New Balmar Alternator Charging Question

[a64pilot]

Originally Posted by SV THIRD DAY

You guys ever wondered how Cruiser dock rumors get started? I believe we just witnessed the birth of one.

? I don't understand?

Put another way, I'm wondering if 50% output is a good, average general rule. Meaning of course can you usually get 50% of an alternators output, or is it more of a set number and ratings mean very little. Meaning after they heat soak, you get the same from a 150 as you do a 200, if so then being a frugal guy, the lower priced 150 is a better buy.
Meaning is it more like 50% or is it more like 80 amps?


To begin with,how do people know their actual alternator output? I had to put a shunt and ammeter on my alternators output, otherwise I had no way of knowing, how do most tell output?
I don't think an ammeter for the alternator on a boat is common?

[a64pilot]

Originally Posted by mitiempo

They already do. Bosch does and they are on BMW's.

http://www.industrialbearings.com.au...1339475227.pdf

Maybe one day we will see something similar for boats.

[john61ct]

If you have room, a large-frame HD alt will output 100% rating no problem, but personally I would go bigger (350+A) and derate to 70-80% or even lower for greater longevity.

Reco Leece-Neville truck alts (for diesel) often go for well under $200, or get an old one have it reconditioned yourself. New $800+.

The mount retrofitting and conversion to serpentine is what'll cost you if you don't have the skills to DIY.

But again, if you don't use LFP, you're only cutting dino-juice runtime - which for many isn't important in the first place - by maybe 30-45 minutes.

Otherwise just no point striving for 100+A charging output **potential**.

This last issue may not be "what is being discussed" here, but I think is an important point to keep things in perspective.

[SV THIRD DAY]

Originally Posted by a64pilot

? I don't understand?

Put another way, I'm wondering if 50% output is a good, average general rule. Meaning of course can you usually get 50% of an alternators output, or is it more of a set number and ratings mean very little. Meaning after they heat soak, you get the same from a 150 as you do a 200, if so then being a frugal guy, the lower priced 150 is a better buy.
Meaning is it more like 50% or is it more like 80 amps?


To begin with,how do people know their actual alternator output? I had to put a shunt and ammeter on my alternators output, otherwise I had no way of knowing, how do most tell output?
I don't think an ammeter for the alternator on a boat is common?

Don't fixate on the 50% number that was just an example, driven more by your battery banks acceptance rate than the alternator.

I'm on a LOT of boats for installs and the vast majority do not even have a battery Amp Meter/Totalizer, let alone have the ability to really know what their alternator is putting out. One system that is constantly inadequate on most cruising boats is there electrical. We forget because here we are posting details on a chat room about electrical systems, BUT you would be surprised in the amount of cruisers I talk to that do not know the size of their battery bank in Amp hours or how much solar they have or a lot of details that all of us here, posting on these type of thread, would know and be able to report back seconds after being awoke at 3AM with a flashlight pointed in our face.

[a64pilot]

I don't mean to fixate on a percentage. It will vary of course due to ambient temp conditions in the engine room etc. a hot engine room is a difficult place to air cool anything.

Bank acceptance rate is why I believe most of these high amp alternators survive, cause the bank won't take what they can make most often.

My AGM bank will take 185 amps of my 120 VAC chargers for 20 min if it's at 50% SOC, less of course if higher SOC, and I have only let my bank get to 50% very rarely. I usually don't let it get below 80% or so.

I'm beginning to think that, maybe a high output small frame alternator is sort of a contradiction in terms, and maybe not worth the price of admission?

[deluxe68]

Originally Posted by a64pilot

I don't mean to fixate on a percentage. It will vary of course due to ambient temp conditions in the engine room etc. a hot engine room is a difficult place to air cool anything.

Bank acceptance rate is why I believe most of these high amp alternators survive, cause the bank won't take what they can make most often.

My AGM bank will take 185 amps of my 120 VAC chargers for 20 min if it's at 50% SOC, less of course if higher SOC, and I have only let my bank get to 50% very rarely. I usually don't let it get below 80% or so.

I'm beginning to think that, maybe a high output small frame alternator is sort of a contradiction in terms, and maybe not worth the price of admission?

The Balmar AT series comes in two sizes, 165 and 200. I assumed that they are probably identical except for the windings and that the 165 would be more able to dissipate its load. I will have to look at my alternator next time I am on the boat. From their web site:

"AT-Series Alternators also feature a dozen 50A capacity, externally mounted avalanche diodes, dual internal fans, and massive heat sinking designed to ensure essential cooling under high load demands."

[Exile]

Originally Posted by john61ct

If you have room, a large-frame HD alt will output 100% rating no problem, but personally I would go bigger (350+A) and derate to 70-80% or even lower for greater longevity.

Reco Leece-Neville truck alts (for diesel) often go for well under $200, or get an old one have it reconditioned yourself. New $800+.

The mount retrofitting and conversion to serpentine is what'll cost you if you don't have the skills to DIY.

But again, if you don't use LFP, you're only cutting dino-juice runtime - which for many isn't important in the first place - by maybe 30-45 minutes.

Otherwise just no point striving for 100+A charging output **potential**.

This last issue may not be "what is being discussed" here, but I think is an important point to keep things in perspective.

I think Maine Sail's number crunching examples in an earlier post above also demonstrate why keeping this perspective is important. Fwiw, my boat came to me with two internally regulated "dumb" engine alts., a 50A charging the 8D 255AH start battery (I know, overkill for a 80hp engine), and a second 50A charging the two 8D house batts (510AH) (I know, probably too small). Well, these alts. may not be so "dumb" since they put out 14.4V all the time, which Lifeline has told me is fine for bulk & absorption, and will likely do minimal harm on float. My engine room is also cramped & hot, something that even with my blower I'm not sure I could do much about.

So hardly a state-of-the-art engine charging system, but every time I consider upgrading to a larger, expensive alt. with ext. regulation & read these threads I start wondering why. Especially when I could simply take my two alts. down to a local alt. shop, have them checked out/rebuilt as necessary, and then purchase two more identical ones to have as spares. Given the minimal time saved during bulk charging, it doesn't seem worth the add'l cost. I should add, btw, that I have a genset that runs a 3-stage batt. charger when not motoring.

Am I missing something? Maybe I need to give Third Day a call??

[a64pilot]

I wouldn't want to run my Lifelines at 14.4V continuously, but of course that depends on how long your motoring.
You could of course watch charge rate and when it falls to .5% of bank turn the alternators off if your motoring for a long period.
Would make you have to pay attention of course.
I've often wanted a manual regulator, with a switch, one way absorption, the other float. Let me be in charge as opposed to the regulator.

[mitiempo]

Originally Posted by a64pilot

Maybe one day we will see something similar for boats.

They exist, have been around for a while. Remote diode pack is a good idea as well.

[john61ct]

A good SoC meter with a relay could turn field current on and off.

If I had a dedicated genset already being used regularly, I wouldn't spend money enhancing alt output.

[deluxe68]

Originally Posted by Stu Jackson

You're right. Which is exactly what Dockhead has been saying for the past year or more, right here.

Somebody earlier mentioned rocket science. He was right, this ain't it!

Same size case, and most likely bearings, but a bigger output means what? Is that your question, a64? I'm not an alternator-construction expert, for that you'd have to go to Maine Sail.

All I have been documenting and linking are my "use of the available." Take what products are out there, and use them as simply as possible, examining the OPTIONS of operation and management.

My conclusion was, uhm, simple for me: instead of using the cumbersome reed wand to re-program my alternator, and reduce its output throughout its range, I use SEM to reduce the load when the unit needs to do bulk charging, and then kick it back to 100% when the load is lower after bulk.

That's all.

A 165A alternator, WITH THE EXACT SAME LOAD, should, I say should, run cooler than a 100A alternator. In my links I explained how it appears that with my nominal 400ah house bank at 50% SOC, the acceptance of the batteries is between 50A and 70A. In other forums, Maine Sail has confirmed this. So, SEM kicks this load down to 25-35A, easily handled by my 100A alternator, which would not be happy with a continuous 70A load. When the load (output), as read on my Link 2000, goes down to 25A I kick the SEM off, and the alternator puts out 50A.

If I had a 165A alternator, I most likely wouldn't have to bother with SEM. Read the links you'll see why I do this.

Pretty simple, so am I.

But I have a 400 ah bank, as you do, and my 165 IS overheating during the short bulk mode where it is putting out 133 amps. I like the idea of the SEM derating the alternator 50%, I went thru the manual a few more times and it essentually shorts the alternator temp sensor. There is also an output on the regulator for an alarm light, might as well run two sets of wires while I am at it.

[Exile]

Originally Posted by a64pilot

I wouldn't want to run my Lifelines at 14.4V continuously, but of course that depends on how long your motoring.
You could of course watch charge rate and when it falls to .5% of bank turn the alternators off if your motoring for a long period.
Would make you have to pay attention of course.
I've often wanted a manual regulator, with a switch, one way absorption, the other float. Let me be in charge as opposed to the regulator.

That's what I thought too, but Lifeline said it's only a factor in much larger banks. Again, it may not be ideal but is it worth the cost & time to remedy? I've done several, 3-4 day runs down the ICW from Norfolk to Beaufort, NC with these batts. where I'm motoring all day, and it's now been 7 years on the same batts. In fairness, however, those 7 years have also (regrettably) entailed a disproportionate amount of time plugged into shore power, and periodic equalizing as well.

I think I understand the benefits of larger alts. & external regulation, but it may be a bit overstated. And then you have the problem of "smart" regulators going into float mode too early, something which arguably could do more harm than potentially "overcharging" at 14.4V.

[DeepFrz]

So, has anyone tried the fan/blower cooling the alternator to see if that works or not?

[Stu Jackson]

Originally Posted by a64pilot

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I'm beginning to think that, maybe a high output small frame alternator is sort of a contradiction in terms, and maybe not worth the price of admission?

Not necessarily. Let's take your situation. IIRC, you had to choose AGMs because of your battery bank layout. As a result, you have a bank that can accept a high rate of charge. You made the decision to get an alternator that could do that. That makes sense. It's a system.

I had a meager 55A alternator. It used to have an internal regulator, like many of my sisterships, actually most, not just many. My PO installed an AutoMac which got more out of the alternator - a manual external regulator, if you will. My choice, then, was to increase the size of my alternator and buy a Balmar MC-612. My limiting factor was the belt, so I stayed with a 100A alternator, and then "played" with the features of the MC-612 to both maximize the output and control it to avoid eating belts because I don't have the room for a serpentine belt system. It works at anchor for me, because I can put the SEM to full and run the engine at 1800 rpm and get twice as much out of my alternator than if I'd only had internal regulation. It's my system and it works for me.

Others have made the choice to keep their OEM alternators and install generators, regardless of the type. Others go directly to solar.

I used to sail more than I motored. I now motor a lot. Either way, I get twice as much out of my alternator than if I'd only had internal regulation. The controlling factor for me on alternator size was the belt. I don't have a generator or solar.

Point being: each of us have to deal with the space restraints and system and equipment availability and the way we use our boats to determine what the options are for what works for us.

I think you've done your homework quite well, based on what you write here on this forum. Rich is right that altogether too many don't know, but that's not what we're discussing here either (scary as it is).

I think it IS worth the price of admission to have done the research and homework to maximize the positive impact of the stuff we buy and install, and learn how to use it.

[john61ct]

If my alt was a significant charge source for my House bank, first change would be converting to Balmar MC-614.

Programmability of voltage setpoints and avoiding "premature infloatulation" is IMO a much higher priority than increasing amps output

And I know different batt chemistries are in my future, more likely near than far.