PaulG

Oh, my poor aching sides!

in my experience: female + washing machine + shower = empty water tank. It's on already, and I'm heading for the door....

I bet his engine warmed up quickly!

Thanks for that Gibbo. Yes, that's pretty much what I meant by derating. But I did qualify that by saying that "If you've got one of the modern, high output alternators, then it may well be cooled sufficiently to run at it's rated output for long periods." So wasn't really talking about specifying new installations, more about what it was reasonable to expect in performance from an existing unit, which may not be in its first flush of youth. From what you have said above, if you drive an alternator too hard for the cooling arrangement, either the output current falls as the temperature rises, which effectively "derates" it anyway, or, if there's no temperature sensing (was this feature always incorporated into older units? I don't know), it blows up. Either way, allowing a bit of "headroom" on the alternator seems to make perfect sense to me.

Heavens above no! I'd never even think of using such a terrible insult in a public forum! OK. Point taken. I hereby withdraw the use of the word "amply". Now you're just teasing me, aren't you? Well stop being so naughty.

Can't argue with that! I know, and so I respect his opinion. But see above. As I said before, I am sure that you are extremely knowledgeable. I wasn't taking the p*ss, I meant it. But, as you amply demonstrated, you can still be wrong! I didn't say you were. But if the cap.... Sorry. That was out of order. Puerile remark withdrawn unreservedly. Anyway, thanks for responding. Now, can you give me some advice on where I should mount my galvanic isolator? I'll get me coat..

Doh! NOW he tells me!

I agree with that. I had a leak in the same position, and I found that the collar never really got hot, even with a bit of a blaze going. I used a few drops of "Captain Tolley's" as it was only a hairline crack, and it's been fine ever since.

Sensible to get maximum publicity out of something that is probably an expensive exercise for B.W. "Pour encourager les autres"

Well I disagree. And, while I'm at it, I'd like to add some general comments. I've been jumped on for saying "Alternators are usually derated because they are badly cooled" and I accept that I did not word that statement very clearly. However, I did go on to explain what I meant: "Most alternators would get a bit toasty if run at much more than 70% of their rated output for any length of time. This is a generalisation, but it is sensible to de-rate them" I stand by that statement. They will run hot. Will they overheat? Possibly. In a closed engine bay, or having picked up dust and general crud over a few years of use. I also said that "If you've got one of the modern, high output alternators, then it may well be cooled sufficiently to run at it's rated output for long periods." I've tried to explain what I meant, and the reasons for it, so if you are going to disagree with me, then please do me the courtesy of explaining yourself properly as well. I have to say that the arrogant attitude of some of the contributors to this thread is a shame. Especially when some of the self-proclaimed experts seem have actually learned something from others. Finally, I should point out that I am a notoriously obstinate old bastard and I refuse to be browbeaten or otherwise bullied, so don't even bother trying!

Thanks for the explanation Robin. Luckily, at the moment, my consumption is parsimonious, battery bank puny, and battery type ok, and I've turned down both the charge current and the charge voltage, so it can probably last a couple of months longer.

Sadly, I've got other calls on my boating cash at the moment. But the K90 is gradually working its way up the list of replacement kit.

Hi Robin Conventional wisdom seems to suggest 14.8V as typical for a wet lead/acid battery. Can you explain this a bit more? Thanks

The webcam's very interesting technology, Gary. How do you achieve the 180 degree rotation of the image for your Australian clients? Is it done by IP address, time zone, or something similar?

You little tease! If only the wife hadn't confiscated my cheque book, I could be tempted. Especially as the "on the water" picture was taken in my home town of Tewkesbury. (Obviously during a drought!). I've even got a jigsaw puzzle of the same picture.....(sigh).

Hi Toad (Mr. Toad? Toady?) I'm pretty new here myself. I'm no expert on the bacon sarnie issue, so you're safe there! I'm very aware of Steve McIntyre. I've taken an interest in his work for many years. I'm not naive enough to think that he's right on every subject, but I think he did a bit more than "try" to discredit the Hockey Stick. He shot the whole thing down in flames, to the point where he showed that you could enter random data into the mathematical algorithms that the reconstruction used, and still get the distinctive "hockey stick" shape. Just playing devil's advocate here, does your peat core represent the whole world? Any sign of the Maunder Minimum or Little Ice Age in it? Any hint of Medieval Warm Period? I only ask because these phenomenae had mysteriously vanished from the Hockey Stick reconstruction. "..the IPCC report(s) were peer reviewed by practically the whole US government." What?? Lastly, are you trying to say that Steve M. in some way faked these documents? That they are somehow not genuine because they were posted by Steve M?

Hi Snibble. At the risk of reopening old wounds, the K90 installation instructions say "We advise you to never set a charging rate which is more than about 2/3 of the alternator capacity. ie if you have a 55amp alternator, do not set the charging rate higher than approx 30amps. This is to compensate for the fact that Boat Engine alternators are usually very poorly cooled." Don't shoot the messenger! That's just what it says!

That's an excellent description of how peer review is intended to work. However, there has been a lot of (justified, IMHO) criticism of how this process is actually applied, for example, in the IPCC. You can see the actual comments of sixty-nine of their Review Editors here. (big file, 1.4M) Please remember that these people are supposed to be reviewing THE most carefully prepared scientific document ever, one where "thousands" of scientists have pondered over every word. For those of you that can't be bothered to download the .pdf file, 64 of 69 Review Editor Comments consisted of standard forms with the words "yes", "yes", and "yes" inserted in replies to standard questions. Not too much "point scoring" going on here. Looks suspiciously like a "rubber stamping" process from where I'm standing.

Hi. I found the website for the Kestrel. http://www.acornengineer.com/kestrel_alt_controller.php As you can see, it's not a very sophisticated unit, but it does allow you to adjust the max charge voltage (and I certainly WOULD change this from the factory-set 15.5V) and the max charge current. I suspect that your current Adverc unit is better.

And what happens if 3 who reckon it'll blow up are really engine salesmen?

Hi Snibble. Don't worry - my wife says that I'm extremely thick skinned (or was it just thick?). I may have succumbed to the temptation of winding you up a bit, too, for which I apologise. I'm lighting the pipe of peace as we speak... In that case we have a lot in common. I've been shouted at by the QHM in Portsmouth!

It's a Kestrel K90 made by Acorn Engineering. I'm not sure if they still make them. I wouldn't recommend one to you, as, IMHO, the're not very good!

They're all loaded on the Thames. Wouldn't want to get their hands dirty on a wet and muddy anchor, so they just let it go, and then buy a shiny new one?

Chris - I agree, my alternator controller is a relatively simple, unsophisticated device. But it does have a charge current limiting pot. When you turn it, it does what it says on the tin. The max. charge voltage is set by a seperate pot.