Alternators Again !!

[Billypownall]

Well they are important. Following my ealier posting about poor voltage at the batteries from a Barrus Shire 110 amp Alternator. Hopefully after much welcome advice all round the matter of a .5 volt drop from the our alternator to the batteies is going to be resolved by a larger sized cable . However one matter has been raised which really concerns me. Barrus say their 110 amp Alternators are not covered by a guarantee if they are charging a battery bank larger than 330 amps. Surely most battery banks are larger than this. Furthermore as I see it if you take 100 amps from a 300 amp battery bank it is the same as taking 100 amp from a 600 amp battery bank and you have to replace the same amouint. Am I missing something ? The Barrus engineer says my alternator is working too hard to charge a 660 battery set. Is this true? How many other manufacturers impose a limitation on battery bank size ? Peter Taylor at Barrus by the way deserves praise for his attention to moaning customers like me. However as he knows all I want to see is over 14 volts at my batteries.

[Gibbo]

Well they are important. Following my ealier posting about poor voltage at the batteries from a Barrus Shire 110 amp Alternator. Hopefully after much welcome advice all round the matter of a .5 volt drop from the our alternator to the batteies is going to be resolved by a larger sized cable . However one matter has been raised which really concerns me. Barrus say their 110 amp Alternators are not covered by a guarantee if they are charging a battery bank larger than 330 amps.

 

I wonder if that is written in their guarantee?

 

Sounds like a complete crock of sh*t to me.

 

Talk about looking for a "get out"

 

Surely most battery banks are larger than this.

 

Indeed. And Barrus *must* know this. If their alternators aren't man enough to charge a typical battery bank used with one of their typical engines that they *knowingly* sell to boat builders then the argument of "not fit for purpose" arises in my eyes.

 

Furthermore as I see it if you take 100 amps from a 300 amp battery bank it is the same as taking 100 amp from a 600 amp battery bank and you have to replace the same amouint. Am I missing something ?

 

Well taking it out is the same. Putting it back in is a different matter. A bigger battery bank is capable of drawing a higher charge current. But an alternator is current limited anyway, the fact that the batteries are capable of taking more is irrelevant. The alternator simply won't produce more than it is capable of. Unless, of course, it's a rubbish alternator.

 

The Barrus engineer says my alternator is working too hard to charge a 660 battery set. Is this true?

 

That's a bit vague really. It's a bit small admittedly. That just means it will take longer to charge the batteries. As for damaging the alternators it is complete cr*p. Unless, as I said above, it is a rubbish alternator.

 

How many other manufacturers impose a limitation on battery bank size ?

 

I've never heard of it.

 

Gibbo

[Justme]

Chargers are often specked in the same way by the sellers / makers.

I always thought that too was a crock of sh1t.

 

 

Justme

[Guest]

If that is true of a typical alternator, then we are all stuffed. Never heard the likes of it personally.

[Billypownall]

I wonder if that is written in their guarantee?

 

Sounds like a complete crock of sh*t to me.

 

Talk about looking for a "get out"

 

 

Thx for your reply Gibbo. I will be an expert on alternators soon although I would be pleased if I never saw one again. Item 16 in the Barrus Shire hadbook states:- " Domestic Batteries that are too large greate excessive loads on the domestic alternator. Alternators running at maximum output will eventually fail. Alternators that fail due to the battery bank being over the maximum size (which they later give) will not be covered by warrentee"

[Gibbo]

Item 16 in the Barrus Shire hadbook states:- " Domestic Batteries that are too large greate excessive loads on the domestic alternator.

 

This is bullsh*t. Properly designed alternators will run at full output indefinitely (until something weasrs out). They limit the current themselves.

 

Alternators running at maximum output will eventually fail.

 

I could make statements that are just as true, and equally as silly. Here are a few............

 

Alternators which are used will eventually fail.

 

Cars that are driven will eventually fail.

 

People that breath will eventually fail.

 

See my point?

 

Alternators that fail due to the battery bank being over the maximum size (which they later give) will not be covered by warrentee"

 

I suspect Trading Standards might take a different viewpoint.

 

I suppose it could be argued that any company is allowed to limit what one can and cannot do with their product in order to keep the warranty valid. But if that's the case here then they should have a rider saying something like ".... because our alternators aren't as good as the competition who have no such restriction".

 

Gibbo

[Guest]

Interesting one this IMHO. This is one case where it might be worth splitting the battery bank and using one of those two way switches. That way you would only be coupled to a battery bank of the given rate at any one moment. Once one bank is charged you then switch over to another suitably sized battery bank. That way you are complying with the rules. Could they argue with that one?

As an aside, what would their reaction be if anyone fitted a Sterling or similar battery boiler to their alternator? These supposedly make the alt. work harder and could they dishonour the warranty in a similar way to having "too large a battery bank"? Just a thought.

[Gibbo]

Interesting one this IMHO. This is one case where it might be worth splitting the battery bank and using one of those two way switches. That way you would only be coupled to a battery bank of the given rate at any one moment. Once one bank is charged you then switch over to another suitably sized battery bank. That way you are complying with the rules. Could they argue with that one?

 

Going from that silly restriction in the warranty I would guess they'd try to say someone had left the switch in the "both" position.

 

It's the sort of "squirm out" I only expect to see from insurance companies not boat engine suppliers.

 

Plus it would *almost* double the recharge time.

 

As an aside, what would their reaction be if anyone fitted a Sterling or similar battery boiler to their alternator? These supposedly make the alt. work harder and could they dishonour the warranty in a similar way to having "too large a battery bank"? Just a thought.

 

I've come across loads of engine suppliers dishonouring alternator warranties as a result of external alternator controllers.

 

Gibbo

[Nickhlx]

Going from that silly restriction in the warranty I would guess they'd try to say someone had left the switch in the "both" position.

 

It's the sort of "squirm out" I only expect to see from insurance companies not boat engine suppliers.

 

Plus it would *almost* double the recharge time.

 

 

 

I've come across loads of engine suppliers dishonouring alternator warranties as a result of external alternator controllers.

 

Gibbo

 

 

I was speaking only this afternoon to Beta about a 43 I am intending to spec for ours and they now fit a 175 amp domestic charge alternator ( and a 45 amp engine start alternator) and they do say that fiting an external charge controller will invalidate the warranty.. however the output voltage is fixed at 14.60 apparently ( not adjustable) and say it is good for any sort of battery chemistry, wet or AGM.

 

To me its sounds like certain sources of information are surfing the boundaries / limits of their expertise, although to be fair, 14.6 is probably a good compromise - Beta did sound to me to be offering very good advice on all the subjects I was asking them to confirm or for advice on.

 

Nick

[Guest]

Just as I suspected really then, if one fits a battery boiler the (alternator) warranty may well be stuffed.

[Nickhlx]

Just as I suspected really then, if one fits a battery boiler the (alternator) warranty may well be stuffed.

 

 

Well, that doesn't stack up with Gibbo's comment ( and others ) that alternators are inherently current limiting...

 

and if you install an alternator controller with temp sensor for the alternator ( and the batteries ) I would have thought it would be fine. The alternator will be working flat out potentially for way longer than needed to overheat and self destruct if it was presented with 800 aH of batteries to charge from dead flat... ( wouldn't it ? )

 

Nick

[smileypete]

Interesting one this IMHO. This is one case where it might be worth splitting the battery bank and using one of those two way switches. That way you would only be coupled to a battery bank of the given rate at any one moment. Once one bank is charged you then switch over to another suitably sized battery bank. That way you are complying with the rules. Could they argue with that one?

 

If the engine had 2 alts I'd consider splitting the bank and having each half bank charged by it's own alt.

 

If the alts have a similar output, charging with both 'half banks' (and therefore alts) connected together should only benefit by helping to average out the current from each alt.

 

cheers,

Pete.

Edited May 29, 2008 by smileypete

[Ex- Member]

I do remember someone saying that splitting your battery banks is less efficient. I recently mentioned I was adding another battery bank of 3 x 110amp each, i was going to use these three as a back up battery bank to the bank of 6 we already have, it was either chris w or possibly gibbo that suggested that a single bank of nine batteries was preferable to 2 separate banks. Can't remember the reason why though I do have 2 alternators one for battery bank one for engine battery, but will be linking them.

[smileypete]

I do remember someone saying that splitting your battery banks is less efficient. I recently mentioned I was adding another battery bank of 3 x 110amp each, i was going to use these three as a back up battery bank to the bank of 6 we already have, it was either chris w or possibly gibbo that suggested that a single bank of nine batteries was preferable to 2 separate banks. Can't remember the reason why though

 

True, having a single big bank instead of 2 half size ones will get you 15-25% more efficiency when discharging the batteries.

 

Though with a huge bank that gets lightly used, splitting it into 2 can open up some wierd and wonderful possibilities...

 

cheers,

Pete.

[Gibbo]

Well, that doesn't stack up with Gibbo's comment ( and others ) that alternators are inherently current limiting...

 

Well it does.

 

and if you install an alternator controller with temp sensor for the alternator ( and the batteries ) I would have thought it would be fine.

 

It will be fine. But they still like to have a "get out". I think this "external controllers void the warranty" started when the only commonly available ones were the Kestrel and the Adverc, neither of which have alternator temperature sensing. With a temp sensor on the alternator there is no valid reason for it. Apart from inexpert attempts (butchery) at modding the reg can destroy it.

 

The alternator will be working flat out potentially for way longer than needed to overheat and self destruct if it was presented with 800 aH of batteries to charge from dead flat... ( wouldn't it ? )

 

The internal reg has temperature sensing to prevent damage to the alternator (not to detect ambient temperature for charge voltage adjustment as someone else seems to think). If an external reg overrides this then damage to the alternator can result. If the external reg measures the alternator temperature and reduces the charge current accordingly then there is no problem. It is irrelevant how big the battery bank is.

 

Gibbo

[Nickhlx]

Well it does.

 

 

Yes - I was agreeing with you... What you had said was "Properly designed alternators will run at full output indefinitely (until something weasrs out). They limit the current themselves "

 

and what I was trying to say, was that AS alternators ARE inherently current self-limiting, the claim that

 

" the charge controller with alternator temp sensing will cause its early failure"

 

can surely not be the case ?

 

I think I have tried to express it more accurately this time

 

Nick

[Gibbo]

I think I have tried to express it more accurately this time

 

You have indeed. If there is no alternator temp sensing then there is a chance the alternator will burn out. If there IS alternator temp sensing and the alternator burns out then it would have done so anyway. With or without the external controller.

 

I'll put this in plain Ingerlish for the benefit (detriment?) of a certain engine supplier.

 

If an alternator burns out because it is charging a big battery bank then the alternator is sh*t and not fit for its intended purpose.

 

I believe Trading standards would have a field day.

 

Gibbo

 

PS I do happen to know from my own experience that Barrus have had alternator problems for at least the last 5 years. It seems they still haven't been solved.

Edited May 29, 2008 by Gibbo

[Nickhlx]

You have indeed. If there is no alternator temp sensing then there is a chance the alternator will burn out. If there IS alternator temp sensing and the alternator burns out then it would have done so anyway. With or without the external controller.

 

I'll put this in plain Ingerlish for the benefit (detriment?) of a certain engine supplier.

 

If an alternator burns out because it is charging a big battery bank then the alternator is sh*t and not fit for its intended purpose.

 

I believe Trading standards would have a field day.

 

Gibbo

 

PS I do happen to know from my own experience that Barrus have had alternator problems for at least the last 5 years. It seems they still haven't been solved.

 

 

Thanks..

 

If nothing else, it has confirmed which engine I will not be going with..

 

Nick

[bargeeboy]

Well they are important. Following my ealier posting about poor voltage at the batteries from a Barrus Shire 110 amp Alternator. Hopefully after much welcome advice all round the matter of a .5 volt drop from the our alternator to the batteies is going to be resolved by a larger sized cable . However one matter has been raised which really concerns me. Barrus say their 110 amp Alternators are not covered by a guarantee if they are charging a battery bank larger than 330 amps. Surely most battery banks are larger than this. Furthermore as I see it if you take 100 amps from a 300 amp battery bank it is the same as taking 100 amp from a 600 amp battery bank and you have to replace the same amouint. Am I missing something ? The Barrus engineer says my alternator is working too hard to charge a 660 battery set. Is this true? How many other manufacturers impose a limitation on battery bank size ? Peter Taylor at Barrus by the way deserves praise for his attention to moaning customers like me. However as he knows all I want to see is over 14 volts at my batteries.

 

Your 50 amp batter charger was turned on yesterday and this morning the panel said 14.4. I turned the charger off and it said 13.8.

 

Boat now going from dock to the yard where we shall check again

[Sir Nibble]

A couple of years ago, Lucas sent out leaflets reminding garages to charge the vehicle battery from a mains charger when replacing a faulty alternator. It seems they had a spate of failures due to mechanics neglacting to do this and leaving the engine running instead, apparently they were finding that high output was available at speeds where cooling was still borderline and units were failing due to overheating. That may explain why they are attempting to soften the alternator's duty cycle by specifying a maximum size battery bank. Sounds like the chap who specified the component got it wrong.

On the subject of warrantees on "battery boiler" equipped alternators. I will not warranty an alternator modified for such devices, the reason being that I have no knowledge of nor control over the circumstances under which it is used. For all I can tell the boater will simply earth the field lead, the regulator could be faulty, or wrongly fitted. Of the thousands of alternators I have seen with this modification, I have never seen one with temperature sensing fitted!

[Billypownall]

Your 50 amp batter charger was turned on yesterday and this morning the panel said 14.4. I turned the charger off and it said 13.8.

 

Boat now going from dock to the yard where we shall check again

Thx Malcolm all I want to see is minimum 14.15 at the batteries from the alternator. No problem with the 50 amp battery charger. If the alternator is pushing out 14.21 (according to Barrus) at the moment it is disappearing before it gets to the batteries.

[Gibbo]

Of the thousands of alternators I have seen with this modification, I have never seen one with temperature sensing fitted!

 

I've put 3 stage charger battery temperature sensors in the fridge to increase the charge voltage

 

Gibbo

[Nickhlx]

I've put 3 stage charger battery temperature sensors in the fridge to increase the charge voltage

 

Gibbo

 

 

 

Good idea !

 

Nick