Power generation

[bottle]

There's also a 'battery energy' meter, but either it's bust, or not connected!

 

 

or the batteries are knackered and cannot hold a charge, or they are old and their capacity is reduced.

 

[i know you had them tested]

 

Running the engine for six hours (hgher than tickover) should get the batteries fairly well charged but probably not fully charged.

[Grace and Favour]

I think a more powerful alternator is needed.

 

Engine runs about 6 hours per day, now we've started cruising, I want that to be enough! It's annoying that winter both cuts cruising time for production AND increases lighting needs for consumption.

 

Consumption-wise we use a laptop about 3 hours, the water pumps (on demand) and some 12V lighting 6-7 hours this time of year (but I do like enough light to see - at home we've moved to low energy, but that still means at least one 30W in most rooms (was 200W incandescent)). No TV, microwave, toaster, etc.

 

Thanks for the suggestions about metering - at the moment there's a Vmeter but no Ameter. There's also a 'battery energy' meter, but either it's bust, or not connected!

 

Thanks again,

 

Roger

If you've not got them already - - I would strongly suggest LED's in your light fittings - they only use about 10% of the power of Halogen/incandescant (I think)

[George94]

Yes I have had this problem too with the same genset. Switch your inverter charge side to Weak AC to reduce the effect, or do as I did isolate ALL the 240v system when running the genny to charge. If you want to pm me I can tell you more about this but not in a public arena. I have now done away with the 230v alternator and have this weekend started using my reworked 12v genset. This is the blog link so far. Sorry can't do a Linky on the I pad http://dcgenset.blogspot.co.uk

 

I think 12v generation is a better way to go. It is after all what the engine does so well.

 

ETA it's the genset causing the problem NOT the Victron. Nor will the Victron clean up the poor sign wave which is the core of the problem.

 

I like your approach, but are you confident that the alternator will look after your batteries in the way a good multi-stage charger will?

[Biggles]

 

I like your approach, but are you confident that the alternator will look after your batteries in the way a good multi-stage charger will?

 

Totally. It's an alternator with a regulator all be it a big one. A smart charger only emulates what an alternator regulator does.

[Robbo]

I think a more powerful alternator is needed.

 

How many batteries (in Ah's) do you have, and what size is your alternator, without this information we can't tell you if your alternator is indeed powerful enough.

[Theo]

 

How many batteries (in Ah's) do you have, and what size is your alternator, without this information we can't tell you if your alternator is indeed powerful enough.

I think that the relevance of battery bank size to alternator size is often overstated. The important factors in deciding the size of the alternator needed are the daily consumption of electrical energy and the number of hours that the engine is running.

 

Gibbo uses the analogy of keeping the bath full. The size of the bath (battery bank capacity) is not important. The important factors are how fast the water runs down the plughole compared with how fast the taps can replace the water. If you don't generate enough to replace consumption then the biggest battery bank will go flat. The capacity of the bank just says how long that will take.

 

Nick

[Robbo]

I think that the relevance of battery bank size to alternator size is often overstated. The important factors in deciding the size of the alternator needed are the daily consumption of electrical energy and the number of hours that the engine is running.

 

Gibbo uses the analogy of keeping the bath full. The size of the bath (battery bank capacity) is not important. The important factors are how fast the water runs down the plughole compared with how fast the taps can replace the water. If you don't generate enough to replace consumption then the biggest battery bank will go flat. The capacity of the bank just says how long that will take.

 

Nick

 

Agree mostly, but if the OP only has 2 110ah batteries then the bank isn't big enough for his daily (or more like between charges) needs and may well be charging them up fully anyhow.

[Phil Ambrose]

 

Agree mostly, but if the OP only has 2 110ah batteries then the bank isn't big enough for his daily (or more like between charges) needs and may well be charging them up fully anyhow.

Agreed, that is why I and others askedthe size of the bank. I have known people moan about running out of power who, it transpired, only had a single 110a/h battery.

 

Phil

[Robbo]

Agreed, that is why I and others askedthe size of the bank. I have known people moan about running out of power who, it transpired, only had a single 110a/h battery.

 

Phil

 

Seen the posts as well, but still no answer from the OP regarding, so I thought I would put my 2p's worth in, that without this information any advice is meaningless.

[matty40s]

4 x 110ah domestic bank with a 65a alternator.

[Theo]

4 x 110ah domestic bank with a 65a alternator.

 

 

 

Agree mostly, but if the OP only has 2 110ah batteries then the bank isn't big enough for his daily (or more like between charges) needs and may well be charging them up fully anyhow.

 

 

Agreed, that is why I and others askedthe size of the bank. I have known people moan about running out of power who, it transpired, only had a single 110a/h battery.

 

Phil

 

 

 

Seen the posts as well, but still no answer from the OP regarding, so I thought I would put my 2p's worth in, that without this information any advice is meaningless.

 

I would agree with all this. I had not read far enough back in the discussion.

 

N

[mudslide]

Yes I have had this problem too with the same genset. Switch your inverter charge side to Weak AC to reduce the effect, or do as I did isolate ALL the 240v system when running the genny to charge. If you want to pm me I can tell you more about this but not in a public arena. I have now done away with the 230v alternator and have this weekend started using my reworked 12v genset. This is the blog link so far. Sorry can't do a Linky on the I pad http://dcgenset.blogspot.co.uk

 

I think 12v generation is a better way to go. It is after all what the engine does so well.

 

ETA it's the genset causing the problem NOT the Victron. Nor will the Victron clean up the poor sign wave which is the core of the problem.

Thanks for the confirmation . I suspected the genset was at fault and have isolated any sensitive 240v appliances . I only now run these from the inverter or the landline .

So the message is 'beware before spending a fortune on a large genset' ,

I don't need 6kva just to charge the batteries , I was hoping to have the genset kick in to relieve the inverter load or when the batteries reached a low voltage . All this is possible with the Victon but not practical if the genset fries the appliances.

I have yet to try 'surge protection' as suggested , I will get round to it when I can afford to risk another induction hob .

I like your modification to the Vetus , I'll study it a bit more and get back to you with some questions .

Edited November 24, 2013 by mudslide

[Biggles]

I really wouldn't bother wasting money on suppression. The problem is with the AVR not being very good. I replaced mine with a 6 wire system from the original manufacturers (long story) which worked far far better and quicker at stabilising the voltage but of course still did nothing for the wave form.

 

If the voltage is too high theree is an adjustment on the original AVR. I turned mine down on initial trials to 215v no load and this seemed to cap the voltage to a max of 250v. The new AVR was pretty much spot on at 230v whatever the load was.

[DaveGood]

Good morning,

 

 

Not read all the way through this thread but seen a reference that it's not that important how big your alternator is compared to your Battery size. True in one sense but not in another.

 

If your alternator is say 50 amps trying to charge up say a 500 Ah battery pack that gets heavy use, your alternator will have to run full bore non-stop and will burn out real quick.

 

Barrus Shire, for instance, garuntees the alternators supplied with thier engines, unless you're trying to recharge a battery pack that's oversized for it. They say any alternator recharging a Leisure battery pack should be about one third to one quarter the size of the battery pack. So if you have a battery pack of say 500 Ah, your alternator should be somewhere around 150 amps. Otherwise, you'll burn out the alternator in pretty short order.

 

DaveGood

Edited January 19, 2014 by DaveGood

[Robbo]

Good morning,

 

 

Not read all the way through this thread but seen a reference that it's not that important how big your alternator is compared to your Battery size. True in one sense but not in another.

 

If your alternator is say 50 amps trying to charge up say a 500 Ah battery pack that gets heavy use, your alternator will have to run full bore non-stop and will burn out real quick.

 

Barrus Shire, for instance, garuntees the alternators supplied with thier engines, unless you're trying to recharge a battery pack that's oversized for it. They say any alternator recharging a Leisure battery pack should be about one third to one quarter the size of the battery pack. So if you have a battery pack of say 500 Ah, your alternator should be somewhere around 150 amps. Otherwise, you'll burn out the alternator in pretty short order.

 

DaveGood

 

 

Are in other words Barrus Shire (as well as other marine engineer manufactories) don't supply marine alternators, but automotive ones designed only for charging starter batteries.

[DaveGood]

Quite true Robbo,

 

however that still means anyone who does not have marine alernators on board (which is just about everyone reading this thread) should bear in mind that simply adding batteries to the Pack without beefing up the alternor that charges it will radically shorten the life of an expensive piece of kit (the alternator).

 

Match your alternator to the size of the Battery Pack, particularly if you are CCing. Or plaster a few pV panels on the roof.

 

Worth a mention I thought.

 

DaveGood

Edited January 19, 2014 by DaveGood

[George94]

Quite true Robbo,

 

however that still means anyone who does not have marine alernators on board (99.999 per cent of people following this thread) should bear in mind that simply adding batteries to the Pack without beefing up the alternor that charges it will shorten the life of an expensive piece of kit (the alternator).

 

Match your alternator to the size of the Battery Pack if you are CCing. Or plaster a few pV panels on the roof.

 

Worth a mention I thought.

 

DaveGood

 

Putting PV panels on the roof is not going to help in winter, which is when you most need power. However, I fully agree with matching alternator to bank (and to consumption).

[Ex- Member]

 

Putting PV panels on the roof is not going to help in winter, which is when you most need power. However, I fully agree with matching alternator to bank (and to consumption).

 

Our Panels brought in 165 amps today, pretty useful I would say as it's winter.

[George94]

 

Our Panels brought in 165 amps today, pretty useful I would say as it's winter.

 

I agree! But I am sure you will agree that though there are some days when you get something useful, you'd need a heck of a lot more panels if you were going to rely on them as your only power source, which is what DaveGood seemed to be suggesting.

[Ex- Member]

 

I agree! But I am sure you will agree that though there are some days when you get something useful, you'd need a heck of a lot more panels if you were going to rely on them as your only power source, which is what DaveGood seemed to be suggesting.

 

The days you get nothing are very rare, but of course there are days that yield a very low input. I recent chart I made up from the Outback regarding solar input showed an average through Nov of 75 amps per day and Dec 38 amps per day. Jan is looking better than Nov so far too.

 

Dave wasn't talking about replacing panels for additional energy, he was suggesting a bigger alternator. His suggestion of using solar panels instead of uprating the alternator is completely viable.

[DaveGood]

I didn't make myself clear George, I should have said something like " If beefing up to a bigger batterybank either get a bigger alternator to match it or add some PV panels"

 

DaveGood

[George94]

 

The days you get nothing are very rare, but of course there are days that yield a very low input. I recent chart I made up from the Outback regarding solar input showed an average through Nov of 75 amps per day and Dec 38 amps per day. Jan is looking better than Nov so far too.

 

Dave wasn't talking about replacing panels for additional energy, he was suggesting a bigger alternator. His suggestion of using solar panels instead of uprating the alternator is completely viable.

 

I suspect we have had more sunny days this winter than we normally do. Certainly it's been much warmer, though I appreciate that warmth and sun are not necessarily the same.

I didn't make myself clear George, I should have said something like " If beefing up to a bigger batterybank either get a bigger alternator to match it or add some PV panels"

 

DaveGood

 

Sure. Point taken.

[Alan Saunders]

Good morning,

 

 

Not read all the way through this thread but seen a reference that it's not that important how big your alternator is compared to your Battery size. True in one sense but not in another.

 

If your alternator is say 50 amps trying to charge up say a 500 Ah battery pack that gets heavy use, your alternator will have to run full bore non-stop and will burn out real quick.

 

Barrus Shire, for instance, garuntees the alternators supplied with thier engines, unless you're trying to recharge a battery pack that's oversized for it. They say any alternator recharging a Leisure battery pack should be about one third to one quarter the size of the battery pack. So if you have a battery pack of say 500 Ah, your alternator should be somewhere around 150 amps. Otherwise, you'll burn out the alternator in pretty short order.

 

DaveGood

No, no, no! Your alternator will not 'burn out'! It is a current limited device. Given a supply of cool air (@<40C?) and its fan operating in the correct direction even the smallest or largest alternator will cope and not fail with any load.

 

The real problem is getting your alternator to supply its maximum current. Increase the engine revs, shorten the cable-run, increase the cable size, use remote sensing, or a higher output regulator or a battery controller that, effectively, provides remote sensing to compensate for inadequate cables.

 

A large alternator may reduce the time for a daily bulk charge but the smallest alternator (even a dynamo) will satisfy the need for a weekly 100%, 8hr charge.

 

Alan

[DaveGood]

Good morning Alan,

 

I agree the alternator is a current limited device and a good supply of cooling air is required. as I understand it, the longer an alternator runs at full output, the more it overheats and stresses itself damaging the electrics, the electronics and the bearings. Once an alternator has delivered the bulk charge, and begins delivering the lower current absorption charge, it starts to, in effect "free wheel" part of the time, cooling down and reducing the strain.

 

An adequately sized Alternator for the bank will reach that point within an hour or two but a seriously undersized one doesn't, it will keep straining away at full load for hour after hour.

 

Or so I've been told.

 

DaveGood

Edited January 20, 2014 by DaveGood

[Ex- Member]

Good morning Alan,

 

I agree the alternator is a current limited device and a good supply of cooling air is required. as I understand it, the longer an alternator runs at full output, the more it overheats and stresses itself damaging the electrics, the electronics and the bearings. Once an alternator has delivered the bulk charge, and begins delivering the lower current absorption charge, it starts to, in effect "free wheel" part of the time, cooling down and reducing the strain.

 

An adequately sized Alternator for the bank will reach that point within an hour or two but a seriously undersized one doesn't, it will keep straining away at full load for hour after hour.

 

Or so I've been told.

 

DaveGood

 

 

Hi Dave

 

We have an 80 ap alternator to charge our 696a battery bank. The engine pulley driving the Alt was increased in size so the Alt will produce it's 80 amps at a lowly engine speed on 900 RPM So in effect our Alt runs at max chat all the time the batteries are capable of accepting it.

 

Our Alt has been used like this for 3 years now and is still in excellent condition and still puts out 80a at idle. I don't believe at all that Alt's will burn out quickly as you describe. They might last a less amount of time due to being used more but that's much the same for any mechanical moving part.

 

The Alt aside though, anyone without regular access to shore power should seriously consider solar panels, unless they have money to burn of course