split charging Sailing Today

eidiohir

eidiohir

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This months mag has a article on the best method of splitting the charge to the batteries and comes down on the Adverc as the best.Nothing wrong with that I suppose but there should be some mention of the others sterling merlin at al. also there are those who champion relays as the best way forward such as Tony Brooks and Smartbank.Is it right that such articles should be presented as straightforward information when they are not?
 
I also found the article in PBO about alternator charge controllers very misleading. They compared different products but did not compare like for like. i.e. You had the cheapest model from one supplier compared with a more expensive from another supplier. If you compared like for like for the same price you may have found very different results. Whilst I appreciate the gear is probably restricted to what is on loan for the test I do think the article could have made mention of equivalents!
 
It was rather a strange feature - it's called 'which split charging system is best' and is almost entirely a general discussion about the various ways of doing it, which was OK. Then goes on to discuss external charge regulators and curiously names only Adverc (which is not of course in itself a 'split charging system' anyway).
Makes me wonder if the article was sponsored by Adverc maybe.
I thought the artilcle in PBO was rubbish really. It didn't actually compare performance of the units, simply saying that they all work - well, of course they work. The prices were wrong too, and one might have thought that they would wonder why it is that the Merlin and the Driftgate units look identical!
 
Read that article in PBO and I didn't notice that the products were not of the same standard. Its a case of caviet emptor I suppose but it would be nice to have some independent adviser in the market place
 
I suspect part of the problem is you have people doing a comparison when the area is not really their subject field. The article itself is ipso facto not very informative. It pretends to offer the reader an informed view but is ultimately completlely worthless. It reminds me of the BBC and Tomorrows World. That used to be a great program but then the presenters changed, the show dumped down etc in attempt to appeal to a mass audience. Ultimately the show died as the viewer figures tumbled and the tradditional viewer turned over.
IMHO the magazine is making the same mistake as the BBC. The article is no longer authorative and informative and offers the reader no more than a sales leaflet would do.
It is typical of why people are disallushioned in buying boating magazines. There is no education of the reader.
 
This is an area that I've been investigating with no success as I wanted to get a regulator to get the most out of my new boat's small battery bank.

Since the boat iss at SIBS I got one of the designers from the Merlin stand to have a look at my setup. The first thing he said was that regulators do not always give the advantage that people think, specifically with new engines that have already got more advanced regulators built-in.

After looking at Hawana which has a brand new Volvo D1-20 and 115A alternator, he said it was a great setup and a alternator regulator would be wasting money. As standard it came with some kind of voltage switching relay that as I understand it, charges the engine battery and when that reaches a certain voltage switches over to charging the service battery bank.

I didn't really have enough time to digest and get him to explain all the details, so does anyone know why this is a great setup?
 
Richard,

I am going through the same learning curve as I have to run my engine for about 6-8 hours each day at anchor to charge the batteries.

It seems that some people swear by VSR (voltage switching relay), and others by smart regulators so, if you have got a VSR system, it sounds like you are up to date.

have a read of Grenvilles battery stuff in the MOA technical library. Grenville swears by VSR, but says the other types are fine.... Neil swears by smart regulators, but says VSR is fine.

Bloody complicated stuff.

I guess the fact that a guy, who had a chance to sell you something, said dont bother, tells a large part of the story aswell.
 
6-8 hours a day at anchor is a hell of a lot of engine running to charge batteries, sorry but it is, you must have some major fault there. Are your batteries stuffed and wont hold a charge?
How big an alternator do you have on your engine and does it have smart charging already?
8 hours running means you are only getting 16 hours out of your batteries, that's awful for a liveaboard, what are your loads?
How large is your battery bank?
Do you have any solar as well?
 
The VSR and the smart regulator solve different problems. The VSR makes sure that the engine battery is charged as a priority over the domestic but it doesn't solve how to get the most out of your alternator.
The alternator controller is all about how to get the most out of the alternator relative to the state of the batteries.
 
talulah is absolutley right they do totally different things,the best idea is a combination of both but the priority would be the smart reg imho . re your charging richard something does sound wrong about the lenght of time you are running the engine,but i understand you are overhauling your charging system over the winter.
one thing to try,instead of 8 hrs charge for 3x2hrs with a gap of at least 2 hrs in between you may find the batteries will charge better and you can get it down to less than that.
batteries are like sponges,they take a while to absorb the charge,if you just keep running the engine in simple terms most of the charge runs off the top
 
I think that it was the combination of VSR with a new alternator that meant it was not worth buying a separate smart regulator. Apparently Volvo have recently improved the standard alternator regulator such that it is in effect a smart regulator.

I understand this is why you will now invalidate warranties if you take apart the alternator on new engines.

This is all what I understand, not what I know, so if someone knows better I would love to hear.
 
[ QUOTE ]
6-8 hours a day at anchor is a hell of a lot of engine running to charge batteries, sorry but it is, you must have some major fault there. Are your batteries stuffed and wont hold a charge?
How big an alternator do you have on your engine and does it have smart charging already?
8 hours running means you are only getting 16 hours out of your batteries, that's awful for a liveaboard, what are your loads?
How large is your battery bank?
Do you have any solar as well?

[/ QUOTE ]

You're sorry..... Tell me something I dont know /forums/images/graemlins/frown.gif

see here:

http://www.moa.myzen.co.uk/discus/messages/5/6474.html?1190016205

and here

http://www.ybw.com/forums/showflat.php/Cat/0/Number/1573207/an/0/page/4#1573207

if you want some bedtime reading /forums/images/graemlins/laugh.gif

Alternator is 50A or 60A and puts out 13.6v, (at least 15 years old)

No smart charging. No solar or wind power. no generator, (it died!!).

Engine - 126Ah
Domestic 2 x 126Ah = 252Ah
Inverter/Bowthruster 200Ah (in the bow, a long cable run from the engine/charging area)

So far I have removed the sensing cable from the alternator B+2 terminal and extended it to the domestic battery bank +ve terminal - I'm not sure if this has improved things, but it has lost me my rev counter reading, (even if I put the sense wire back on the alternator).

I am also considering fitting a diode in the sensing wire, with a switch in parallel, to con the regulator into increasin the voltage by 0.6v to 14.2v which, by all accounts, would increase the charge rate.

One thing I have noticed is that if the batteries are discharged by about 60Ah, the alternator puts in about 20Ah until they are discharged by about 40Ah, (as per a Sterling monitor). At 40h discharged It has dropped to putting in around 10Ah and, by the time the monitor shows them discharged by 30Ah, the input is down to about 4Ah. So I am now tending to let the batteries discharge to around -70Ah, and charge them to about -40Ah, but remain concerned that the batteries rarely get fully charged, except when I do a day sail under motor at about 2000 revs.

Cant really do anything serious about this till I get to a winter berth in Malta, (mid/end October or so), but am researching the pants off it!

Any ideas welcomed, but they may be better placed in the Charging my Batteries thread for continuity.

Cheers

Richard
 
I was also impressed that he declined from selling their own regulator and it definitely gave an air of credibility which made me feel that the VSR option must be good.

I can only assume that the Volvo regulator does now provide the 3 stages to charging as standard.
 
[ QUOTE ]
I understand this is why you will now invalidate warranties if you take apart the alternator on new engines.

This is all what I understand, not what I know, so if someone knows better I would love to hear.

[/ QUOTE ]

Richard,

i would be tempted to see how it goes before spending any money on a smart regultor or whatever - given the ease with which you can access stuff, I dont think it would be a difficult thing to add.

Sterling do something which doesnt involve opening the alternator and soldering wires to bushes, so there is something available which doesnt invalidate warranties, (so they say).

I'm with you on undertsanding, but not knowing /forums/images/graemlins/confused.gif
 
The people at Merlin really promote the VSR thing, and (I sense) don't really like smart regulators - they only seemed to bring out their AMS unit reluctantly, presumably because people were asking for them. I have an AMS, and it works. VSRs and smart regulators are not an either/or thing.
Interesting that you're hearing that V-P have souped up their charging technology. Hefty alternator you have, too, 115A wow!
Looked at your boat the other day, very nice I thought but I flinched a bit at the price. I think you ought to get them to do something about the starboard keel, too, rough finish! Add it to the snagging list......
 
Well I posted there, anyway, I would, in order of preference, make sure the alternator belts are tight,
fit a smart regulator,
have the batteries checked proffesionally. (how old are they)
Fit a VSR for your engine domestic batteries,
fit a battery to battery charger in the bow for the bowthruster battery.
Get your genny fixed,
buy a couple of solar panels, and regulator (120 watt)
Fit a larger domestic battery bank, IMHO 252ah domestic for a liveaboard is too small,
Make sure you a have an excellent 50 amp mains three stage charger,
that's about it, in priority.
This would make quite a difference (comfort and stresswise) to your life as a liveaboard.
IMHO
 
Yes I was amazed at the size of the alternator on a little 20hp engine. It would also make sense that if they have put a whopping alternator on, that they may have worked on the regulator as well. I have got a battery monitor, so would be interested to know what I should expect to see if the standard regulator is doing a good job.


Agree on the keels. I thought about getting them faired, but decided that the performance impact is so small as to be not worth the effort. I had my keel on my old boat faired and I couldn't tell the difference myself.

Actually it would be interesting to hear your thoughts on whether what you saw is normal for an unfaired finish and whether I should complain about it to get it dealt with??
 
Not sure that is solves everything!

Some points.

The new emmission relulations on engines preclude you from altering ANYTHING - even the alternator. This may be a reason for warranty problems.

Whilst a switch/relay is effective, and does not loose voltage in the tranmission accross it, and is a great improvement on the old splitting diode method, you will be getting the modern alternators full output of 14.2 volts probably - and that means all the time, as I do not believe that they have provided a multiple stage charging yet. Now for the weekend yachtsman this is not usually a problem, however if you are motoring for 24 hours and the charge continues at 14.2, then you will overdo your batteries. They need to be able to pull back to a float charge of 13.3 or so.

This was where the diode was useful, in that it naturally pulled the float charge down, but would provide you with a crappy charging system, unless you added a regulator "booster" such as Stirling or Adverc to bring the charge back up again to around 14.4 to 14.8. So even 14.2 will not really charge your batteries properly.

You can do some simple tests yourself if you have an ACCURATE voltmeter, checking what happens at various stages of charge.
 
[ QUOTE ]
.....Agree on the keels. .....Actually it would be interesting to hear your thoughts on whether what you saw is normal for an unfaired finish and whether I should complain about it to get it dealt with??

[/ QUOTE ]
If it was my boat I'd ask them to do it.
 
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