24volts for Narrowboats

[madcat]

Ye Im up for a bit of a laugh and some leg pulling but I agree wiv Sir Nibble that there does seem to be a bit of argy bargy creeping in.I find these discussions interesting and feel that the situation just evolved for a lot of simple reasons and now we are where we are with 12v being the most common option.Most of us as the good knight suggests have the decision made for us by the starter motor on our chosen engine or with 2nd hand boats by the choices someone else made.

Now if you are starting from scratch and have a choice then you either do the research and make what you hope is an informed choice or take advice from them as really knows .

Anybody out there got 24v starting and 12v for cabin services?

Think if I wanted the keep it simple option I would go for 12volt system.

 

 

2cv could be a pig to start but the problem was crappy HT leads,look under the bonnet in the dark with the engine running.Fairies.

[Sir Nibble]

Ye Im up for a bit of a laugh and some leg pulling but I agree wiv Sir Nibble that there does seem to be a bit of argy bargy creeping in.I find these discussions interesting and feel that the situation just evolved for a lot of simple reasons and now we are where we are with 12v being the most common option.Most of us as the good knight suggests have the decision made for us by the starter motor on our chosen engine or with 2nd hand boats by the choices someone else made.

Now if you are starting from scratch and have a choice then you either do the research and make what you hope is an informed choice or take advice from them as really knows .

Anybody out there got 24v starting and 12v for cabin services?Think if I wanted the keep it simple option I would go for 12volt system.

Quite a few have I have passed on the part number for 24V start and 12V running relay to a couple of people.

An ocean racing yacht I was heavily involved in a while ago was specced for a 24V system but the engine electrics were 12V. The owners (sponsors? I dunno, the customer) wouldn't hear of a dual voltage system so they gave my old boss Satan a very substantial wedge indeed to have yours truly convert it. Starter armature had to be rewound but the largest cost by far was me poring over specifications to identify glow plugs, starter solenoid (pre engaged) and fuel shut off. The thing is that what really costs money is departing from standard. A boatbuilder will not grump at you demanding the unusual or unique, he's just sold a lot of labour to someone who thinks he knows better than an entire industry.

Edited September 1, 2009 by Sir Nibble

[Yoda]

They must be running 24v to power winches on fast sailing craft now. 12v motors would not have the torque to bring high strength sheets in.

[NB Alnwick]

I take the view that the guys who designed my boat and its engine knew what they were about - both were designed as 24v. Now, initially I did think that was a disadvantage because my 'Elecsol' cabin batteries were going flat far too quickly and needed a lot of charging - a few enquiries on here established that the batteries and charging circuits were inadequately wired (not by the designer/builder but by someone employed by the previous owner who increased the battery bank size) - this problem was fixed earlier this year and a SmartGauge was fitted - since then I have had no problems and the cheap second hand batteries (bought through this forum) are out-performing the 'Elecosols' that I paid five times as much for!

 

I haven't needed to buy any 12v equipment so I was completely unaware of the fact that it is easier to obtain than 24v stuff - and, as our local chandlery sells 24v stuff aplenty, it never really occurred to me that 24v kit was hard to obtain.

 

Now for an embarrassing admission - when searching for a 24v horn on eBay my search result produced all sorts or luxury cars - BMWs, Mercedes, Alfa-Romeos and the like. At the time I thought hmm, there seem to be a lot of 24v cars about these days - but this is not the case as I have only discovered since this topic started. In the case of those cars, '24v' was an abbreviation for 24 Valves!

 

Shows how easy it is to jump to a wrong conclusion . . .

Edited September 1, 2009 by NB Alnwick

[Sir Nibble]

They must be running 24v to power winches on fast sailing craft now. 12v motors would not have the torque to bring high strength sheets in.

All handraulic.

The auxiliary engine (gen and hydraulic pump) was mounted on rubber feet. the gen and pump were mounted on the hull. I told him that was a bad idea and he looked at me like I was dirt and waved his Bsc in my face. Test time and as soon as the engine was under load the rubber feet flexed and the belts went slack, much squealing and no generating or pumping. Same bloke specified 24V for no good reason and sourced things like desalination plant and electro-hydraulic power pack to suit then couldn't match it with suitable diesels. So I got the problem whilst he pretended it was all part of his master plan. Eventual solution to the APU problem was to fit idlers to the belts and seriously overtighten them so that they pre loaded the engine mounts. Disgraceful bodge, still, nice degree certificate.

[DHutch]

So if we already have a 24v boat (because it was the engine was fitted with 24v equipment) are you saying we should convert to 12v?

Not sure. But where does that leave someone who has a 24v boat with and engine that starts using safety matches and ligher fluid?

[madcat]

Dear Annick,nowt wrong with your 24v boat system ,as I understand your engine has 24v starter so 24v is the way to go.

Dear Dhutch a steam plant and DC electrics is my husbands idea of Heaven.Slightly smaller scale than TJ Harrisons old Craftsman but still steam.

Dear Sir Nibble I know absolutely nothing about racing yachts but your experiences show just what is lacking in university education,hands on practical experience.Hope Satan paid you well for your hard work but somehow I doubt it.We arent very good at rewarding people who actually get things up and running and keep things going.The big bonuses got to the numptys who run the whole job on the rocks , for numptys read bankers.

If its any consolation all this is a good distraction from face ache once Im fixed I will have to be getting on wiv a few jobs on the boat,will keep dropping back in though .

[Guest]

 

10V (one cell is dead in me battery).

Edited September 1, 2009 by Guest

[nb Innisfree]

You are out of order mate!

 

Richard

 

12volt

 

Yeah but it makes an entertaining thread!

 

Chris

 

24v!

[WotEver]

Chris

 

24v!

 

Oh yeah...

 

Tony

 

12v

[NB Alnwick]

I have necessarily removed some inappropriate posts to the archive. Unfortunately, this also means that where people responded to those posts the response has been moved too - but I hope you will all understand that this has been done in the best interests of the forum.

 

For future reference, however passionate we feel about a subject, it is not appropriate on this forum to accuse another member of telling lies or to indulge in an exchange of personal insults.

[Sir Nibble]

Little bit of cleaning up been going on I see.

Pirate Paul, putting on one of my professional hats as an NVQ A1 assessor in electrical engineering, I find you "not yet competant" pending further training.

My basic level 2 students would laugh you out of town.

Sorry Graham, but some folk simply don't deserve the protection of moderators when they are so offensively opinionated and entirely wrong.

[nb Innisfree]

I have necessarily removed some inappropriate posts to the archive. Unfortunately, this also means that where people responded to those posts the response has been moved too - but I hope you will all understand that this has been done in the best interests of the forum.

 

For future reference, however passionate we feel about a subject, it is not appropriate on this forum to accuse another member of telling lies or to indulge in an exchange of personal insults.

 

Spoilsport!

 

It was just warming up!

[NB Alnwick]

Wrong is matter of opinion until proven otherwise - there was a time when learned academics believed that the world was flat and that the moon was made of cheese . . .

 

By the way I don't believe either of those things but until today I did believe that 24v (volts not valves) was far more commonplace . . .

[Guest]

There's nowt like the magic of electrickery for starting the insults flying

[WotEver]

Little bit of cleaning up been going on I see.

 

Indeed. However I see no harm in stating that transformer losses include copper losses (I^2*R losses) in the primary and secondary windings, and the core losses (hysteresis and eddy-current losses) in the iron. These losses are the same whether operating in the step-up, step-down, or 1:1 mode. Hence, the efficiency is the same in any mode.

 

I could also add that an inverter running off 24v will draw exactly half the current of a similar inverter powering a similar load when fed with 12v. Same power is drawn from the batteries in either case.

 

I don't know why I said that; I just felt a need

 

... there was a time when learned academics believed that the world was flat and that the moon was made of cheese . . .

 

It's not?

 

Are you sure?

[Guest]

Indeed. However I see no harm in stating that transformer losses include copper losses (I^2*R losses) in the primary and secondary windings, and the core losses (hysteresis and eddy-current losses) in the iron. These losses are the same whether operating in the step-up, step-down, or 1:1 mode. Hence, the efficiency is the same in any mode.

 

I could also add that an inverter running off 24v will draw exactly half the current of a similar inverter powering a similar load when fed with 12v. Same power is drawn from the batteries in either case.

 

I don't know why I said that; I just felt a need

 

 

 

It's not?

 

Are you sure?

Use it for your signiature.

[Gibbo]

Wrong is matter of opinion until proven otherwise

 

 

Indeed. However I see no harm in stating that transformer losses include copper losses (I^2*R losses) in the primary and secondary windings, and the core losses (hysteresis and eddy-current losses) in the iron. These losses are the same whether operating in the step-up, step-down, or 1:1 mode. Hence, the efficiency is the same in any mode.

 

I could also add that an inverter running off 24v will draw exactly half the current of a similar inverter powering a similar load when fed with 12v. Same power is drawn from the batteries in either case.

 

And both these points have been proven many many times. They are both extremely common knowledge amongst people who actually know what they are talking about.

 

But along comes a newbie who think all the rest of the world is wrong because he actually stated that both the above facts were incorrect.

 

Which kinda gives a clue as to how much he actually knows.

 

Gibbo

[NB Alnwick]

And both these points have been proven many many times. They are both extremely common knowledge amongst people who actually know what they are talking about.

 

But along comes a newbie who think all the rest of the world is wrong because he actually stated that both the above facts were incorrect.

 

Which kinda gives a clue as to how much he actually knows.

 

Gibbo

 

When I went to school, we were expected to sit quietly and accept what we were told without question. As I grew older I learned that some of of the things that I had been taught had subsequently been proved to be wrong - that may be the reason why modern students tend to challenge information and this makes it a much harder job for those who have taken on the role of educating us.

 

These days experts can expect to be challenged and that is acceptable on this forum provided it is done in a civilized fashion without the need of exchanging personal insults. It is better to prove that someone is wrong (with a well reasoned argument and appropriate references) than to simply tell them that they are talking poo.

[RLWP]

It's not?

 

Are you sure?

 

Don't you listen to him. When I'm out using my spirit level, then I know the world is flat

 

Richard

 

For al practical purposes anyway

[Sir Nibble]

When I went to school, we were expected to sit quietly and accept what we were told without question. As I grew older I learned that some of of the things that I had been taught had subsequently been proved to be wrong - that may be the reason why modern students tend to challenge information and this makes it a much harder job for those who have taken on the role of educating us.

 

These days experts can expect to be challenged and that is acceptable on this forum provided it is done in a civilized fashion without the need of exchanging personal insults. It is better to prove that someone is wrong (with a well reasoned argument and appropriate references) than to simply tell them that they are talking poo.

Indeed so, and that is why my students are facilitated to prove for themselves what is and is not true. This is usual practice in further education these days learning by rote is long dead.

What gets my goat (and there seems to be a spate of it these days) is the assumption by others that they are uniquely enlightened. Electrical engineers in one form or another are not rare and to simply slag off and insult highly qualified and experienced people without giving any credence whatever to the notion that they just might know what they are talking about is crass in the extreme.

I wonder if pirate paul has a smartguage, that would be the ultimate irony.

[Guest]

Indeed so, and that is why my students are facilitated to prove for themselves what is and is not true. This is usual practice in further education these days learning by rote is long dead.

What gets my goat (and there seems to be a spate of it these days) is the assumption by others that they are uniquely enlightened. Electrical engineers in one form or another are not rare and to simply slag off and insult highly qualified and experienced people without giving any credence whatever to the notion that they just might know what they are talking about is crass in the extreme.

I wonder if pirate paul has a smartguage, that would be the ultimate irony.

I was just wondering:

 

1) Does he have an external reg. on his alternator?

2)What are his thoughts on earthing of hulls?

Edited September 1, 2009 by Guest

[alan_fincher]

I was just wondering:

 

1) Does he have an external reg. on his alternator?

2)What are his thoughts on earthing of hulls?

 

And surely, if he is to be taken seriously....

 

3) Does he have pump-out, or cassette ?

[NB Alnwick]

I was just wondering:

 

1) Does he have an external reg. on his alternator?

2)What are his thoughts on earthing of hulls?

 

Not to mention galvanic Isolation - oops