Electrical System Questions

[Stella Karuna]

Andrew and the other good folks on Tug Nuts have been helping answer my numerous questions about the electrical system on a 2011 25SC. I am slowly coming to an understanding of it. So I hope the following questions make some sense.

1. I understand that the 150 amp alternator has no smart regulator which can provide 3-stage charging for the batteries. I also think I understand that all the batteries use a combiner which merges the house, thrusters and starter batteries into one big battery when charging.
a. Will this not result in the house batteries being chronically undercharged and the thruster and starter batteries being chronically overcharge since batteries will be discharged to a different degree?
b. Do batteries last longer and accept more charge in a shorter time if they are 3-stage charged?

2.I understand that you cannot mix battery chemistries - AGM, Gel and flooded.
a. Am I correct that you should not mix different internal construction types such as golf cart, deep cycle, starting and dual purpose batteries even if they are all flooded?
b. If this is true, does it mean that I have to add dual purpose batteries for extra house batteries?

3.If I wanted to solve the above problems and increase my house battery capacity would the following work?
a.Balmer ARS-5 3 Advanced Regulator
b. Balmer Alternator and Battery Temperature Sensors
c. Balmer Digital Duo Charge located between the house bank and starter/thrusters bank
d. Replace house batteries with flooded 4x 6V 225 Ahr golf cart batteries.

I have no particular preference for any brand, it is just what I found at West Marine.

Any help would be appreciated.

 

[Andrew Custis]

Hopefully some of this will make sense.

1. The alternator will charge the batteries as you have said. With the blue sea charging relays, they will connect in sequence as each battery bank rises to 13.2 volts. As soon as the batteries fall below 13.2 volts, they will then disconnect allowing them to become seperate banks again. (Your onboard battery charger is a smart charger that is a 3 bank, 3 stage charger.)

The alternator also has a voltage regulator which will not allow the batteries to be overcharged. Lead acid batteries are a bit more sensitive to the voltage difference while being charged. The best thing for your batteries is to not let them get below 11.8 volts as this is the state of a dead battery. 12.8 = full charge. 11.8 = 0. Keep your batteries topped off with distilled water if using a lead acid battery. The other things that are hard on batteries is extreme weather. The hot and cold can really effect the life of a battery. I would be willing to bet that batteries last longer in San Diego than Alaska. 😀

2. That is correct. Use all like batteries. If all three of your banks are group 27, use group 27. If they are all lead acid, use all lead acid. The closest characteristics to a lead acid battery is an AGM. Do not buy Gel as you will have to change the settings on your on board battery charger and they are much more sensitive to charging voltage.

Your boat currently uses a "deep cycle" or dual purpose as the house battery. I would prefer to have all deep cycle batteries as my house bank but they should all be the same. They should also be close to the same date they were manufactured. Best to buy batteries in groups. The exide batteries used in your boat are not top of the line by any means. I suggest using them until they die and then upgrading to a higher end battery group. AGM is my preferred battery type.

As I mentioned on the phone with you, I do not think it is necessary to use the balmar products as our system works just fine. The duo charge is a good setup when adding another bank of batteries to the boat without any other sort of combiner or isolator. If you are adding house batteries, you are not creating another bank of batteries. You are enlarging the current size by tieing the positive and negatives together which would mean you are "paralleling" the batteries. As I also mentioned, I would invest my money in a good on board amp meter which will really allow you to keep an eye on the status of your batteries.

Remember this valuable tip. The blue sea charging relay acts as a combiner and an isolator. As I mentioned above, the combiner will connect the batteries at 13.2 volts but it will then kick in and act as an isolator and disconnect the battery banks if they ever go below 10.8 volts so it will not bring the next bank inline down to its capacity.

 

[Stella Karuna]

Thank Andrew for your helping in educating me.

cheers Bill

 

[j&lgray]

Bill,
Regarding your question #2, on the Laurie Ann, we have substituted the two flooded, 12 volt group 27 batteries with 4 flooded, 6 volt batteries and are pleased with the results.

 

[Stella Karuna]

Hi John:

I appreciate you help in recommending the 6V golf cart batteries as they have great storage capacity at a reasonable price. However my understanding - perhaps misunderstanding - from Andrews is that this is not a good idea. That is why I was trying to find a way to mix batteries with different internal constructions. I thought the duo charger from Balmer might do the trick, but it doesn't sound like it will work.

I am new to this battery technology thing. Sorry if I am a little bit slow. Is the rest of the boat this complicated? I was wanting to add a water maker and electric toilet. With the steepness of the learning curve, I will be earning a PHD in no time.

cheers Bill

 

[Andrew Custis]

Thanks to "Thataway" he has corrected me on some of the numbers I had given on the automatic charging relays. Here is the spec off of the website showing exact numbers. Thanks Bob!

•Protects sensitive electronics by temporary isolation of house loads from engine circuit during engine cranking
•Designed for 12 or 24 volt systems
•12/24 volt auto ranging voltage input
•Hermetically sealed contacts/vaporproof
•Waterproof rated IP67—temporary immersion for 30 minutes
•Ignition protected—safe for installation aboard gasoline powered boats
•Remote LED output indicates relay state away from ACR
•Supports high-output alternators up to 120 Amperes
•Dual sensing
SpecificationsIntermittent Rating: 5 min. 210 Amps
Continuous Rating 120 Amps
Nominal Voltage 12/24 Volts DC
Amperage Operating Current - continuous 15mA open
175mA combined
Terminal Stud Size 3/8"-16 (M10)
Terminal Stud Length 1.50" (38.1 mm)
Terminal Stud Torque 140 in-lb (15.5 Nm)
Cable Size to Meet Ratings 1/0 AWG
Terminal Ring Diameter Clearance 1.12" (28.4 mm)
Mounting #8 or M4
Relay Contact Position
Combine (30 sec.) 13.6V @ 12V DC
27.2V @ 24V DC
Combine (90 sec.) 13.0 V @ 12V DC
26.0V @ 24V DC
Open (10 sec.) 12.35V @ 12V DC
24.7V @ 24V DC
Open (30 sec.) 12.75V @ 12V DC
25.5V @ 24V DC
Open High 16.0V @ 12V DC
30V @ 24V DC

 

[Andrew Custis]

You will have to source the info on the 6 volt batteries. Since you are connecting them in series making them 12 volts, it might not be an issue. "Thataway" might have some better insight on this one.

 

[Levitation]

The thing you have to keep in mind Stella is that battery charging time with the engine is only a small fraction of the charging time spent on the AC power at the dock... So your system wants to be designed to maximize the control of the AC charging system... And as Andrew pointed out, the use of ACR combiners when running the engine works quite well for topping off all the batteries when underway...

Now, if you are going to spend months at a time swinging on the hook in the Caribbean or motoring up the Amazon River, then adding a 250 amp alternator and the Balmar equipment makes sense...

 

[Levitation]

Oh, and I am adding a bank of golf cart batteries in parallel with the 2 Group 27 12 volt house batteries... Other than having an isolation switch to separate the two battery banks (if necessary) I do not expect any problems keeping them charged...

 

[thataway]

On several of our long distance cruising boats we have used both Golf Carts (two in series to give 12 volts/ parallel to bring the amperage to what we needed for running the boat under sail on a couple of hours a day genset or engine run time). The potential issue is overcharging the engine start batteries. We would moniter the voltage in the engine start battery and take them off line if the voltage was sustained over 14.4 volts. We had two group 31 engine start and 6 golf cart 220 Trojan batteries. However, this was with a non electronic engine, so there was no draw once the engine battery was fully charged. This size of system would probably be overkill on any of the Rangers for house banks.

It is possible that you could drop the voltage to the engine start batteries with an isolator diode after it was charged, thus allowing adequate output to the engine battery, as more input into depleated house batteries were charged (a combination of a dual sensing ACR and diode for "maintance" running). This would drop the voltage by about .5 volts and keep the over charging from being a problem. The other question is: is the alternator ventillated properly to sustain the higher output with larger battery bank charging? Although the alternator is a high output (150 amps I believe), it is still a small frame, and needs lots of air flow for cooling. These types of alternations might void warantees, so be cautious.

Going to a larger alternator is an option--and if you do that you should consider a dual output alternator. But there are a number of considerations. These include: adequate air flow for the larger and hotter alternator, clearance around the engine in the engine room. and conversion to dual belt or a geared belt for alternator drive.

I have also heard of puttng a second alternator on this engine--but that is a bit more expensive with fabrication of new pullies and grackets. Plus all of the above issues.

 

[SlackwaterJack]

Gave my '05 R-21 a big hug today...she's got only two batteries, but not enough electrical demand to kill a single battery without a re-charge after a week of use. .

Starting to appreciate the simple life 😀

 

[Stella Karuna]

Thank you Levitation. Your point about matching your use of the boat with the electical system is very helpful. We will be recharging our batteries using the engine alternator as we spend lots of time on the hook rather than topping them off after we charge at the marina with AC shore power. When we are not boating we are sea kayakers and backcountry hikers who spend a couple a weeks at a time unsupported. We bought the Ranger in order to go to the west coast of Vancouver Island and explore the Great Bear Rainforest between Prince Rupert and Cambell River on Vancouver Island. The longer we can spend on the hook the better.

With that in mind, I appreciate the comments of thataway[/b] concerning long distance cruising. I share your concern about overcharging the start batteries if I put in a smart regulator like the Balmer. If I have a flooded house bank of approximately 400 AH, the alternator will be asked to supply 25% of the capacity or 100 Amp and if I have AGM batteries the alternator will be asked to supply 40% of the capacity or 160 Amp during the bulk phase. This assumes that the house and start and thruster batteries are all charged separtely. As thataway pointed out this may be a lot to ask of a small frame alternator. I was hoping that the Balmer Duo Charge would allow the battery bank to be charged separtely if I took out the ACR. thataway: Would this work as the isolating diode refered to in your post?

In the ideal I would like to put in a house bank with two Slim Line AGM SL 12/200 batteries connected in parallel to give me 400 AH. They are 12 volt batteries which are lighter in weight and smaller than the usual flooded golf cart batteries. (Reference West Marine catalog). As I understand it, the other advantage of AGM is that I can discharge to 80% while it is best not to go below 50% discharge with flooded. This means that I have 320 AH of usable juice with 2 x AGMs versus 220 AH with 4x 6V flooded Trojan 220. When one compares the dollar per available AH of two AGM mentioned above with four flooded golf carts, the price is about the same.

Andrew:
1. Could you comment on thataways's concerns about the alternator?
2. Can I add a smart regulator to the existing alternator which would ask for maximum power of 150 Amps from the alternator if I put in AGMs?
3. How can I modify this system so that I can keep the existing flooded starter and thruster batteries and add a 400 AH AGM house battery bank and charge them with a 3 stage regulator?

My objective is to have a system which I can use for extended cruising without recharging at the marina.

Thanks Bill

 

[Andrew Custis]

Thataway knows more about these alternators than I do. I have not outfitted any tugs with this kind of system.

 

[CaptMac]

On the subject of electrical questions - does it make any difference whether you leave shore power attached when you start the engine? I had never thought about it before, and can think of logical reasons why it may be correct, or incorrect. Does anyone know?

Thanks,
Mac

 

[j&lgray]

Bill,
One piece of corrected info: The 6 volts are 220 AH, when two are joined in parallel, that makes one 12 volt unit that is 220 AH. When there are 4 batteries, two sets of 12 volt at 220 AH, you have a 440 Amp Hour house bank. This is what we have on the Laurie Ann. We have been on the hook for 4 days and needed fresh water before we needed battery charging.

 

[Levitation]

Stella, I wonder if we are going at this "problem" from the wrong perspective... How about becoming more efficient instead of expensive alternators and custom installations...

Perhaps (and I am just thinking aloud here) you might be better served by:

1. Replacing all your lighting with LED lamps to vastly decrease the current you draw in the evenings... See my long - sorry about that - series of posts on this...

2. Adding a pair of house batteries in parallel with the 2 existing house batteries... I put mine over in the starboard locker for weight balance so I don't float listing to port...

3. Adding a pair of 130 watt solar panels to the sport rack to give you daytime charging while out kayaking - put them up on legs above the sport rack so you can carry a pair of kayaks underneath...
These are good folks who understand RV / Marine , etc. solar panel installation:
http://www.solar-electric.com/
And a local canvas shop that does boats will be able to build the supports for the panels...

4. Going to a super efficient AC/DC cooler chest to reduce current draw compared to the installed refrigerator.. Take a look here:
http://www.roadtrucker.com/engel/engel- ... reezer.htm

Then take a trip and see how it goes... Odds are that will be sufficient to keep the house bank from discharging so deeply that the engine boils the start battery...
If you still have overcharging of the start battery you have not wasted money as you have made your house system vastly more efficient and you can then dump money into the Balmer and/or HO-Alternator installation...

BTW, you can simply put a switch on the starter battery to take it off line when doing a heavy charge on the house batteries... From your postings I have the feeling you understand enough to manually control that battery from being over charged...
The alternative would be to put 2 or 3 heavy diodes in series (per Dr. Bob) and use a battery switch to place them in series with the start battery after you have been underway for 20 or 30 minutes (they can go in the negative lead, which is how I would do it)... This could even be done with a timer automatically...
And lastly, let us not forget the poor, lonely thruster battery that will also get boiled... For your style of cruising I would make the thruster battery just another part of the house bank...


I have the EU2000i Honda generator that I simply set out on the swim platform and it does an admirable job of powering the battery charger, etc. in the evening... More fuel efficient than running the engine...

And again, I intended to make a small suggestion and it turns into a polemic...

 

[Levitation]

Oh, and BTW I just woke up, your name is Bill, not Stella (oops)

 

[Stella Karuna]

Hello Levitation:

No problem, about the name. The boat's name is Stella Karuna and my name is Bill. Either is fine with me.

I love the details in your posts so don't cut back. Your post on LED replacement will save me so much research. Thank you for the freezer suggestion. We have been looking at the NovaKool, but the "road trucker" link has a freezer which is less power hungry. I also like your idea about the Honda 2KW generator.

I have been of two minds concerning the solar panel. They are a $1,200 option from Ranger and they give you one 135 Watt panel. I may get 10 Amp for 5 hours on the west coast, so this is pretty expensive Amp Hours. Would additional batteries and a better engine charging system give me cheaper AHrs?

In addition to yourself, John Gray and Thataway have suggested adding two house batteries and I am going to do that. I also think that Captain Mac added them. This is clearly the way to go.

It seems the devil is in the details. The engine charging system on the 25RC looks like it could be improved to increase battery life and more efficiently charge the batteries. The smart regulator is $300. Four golf cart batteries cost about $800. The ACR is inexpensive at $99, but charging batteries individually according to their needs should increase the life of all the batteries. I think in one of posts on "Thrusters", you have a link to "Multiple Output Battery Charges" from Blue Sea. I think this is a $400 fix. In there it says that there is no problem using the ACR if charging from the alternator (assuming you are not mixing AGM with Flooded batteries); however, they advised disabling the ACR when charging from shore power. Not sure I understood the reason, but I will take Blue Sea's word for it.

It seems to me that it is worth spending the money now to get the best possible engine charging system when I am putting in new house batteries. I read somewhere that batteries don't die. Users kill them.

Thanks again for all your comments. This is just awesome. I am learning so much.

Bill

 

[thataway]

Here is a link which discusses the Balmar Digital Duo Controler, Echo chargers and Sterling Power systems (just to confuse the issue)--but these are some good solutions when using different batteries--and this thread gives several sides of the coin.

The reason to use AGM batteries is if you want to put the batteries inside of the cabin, or on side or ends. Otherwise lead acid batteries are the best value. Golf carts give the most bang for buck and are true deep cycle.

With the single wire alternator output system and internal regulator, one of the above solutions would be best and least expensive. Be sure that you have a good digital amp and volt meter (reading both input into the house bank and output. I also moniter each of my batteries with a Blue Seas Digital volt meter). This way you can know exactly how much current is being put into the batteries. One of the link type of systems also gives amps hours remaining or used and is very useful.

The idea of the diode isolator is just an in-expensive solution--and would work--being similar to the Duo or Echo type of chargers above. But this takes some fiddling and manual switching. (Which I like to do).

You can put in a dual output alternator--or even rework the current alternator, and use a dual output external regulator (I don't know if the Yanmar is a "P" or "N" type of alternator--but it could be re-worked. I would not do that--just use one of the above systems.

 

[thataway]

Solar pannels and or wind generator; There are some boats which are running purely on these in a sunny and windy part of the world such as the Caribbean. Solar power is relitatively expensive for serious power generation, and in the PNW there is less sun--and you are better with tracking panels whch follow the sun--this is difficult on a boat. You can use a couple of pannels, and it will helps some.

Often the biggest draw is the refer--as Denny-o suggested. There are expensive ways around that (I happen to use the chest type of refer on my current boat), you can add more insullation, or go to a holding plate system with custom insullation. The holding plate compressor runs off the engine, 110 volts or 12 volts and only runs an hour or so a day. Eutetic plates keep the compartments at predetermined temperatures.

As to drawing down batteries over 50%--There is certainly some controversary about this. My personal opinion is that one should not draw down any battery more than 50%--you will shorten the life span, with one exception. That is the very heavy duty "traction batteries"--such as used in forklifts. The weight of a battery equates to the amount of lead--and the capacity is directly related to this weight. The AGM can be charged more rapidly--and thus generate more heat in the alternator--than a lead acid--which means that the cooling is more important when using AGM batteries.
There is some literature which suggests that comperable Lead acid batteries will last longer than AGM batteries. Also consider where you are going to place and how to place batteries which can weight up to 150 lbs.

Finally looking at quality products--consider MasterVolt--both in Batteries and chargers.

Production boats are built to a competative price point for the average user. Those who go beyond the norm often customize the charging and battery systems, but that would not be cost effective for the average boater.