Alternator Regulators - Opinions ?

[Kettlewell]

Also, my experience after motoring on a crossing.... say 8-12 hours. That my battery bank was as full as it can get.. call it 99%. That doesnt jive with his "72 hours required to fully charge..." What's your experience with that?

I don't think there is any controversy there--that last 1-2% takes a long time of charging at low amps--which is where solar panels can be handy to supply that final finishing charge so you don't have to run the engine forever.

[cburger]

Originally Posted by Kettlewell

Yes. Those are internal regulators for 10SI and 12SI Delco alternators. I have switched around and tried various ones.

Someone else was asking about charging your starting battery at the same voltage as your deep-cycle house batteries. What I do is have all the alternator output go directly to the house bank of deep-cycle batteries with a Trik-L-Start that feeds charge to my starting batteries once the house batteries are getting a decent charge. The Trik-L-Start drops the voltage by 0.2 volts, which seems to work out well for the starting battery. I also feed all the solar panel power direct to the house batteries and the Trik-L-Start keeps the starter battery ready to go no matter what. Remember, there is no reason your starting battery should get a deep discharge--if you are discharging it a lot, something else is wrong with your engine. If it doesn't start right up, you should fix that problem first. Therefore, your starter battery never needs much of a charge.

I was wondering if just making my start battery a deep cycle type would be a solution to charging at 14.4 volts. My old Perkins doesn't seem to take a real lot of cranking amps to get her running? Also wondering if any of the CF members have any experience with the Smart Gauge components http://www.smartgauge.co.uk/controllers.html on their vessels?

[btrayfors]

Originally Posted by cburger

I was wondering if just making my start battery a deep cycle type would be a solution to charging at 14.4 volts. My old Perkins doesn't seem to take a real lot of cranking amps to get her running? Also wondering if any of the CF members have any experience with the Smart Gauge components SmartGauge Electronics - Are alternator controllers really necessary? on their vessels?

I wouldn't. And don't.

A real simple solution -- and a real good one -- is to use a proper starting battery for the engine, and a separate deep-cycle house battery bank. Then, just connect a voltage follower device like the Xantrex EchoCharge or the Balmar DuoCharge to keep the starter bank fully charged and happy.

BTW, you don't have to worry about higher charging voltages or plate damage: even if the house battery voltage goes above 14.4VDC, the EchoCharge limits the voltage going to the start battery to 14.4VDC.

Clean, simple, requires no switching or maintenance. Just does it's thing quietly -- and has a pretty flashing light :-) Mine has worked flawlessly since installation in June 2004, as have others I have installed on client's boats.

Bill

[FlyingCloud1937]

Just a word of warning on parasitic chargers.

They're not all created equal.

2 scenarios where an echo charger is the wrong choice.

1. The start battery is fully charged, and the house bank is deeply discharged. In this case the start battery will be held at 14.4 v until the house bank is full charged and moved into float. I have seen many a installation where the start bats, start pushing water from the overcharge, it causes positive grid plate corrosion, and shortens the life of the start bat.

2. The start bank is deeply discharged, and the house bank is mostly or fully charged. In this case the main charge source goes into float mode 13.2, before the start bank is fully charged. Remember the start bank needs to be held at 14.4 absorption until its fully charged. Now in this case a partially charged start bank held at a float voltage of 13.2, will sulfate. This will shorten the life of the bat due to sulfation.

I love and recommend parasitic chargers for the start bank, just not an echo charger. If you're going to use a PC make sure it's one that has it's own charging regime, and sense the battery that it's charging.

The follow the leader parasitic chargers, stay away from.

What make a smart charger isn't the three stage charging it's the voltage corrected temp controlled charging that makes it smart.

Lloyd

[btrayfors]

Sorry, Lloyd, but I just disagree with the outcomes cited in both of those scenarios.

In the first place, a voltage of 14.4VDC applied to a near fully charged start battery for a few hours isn't going to "push water", unless the battery itself is already compromised. In fact, it's a good thing to periodically apply "absorption" or "acceptance" level voltages to batteries which are "fully charged". Keeps the sulfation process at bay and, in time, improves their overall condition (as contrasted with just floating them at 13.2VDC which, in my experience and testing, just isn't enough).

The second scenario is highly unlikely to occur: why are you going to have a start battery which is deeply discharged, anyway? Engine starting takes a very tiny amount of AH (typically less than 0.5AH) from the start battery. That's replaced in just a few minutes after engine starting.

In the real world, on a cruising boat the first scenario is the norm: when you fire up the generator or the engine to charge the house batteries, the start battery is, typically, nearly fully charged anyway. So, voltage follower devices like the EchoCharge are likely to see a partially depleted house bank and a nearly fully charged start battery. This is the norm.

And, to my knowledge and in my experience over a number of years, there's no evidence whatsoever of damage to the start battery while charging the house batteries with a VF device.

If anyone has any real evidence to the contrary -- not theoretical musings -- I'd sure like to hear about it.

Bill

[FlyingCloud1937]

Originally Posted by btrayfors

Sorry, Lloyd, but I just disagree with the outcomes cited in both of those scenarios.

In the first place, a voltage of 14.4VDC applied to a near fully charged start battery for a few hours isn't going to "push water", unless the battery itself is already compromised. In fact, it's a good thing to periodically apply "absorption" or "acceptance" level voltages to batteries which are "fully charged". Keeps the sulfation process at bay and, in time, improves their overall condition (as contrasted with just floating them at 13.2VDC which, in my experience and testing, just isn't enough).

The second scenario is highly unlikely to occur: why are you going to have a start battery which is deeply discharged, anyway? Engine starting takes a very tiny amount of AH (typically less than 0.5AH) from the start battery. That's replaced in just a few minutes after engine starting.

In the real world, on a cruising boat the first scenario is the norm: when you fire up the generator or the engine to charge the house batteries, the start battery is, typically, nearly fully charged anyway. So, voltage follower devices like the EchoCharge are likely to see a partially depleted house bank and a nearly fully charged start battery. This is the norm.

And, to my knowledge and in my experience over a number of years, there's no evidence whatsoever of damage to the start battery from charging the house batteries with a VF device.

If anyone has any real evidence to the contrary -- not theoretical musings -- I'd sure like to hear about it.

Bill

Originally Posted by btrayfors;

If anyone has any real evidence to the contrary -- not theoretical musings -- I'd sure like to hear about it.
Bill

Bill

I have over thirty years installing and maintaining batteries.

That being said, I'm not simply musing.

If a bat being held for an indefinite time or longer then what needs to be to achieve absorption. It will shorten the life of the battery....period.

Why do all smart controllers, whether Invt/charge, Solar controllers, and stand alone charges, have a programed time of absorption, then to float?

Why do you think the old constavolt is affectionately known as the constant cooker. They're dinosaurs, and are mostly extinct.

Lloyd

[btrayfors]

Originally Posted by FlyingCloud1937

Bill

I have over thirty years installing and maintaining batteries.

That being said, I'm not simply musing.

If a bat being held for an indefinite time or longer then what needs to be to achieve absorption. It will shorten the life of the battery....period.

Why do all smart controllers, whether Invt/charge, Solar controllers, and stand alone charges, have a programed time of absorption, then to float?

Why do you think the old constavolt is affectionately known as the constant cooker. They're dinosaurs, and are mostly extinct.

Lloyd

Lloyd,

I'm certainly not meaning to impune your knowledge or experience.

But, I think you answered the point right there, if I understand what you're meaning to say. We're not talking about "an indefinite time or longer". On a cruising boat battery charging normally takes place over a fairly short time....one to three hours or so.

My point is simply that a flooded start battery subjected to 14.4VDC for a few hours isn't going to be harmed at all. Rather, it's likely to be helped to avoid stratification and sulfation (which DOES occur at the normal float voltage levels of 13.2-13.6VDC).

Bill

[Maine Sail]

Originally Posted by btrayfors

Sorry, Lloyd, but I just disagree with the outcomes cited in both of those scenarios.

In the first place, a voltage of 14.4VDC applied to a near fully charged start battery for a few hours isn't going to "push water", unless the battery itself is already compromised. In fact, it's a good thing to periodically apply "absorption" or "acceptance" level voltages to batteries which are "fully charged". Keeps the sulfation process at bay and, in time, improves their overall condition (as contrasted with just floating them at 13.2VDC which, in my experience and testing, just isn't enough).

The second scenario is highly unlikely to occur: why are you going to have a start battery which is deeply discharged, anyway? Engine starting takes a very tiny amount of AH (typically less than 0.5AH) from the start battery. That's replaced in just a few minutes after engine starting.

In the real world, on a cruising boat the first scenario is the norm: when you fire up the generator or the engine to charge the house batteries, the start battery is, typically, nearly fully charged anyway. So, voltage follower devices like the EchoCharge are likely to see a partially depleted house bank and a nearly fully charged start battery. This is the norm.

And, to my knowledge and in my experience over a number of years, there's no evidence whatsoever of damage to the start battery while charging the house batteries with a VF device.

If anyone has any real evidence to the contrary -- not theoretical musings -- I'd sure like to hear about it.

Bill

What Bill forgot to mention is that the Echo also has an inherent voltage drop across it. With a house bank seeing 14.4V I have yet to see an Echo pushing 14.4V out the other side. Usually around 14.2V..

I have yet to see the anything of the sort that Lloyd claims happens with the Echo. If anything the start batteries on the Echo installs I've done take little to no water, even after a couple of years. I have a battery on my bench right now that is a June 2007 and is still exceeding its new CCA rating and carbon piles at like new, it has been charged via an Echo since installed..

In theory it sounds like it could happen but with the inherent voltage drop and 14.4V limit it simply has not. I've probably installed 60-80 of them, if I had to guess, just did another one two weeks ago, and see the batts on a regular basis. Zero issues.

[FlyingCloud1937]

Originally Posted by btrayfors

Lloyd,

I'm certainly not meaning to impune your knowledge or experience.

But, I think you answered the point right there, if I understand what you're meaning to say. We're not talking about "an indefinite time or longer". On a cruising boat battery charging normally takes place over a fairly short time....one to three hours or so.

My point is simply that a flooded start battery subjected to 14.4VDC for a few hours isn't going to be harmed at all. Rather, it's likely to be helped to avoid sulfation (which DOES occur at the normal float voltage levels of 13.2-13.6VDC).

Bill

Bill,

I'm not taking anything personal. Just remember one thing, this a public forum, and many will misunderstand that one size fits all.

Most house banks are going to be much larger then the start bank. So if you take a fully charged start bank, and a 1/2 discharged house bank. Next lets just say it take 6-8 hrs to completely charge the house bank. That's going to be at least 4 hrs of overcharge to the start bank.

Now how many hrs of over charge is going to accrue to the start bank over 30 days of cycling the house bank, how many hrs over 12 months is going to accrue?

Now a word on combiners, which I don't like unless the bats are equal size and similarly discharged.

Take a 2 banks one larger then the other, one 1/2 discharged, and one fully charged, take a voltage reading, of each bank. Assume the house is 12.2, and the start is 12.7, now combine the 2, and take the voltage reading at each bank. What are they.

Lloyd

[colemj]

Here is some anecdotal evidence: We have two engines, each with a dedicated good quality 12v flooded automotive starting battery. We have a house bank of 6 T-105's. All charging sources (solar, alternators and 120V charger) go to the house batteries and the start batteries are recharged using combiners.

So, whenever the charging source(s) are above 13.1V, the combiners bring the starting batteries on line and keep them on line until the voltage drops below 13.1V.

We have the ability to push 32amps through the solar, 120 amps through the alternators and 200 amps through the 120V chargers off the generator. The voltage regulation is the same profile for all charging sources and the combined start/house battery banks often get 100amps in bulk for a good period of time before slowly ramping down to absorption levels, after which the solar keeps them at absorption/float levels.

We rarely get to float.

In our case, the start batteries are brought on line by the solar as soon as the sun comes up and are kept mostly around 14.3V until the sun goes down. The charging voltages range through the day between 13.5 and 14.8V. Every day for the past 13 years.

We are on our third set of house batteries. We have the original 13yr old start batteries, which still test good under a carbon pile load test.

True, this is a single case study, but we do not seem to have harmed our starting batteries by either using a combiner, nor by keeping them above 14V for 10hrs a day, every day for 13 years.

And yes, I know I am pushing my luck keeping them in service this long, but flooded starting batteries are easy to replace everywhere and I have the ability to parallel the engines to the house bank if the start bank fails.

Mark

[FlyingCloud1937]

Originally Posted by colemj

Here is some anecdotal evidence: We have two engines, each with a dedicated good quality 12v flooded automotive starting battery. We have a house bank of 6 T-105's. All charging sources (solar, alternators and 120V charger) go to the house batteries and the start batteries are recharged using combiners.

So, whenever the charging source(s) are above 13.1V, the combiners bring the starting batteries on line and keep them on line until the voltage drops below 13.1V.

We have the ability to push 32amps through the solar, 120 amps through the alternators and 200 amps through the 120V chargers off the generator. The voltage regulation is the same profile for all charging sources and the combined start/house battery banks often get 100amps in bulk for a good period of time before slowly ramping down to absorption levels, after which the solar keeps them at absorption/float levels.

We rarely get to float.

In our case, the start batteries are brought on line by the solar as soon as the sun comes up and are kept mostly around 14.3V until the sun goes down. The charging voltages range through the day between 13.5 and 14.8V. Every day for the past 13 years.

We are on our third set of house batteries. We have the original 13yr old start batteries, which still test good under a carbon pile load test.

True, this is a single case study, but we do not seem to have harmed our starting batteries by either using a combiner, nor by keeping them above 14V for 10hrs a day, every day for 13 years.

And yes, I know I am pushing my luck keeping them in service this long, but flooded starting batteries are easy to replace everywhere and I have the ability to parallel the engines to the house bank if the start bank fails.

Mark

We'll I'd like to believe in your anecdotal evidence....but I have worked in this industry way to long, and replaced way to many bats.

Now if you can provide me with any battery manufactures recommendation that chronically over charging is good for their bats, and may in fact extend their life. then maybe...

What I do see by review of your anecdotal evidence IIRR, you replaced your house bank 3 times in 13 years, and they are Trojan 105's being charged at 14.4

That works out to 4.3 years per bat bank....not very good in my mind. Trojans charge recommendation is 14.7 -14.8 temp compensated.

Lloyd

[colemj]

Originally Posted by FlyingCloud1937

We'll I'd like to believe in your anecdotal evidence....but I have worked in this industry way to long, and replaced way to many bats.

Now if you can provide me with any battery manufactures recommendation that chronically over charging is good for their bats, and may in fact extend their life. then maybe...

What I do see by review of your anecdotal evidence IIRR, you replaced your house bank 3 times in 13 years, and they are Trojan 105's being charged at 14.4

That works out to 4.3 years per bat bank....not very good in my mind. Trojans charge recommendation is 14.7 -14.8 temp compensated.

Lloyd

The recent third replacement of the bank is due to a lightning strike that shorted two of the batteries (and took out all of the electronics and a lot of the electrics). The whole bank was replaced as a precaution.

Ours is an actively cruised off-the-grid boat - 24/7/365, not a weekender or dock boat. 4-5 years out of T-105's in this environment is normal as per Trojan (actually, they say 3-4 years at our cycling regime).

The charging profiles on all controllers are set to 14.8V bulk/absorption, temp compensated. In a real cruising boat in the tropics with constant daily loads, 14.4 is a correct temp-compensated charging voltage.

Whether you believe my anecdote or not is inconsequential to it being true. My example is a real one, while you postulated hypothetical situations. If you have specific examples, it would be better to present them as cause and effect lessons rather than demanding that everyone take your word because you tell us you have more experience than we do. Particularly so given the qualifications and experience of many of the people you address who are responding to you in this thread.

I don't agree with you that they are being overcharged. As a test, I just turned on the charger and measured the current being supplied to the starter battery after being combined with the house bank for charging. The charger was putting 80 amps into the combined bank and the current going to the starter battery was a measly 0.9 amps. The voltage was 14.1 and climbing. So high current isn't an overcharging problem.

Keeping a battery above 14 volts for 10 out of 24 hrs is not an overcharging voltage problem either. Trojan recommends a constant float of 13.8V with an exercise voltage of 14.8 for a few hours every week or so to destratify the electrolyte. Most smart chargers have this profile built into them. All of ours do.

So our starting batteries see 13.1-14.4V at minuscule amperage for 40% of each day vs. Trojans actual recommendation of 13.8V for 100% of each day with a regular maintenance increase to 14.8V (although I must note that the starting batteries are not Trojans).

Your argument points on this topic appear to me to be rather theoretical and not taking into account real-life operation nor a typical cruising boat system and environment.

Mark

[cwyckham]

Originally Posted by Maine Sail

Funny, I wrote something along similar lines a while ago .. Never saw that one but it is good to know others understand this too...

Musings Regarding External Regulation

Thank you for an amazing article. I think that I actually concluded from it that I probably need an external regulator with alternator temperature sense. Can you check my thinking?

1. I have a 400 Ah AGM bank that I think is in good shape (need to do a test, planning on a drawdown type test as I don't have any fancy testers)

2. I have a 30 hp Westerbeke engine with the original 55A, 30 year old alternator on it.

I have been seeing really low charge rates on my link monitor (like 15 A) despite being down around 70% SOC. I now believe that this would be due to a low voltage set point on the very old internal regulator (untested at this point)

I believe a new alternator up around 100 A would be too much for my engine without modification, and my current (pun intended) thinking is to spend the money on solar panels and LED lights instead. I'd like to get as close as possible to not needing to run the engine just to charge.

I could just use a couple of diodes to fool the old internal regulator into delivering higher voltage, and this would do for at least the next few years before I head out and do some serious cruising where I might run the engine for 36 hours at a time on the very rare occasion and risk overcharging my AGMs.

However, your article suggests that I might cook my alternator if I don't use an external regulator with temperature sense as the likely acceptance rate of the battery bank is about 100 A in bulk, and if I get the voltage up to a decent level, the 55 A alternator may burn up. Did I get that right? These things aren't cheap, so I want to understand this before I go off half cocked.

thanks for your help

Chris

[cwyckham]

I managed to find the alternator description in the engine manual (It's a Mitsubishi 50 A). It indicates that the internal regulator is temperature compensated (for alternator temperature). If this is the case, I'm strongly considering doing this diode mod instead of spending $400 I don't have on a smart regulator and temperature sensor just to protect the alternator from overheating.

[btrayfors]

Originally Posted by cwyckham

I managed to find the alternator description in the engine manual (It's a Mitsubishi 50 A). It indicates that the internal regulator is temperature compensated (for alternator temperature). If this is the case, I'm strongly considering doing this diode mod instead of spending $400 I don't have on a smart regulator and temperature sensor just to protect the alternator from overheating.

Two thoughts on a quick read of this thread:

1. your 400AH AGM battery bank can easily accept 400A or more, not 100A; and

2. the diode mod looks like an easy solution, but given the huge charge acceptance characteristics of your battery bank and the small 50A alternator, you risk overheating it and burning it out.

There's no way around it: if you choose to go with AGM batteries then to take advantage of their charge acceptance capacity you need a very substantial charging capability.

And, if for whatever reason you're planning to stick with a low-output charging source, then you need to be sure you've taken steps to protect it from burning out (by doing something it was not designed to do, i.e., put out at near it's full rating over a sustained period of time).

And, you're going to have to put up with long periods of battery charging to get those AGMs up to full charge on a regular basis. Failure to do that will ensure the early demise of your AGM batteries.

BTW, your 30HP Westerbeke can probably handle a 100A alternator on a single belt, but it would be wise to have a smart external regulator which could be used to: (1) sense the alternator temperature; (2) derate the alternator output if desired; and (3) provide an easy way (like a simple switch) to cut the alternator output in half when/if you really need the HP.

Bill