critique my thinking.

John

Click to expand...

The one I installed went between the incoming power receptacle ground terminal and the ground wire going to the distribution panel.

I've been following this thread and was surprised to see the reference to sales people known for their dishonesty, aka "snake oil peddlers". The remark was offered without specificly naming anyone though it was clear that multiple targets were intended. I think that was an unfortunate analogy choice especially considering that none of the contributors to this thread have anything to gain financially by offering their solicited advice, nor are they using a confederate to endorse their recommendations.

I do hope that amongst our user community in the future we can disagree without resorting to insults.

Neal

If the isolator goes after the shore plug then it needs to be before the distribution panel-right?

On another matter:

We all have bad days and as RK said "can't we all get along"? I myself had to go to my neighbor tonight and eat crow over a stupid disagreement we had.

I've come to really admire some of you old salts and don't want a thread of mine contaminated. Lets all back of and forget it. After all we all are Ericson lovers.

How is my thinking on my previous thread??????

John

A galvanic Isolator does indeed connect between the power recepticle and the main distribution box, (the green wire). Remember, it is not switched nor is there any overload (breaker or fuse) protecton; and it's case must be connected to the grounding bus. Also remember, your insurance surveyor will love you.

jkm said:

Neal

If the isolator goes after the shore plug then it needs to be before the distribution panel-right?

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Hey John,

Yes, that is correct. The instructions for mine specifically said to attach it to the ground terminal on the incoming power receptacle and then the other end to the ground wire that was previously on the terminal. Of course when you get around to buying one you will need to follow the instructions for that unit.

jkm said:

On another matter:

We all have bad days and as RK said "can't we all get along"? I myself had to go to my neighbor tonight and eat crow over a stupid disagreement we had.

Click to expand...

After observing the bytes flying I felt compelled to respond for the sake of the innocent. Now that's out of my system and I'm no longer in such a riotous mood.

And I for one have long thought that you should spend much less time with your neighbors and much more on your boat. Heck, move onto the boat on a mooring and you won't even have neighbors !

jkm said:

I've come to really admire some of you old salts and don't want a thread of mine contaminated. Lets all back of and forget it. After all we all are Ericson lovers.

Click to expand...

Indeed !

jkm said:

Neal
...
How is my thinking on my previous thread??????

John

Click to expand...

Ok, I'll go for it now that you've calmed the waters.

Here's my two bits.

jkm said:

1. upgrade to 27's
2. sneaking in a 24 as an emergency start battery (this could outside my system and chargable at the slip only.)
3. Get a Link 10 to monitor what's going in and out.
4. Check out high output alternators and solar panel/wind generator-weigh their costs.
5. Then if I go with a new alternator, check out the charger (I'm assuming the juice from an alternator goes through the charger first or is it only important when getting 110 shore power?????????)
6. If the charger is unimportant that what becomes important is getting the passive systems to the batteries.

Click to expand...

First I say get the #3 Link 10 and take some measurements for more data to set your expectations before you decide which battery size to commit to.

On #1, I would not choose the wet cells that you prefer. While they are low cost they do not like vibration and g-forces, emit hydrogen, need to be nursed, and have a much higher self discharge rate. This combination of features increases probability of earlier failure in your marine application. Instead I would look into AGM. Though significantly more expensive I think you will find reliability and longevity will increase in the marine environment. Another plus is that they can be mounted at any angle except inverted which may help installation. FYI - the AGM choice itself could mandate a new shore charger and alternator regulator.

#2 is a good idea except I would upgrade that one battery to the same size of the house batteries so you can parallel them for charging without issues. Battery manufacturers do not recommend paralleling batteries of different capacities. Now if you do switch to AGM you'll need to make this one an AGM also. Oops, more bucks committed up front.

For #4 I like the idea of the solar charger considering that you don't plug in much. Of course you need to weigh that against your cruising power demands which the alternator is going to address much faster. On the solar output you're probably talking about 6amp output total so that's at most 30-40 amp-hrs per day on a good day assuming the things are actually pointed well at the sun. With the panels you'd need yet another regulator.

On #5, the alternator output likely does not go through the 110V shore charger. Instead the alternator either has an internal regulator or an external one connected to it's output. The Link 2000R is a modern battery monitor which also has a regulator. I'm not recommending that since it's pricey but just pointing out that it is possible to regulate shore charger and alternator outputs with one regulator.

On #6, your shore charger sounds obsolete with respect to charging discipline. I would confirm that and if so look for a good, durable three stage marine charger programmable for your battery type. The old one likely is very heavy and will make a good doorstop.

The AGM portion of my recommendation does inflate costs considerably. However comparing AGM and wet cells is like comparing apples and oranges so it's really a system quality issue for me.

John - I'll try play nicely.

To comment on your list, items 1, 2, & 3 are right on the money. Two is the right approach because, unless someone repealed ohm's law, batteries charge according to need, not the label on the case. Batteries do not have to be the same size to charge in parallel. This assumes that all of the batteries are of the same type, flooded, AGM, or gel. I recommend flooded cells because of cost and availability. The advantage of AGMs on boats is that you can charge them faster, but the reality is that we don't have that ability because of alternator and charger limitations along with the wiring. The other advantages are mostly advertising as the flooded cells work well in boats. Think Ronco. Damn, I did it again. I am not sure that different brands of AGM should be charged together as some use significantly different designs.

My thoughts on item 4 are that you should do a little checking on your alternator wiring before looking at spending any money. You may be able to get the improvement you need without going to a new alternator. I am not familiar with the wiring on A4s, but I am familiar with Universal diesels and suspect that the alternators are wired the same. That is to say that the output of the alternator goes to the instrument panel ammeter and then to the battery switch and batteries. The wire on the diesels is #10 and has a long run which drops the current going into the batteries considerably. Some years ago I posted on this site under "Owner's Projects" a fix for this problem. It's titled "Universal Diesel Engine Mods" and you want "change A". Essentially what it does is direct the alternator output directly to the battery by using the large wire on the engine starter solenoid.

Since you are using shore power I would not consider wind generators or solar cells. A wind generator will annoy you and your neighbors (noise :hoppingmad: ) and the solar cells will clutter up you handsome boat with not much output. Both are primarily for cruisers or moorings. Think that much more hair in the scuppers.

Items 5 refers to the charger, and, while unfamiliar with your charger, it sounds like a manually controlled charger which is not very efficient if you aren't sitting on the boat monitoring the charging. It doesn't mix well with drinking beer. Both under charging and over charging shorten battery life. If it puts out 13.5 volts on a steady basis it is acceptable if given enough time. That's where the battery monitor comes in. A three stage charger is best for what we want on a boat. I like Xantrex or Charles and dislike ProMariner and Guest from experience. The charger and alternator are wired separately as others have said.

Item 6 went away.

I am in agreement with Tom here. I run 2 group 31's on my house bank Gels . Xantrex programmable alt regulator, 80 amp alt., Xantrex True charge 20amp ac charger, echo charge combiner, group 27 starting battery gel , link 10 monitor. All new wiring and circuit protection. I would like to add the galvanic isolator but have found it a lot cheaper to simply unplug the boat once things are charged. My fridge (adler barbour) runs roughly 50% of the day at 5.5 amps so 66 amp hours. By far the biggest consumer. Adding LED cabin lights, running lights and anchor lights cuts the draw a lot, its like better insulation on the fridge. If you are just a weekend warrior I would advise a similar set up to mine it has worked great. I monitor the link and keep my depth of discharge to 50% max. It does not require me to run the engine much more than I normally do just getting where I'm going. By simply upgrading wire to tinned wire of sufficient guage and shortening the runs where possible you can make huge gains. I run the alt. output directly to the house bank + not through the starter and battery switches. It is fused. I used the Blue Seas panel for parralleling in an emergency and I use the echo charge to combine the house and starting bank when charging. A 20 amp ac charger is plenty big for your boat. Wind generators and solar panels are not needed in your case. Galvanic isolator would be nice but its a lot cheaper to simply pull the plug. You should be fully charged after a weekend of cruising by being plugged in overnight. One more thing on battery types, I dont like wet cells because of the hydrogen emmissions and ability to spill acid in your boat. I prefer AGMS becuase of the faters charge rates provided you have the equipment to charge them that way. Gels are a nice compromise in that they are sealed batteries which will not leak acid even in a knockdown situation. They can be charged faster than wet cells (again assuming you have the right equipment namely high output alternator and progeammable regulator) but not as fast as agms and they are priced in between wet cells and agms.
No comment on the snake oil talk other than to say this is an open forum where you will get advice from people who have various opinions and experience levels. If you really want to learn this stuff pick up Nigel Calders books and have a go at it.

Ted - A couple of people have mentioned unplugging their boats when not charging. My question is how do you do this when you get back to the marina late on Sunday afternoon and have to be at work the next morning a hundred and fifty miles away? I would think it a hell of a lot more convenient to stay connected.

The admiral likes not having to carry everything cold back and forth, which requires the fridge to stay on.

I ran my alternator to the solenoid because it is six inches away from the alternator terminal, and the existing wire is 1/0.

It should be noted that your 80 amp alternator would not be limited by two grp 31 flooded cells, particularly with an echo charger which I don't recommend. The three step charger prevents most hydrogen generation.

Batteries

John. Chargers work only on 110 volt at the dock and do not have anything to do with the alternator. New chargers have at least 3 stages and safely charge much faster than old ones. They are wired directly to the batteries. If you stay above the 50% discharge and get a good charger, you will only buy new batteries every 5 years or more. And by the way, I used Costco batteries for 9 years, (two sets) and they were fine. The first set were still fine and were only replaced because we were taking a major trip and were nervous about their age. The starting battery (Costco) is still in the (sold)boat after 9 years.

If you do not live close to the boat then you cannot easily unplug after charging and a galvanic isolator is definately the way to go. The reason I did not want to run the alt output to the soleniod is to isolate the house bank from the starting bank. The only thing connected to my starter is my startign battery and thats the only thing connected to that battery. This way there is no chance that the house bank can drain the starting bank accidentally like if someone left the selector switch on both. This also keeps the charging path from the alternator from having to go to the selector switch then to the house bank. The echo charge is a combiner that parralels the house bank with the starting bank only when the voltage is significant to charge. This also prevents the starting bank from draining to the house bank when charging. I would be curious to hear your thoughts against using the echo charge or any combiner for that matter. Everthing I have read lately suggests doing away with the on/off/all switches and simplifying the cable runs is the way to go. My external alt. regulator is programmed to charge gels and uses a multi step algorithm designed for those batteries, same story with the true charge ac charger. I would ultimately like to go to a 6 volt agm house bank configuration that will get my bank closer to 400amp hours in a similar footprint as the group 31's but thats a way down the road after I buy a few more important items like a new dodger...

Am I to understand that you (Tom) leave your fridge on all the time, even when you are not on the boat?

Gentlemen

I've done my homework as you all suggested.

I ordered a galvanic isolater (30 amp) today. I do not want to waste any more time on that upgrade. Thanks for the input on that one.

I do live a short walk to my boat and could unplug it, but I'm getting forgetful.

As you all know this started with my need to have my Norcold plates in my icebox work over the weekend while at Catalina. Say 60 hours maximum, more likely 48.

1. I will upgrade the insulation even more.


Because my existing system works just fine, the only exception is my need for cold beer, so if I isolate that need (no I won't give up the beer) why screw with my existing system.

Why can't I install one of those 4D batteries, which put out about 200 amphours, somewhere and tie it into the shore charger as well as the icebox.

If I leave the dock with the battery fully charged, the plates use about 3 amps an hour, hell I could run that battery down to nothing and have 70 or so hours of continuos use (course the icebox will cycle off and on). Can I can run it down below the 50% rule?

Am I crazy???????

John

Crazy? no, but...

Apparently we wasted a hell of a lot of keystrokes trying to upgrade your system so I could have a cold beer if I ever ventured out to Socal. If you put in a 4D and run it down to zilch you will have the same system you have now. OK it's 200 ah instead of 170, and you will get a hernia handling it every year, but it's not a real improvement. Besides the hernia, what is the difference between a 4D and two 27s?

I'll just assume you are another Socal blond and drop it. :headb: No, don't worry. I'm not coming out there.

Ted - Yes, I leave my fridge on 24/7. We have very reliable power up in the northern boonies. Because the AB has a 10.5v cutout nothing gets destroyed if the power does go out.

The reason I don't like combiners is that the starting battery doesn't need to be charged very often and it unnecessarily slows down the house bank charging . Starting only uses about 1/4 amp-hour which means that you have lots of starts before requiring a charge. The combiner is just one more thing that can go wrong. I charge my starting battery on shore power only. I picked this up from Mike Adler (Adler-Barbour) in a letter to Practical Sailor several years ago.

I don't worry about my 1-2-both switch being left in both because I never use that position. The only time I use other than the 1 position is if I am testing my start battery, maybe once a month when I am away from he dock for several days. The start battery is strictly for emergency use.

I can't argue with your using a dedicated start battery; When I wired my boat it just seemed like another bother. FWIW, I haven't replaced my "unused" flooded start battery after 10 seasons. It is getting due, but there is always another 1/4 a-h.

Changing battery types seems like an expensive hassle. I could burn a lot of diesel charging before I would spend that much all at once.