Alternator Paralleler Circuit

[alan_fincher]

4 note down all the silly numbers

5 try to get all the silly numbers right on this site

Why ?

 

Most of these sites like photo-bucket create an tag and put it, (along with things like links), with the stored image.

 

You simple cut and paste the tag into Canal World - no need to note down or re-type anything at all.

 

I imagine the reason the forum owner, (who personally sponsors this site from his hard earned cash), wants you to do it that way is so that someone else is paying for the storage of all the images in use, rather than him.

 

It really isn't hard.

[Sir Nibble]

I just drew a diagram in "paint" and tried to upload it to the gallery but it says "you are not allowed to upload this type of image".

 

OK, the domestic alternator connects to the domestic batteries.

The output from the engine alternator connects to 3 diodes, one is backfed to the field +ve on the regulator and thence to + brush. The alternator senses on this and therefore the diode voltage drop is compensated for. The other 2 diodes are connected each to one of the batteries.

Turn on, warning lamp current flows to the field and alternators excite and cut in. The domestic alternator begins to charge the domestic battery. Voltage is say 13.5 and alternator is delivering full whack to try and drive it higher.

Engine alternator is regulated at 14.2 but is also unable to drive the domestic voltage (Via the diode) that high and so is delivering full whack to try to do so. Engine battery is also recieving a small charge.

Domestic battery voltage slowly rises until it reaches 14.2 and engine alternator begins to regulate. Domestic alternator is set at say 14.6 for the sake of argument regulated by a sterling pdar, and so until voltage reaches this level it continues to run flat out. Output from engine alternator slowly falls until voltage on domestics reaches 14.3 at which point all the engine alternator output is flowing to the engine battery alone and the domestic alternator is working flat out until 14.6 is reached and the acceptance phase begins.

 

Hope that's clearer.

[carlt]

I just drew a diagram in "paint" and tried to upload it to the gallery but it says "you are not allowed to upload this type of image".

If it'll allow Tomsk's cake circuit diagrams surely a bit of Dulux would be okay?

[Sir Nibble]

If it'll allow Tomsk's cake circuit diagrams surely a bit of Dulux would be okay?

Don't shoot the messenger carl, you know what it's like "those shoes are casual mate" not open to debate.

[blackrose]

I haven't really been following this thread as my start battery alternator is also used to charge my BT batteries, so for me it's already being utlilised sufficiently, but I spoke to Chris W on the phone the other day and after a recent 6 week trip he told me he's had some great results from his paralleler circuit.

Edited September 3, 2009 by blackrose

[tomsk]

I was hoping to provoke a stimulating discussion on whether the current trend of introducing aftermarket liquorice wheels into the circuitry was acceptable practice, or if in fact like for like O/E Pontifract Cakes were the only way forward (in regard of over-voltages ect) when renewing the componentry used in this most specialised of applications. As side issue, would our experts view cheese strings as acceptable for use as a CPC when rewiring my house in a savoury style, and if so what should its cross-sectional area be and furthermore, would its use preclude my ability to have a 17th edition Electrical Installation Certificate issued against the exciting new installation?

[Sir Nibble]

Tomsk, You MUST avoid high fat conductors in domestic installations in order to avoid structural obesity. Check pattern licorice wheels carefully as some have been imported in recent years with poorly spot welded hundreds and thousands. A good savoury alternative is sliced pepperoni enabling jacobs crackers to be paralleled with pizza, but they should be fused with licorice allsorts.

Now f*ck off, you're too stoned.

[tomsk]

Tomsk, You MUST avoid high fat conductors in domestic installations in order to avoid structural obesity. Check pattern licorice wheels carefully as some have been imported in recent years with poorly spot welded hundreds and thousands. A good savoury alternative is sliced pepperoni enabling jacobs crackers to be paralleled with pizza, but they should be fused with licorice allsorts.

Now f*ck off, you're too stoned.

 

Many thanks for your wise counsel.

[WotEver]

I just drew a diagram in "paint" and tried to upload it to the gallery but it says "you are not allowed to upload this type of image".

 

Will this do?

 

T

[Gibbo]

28 pages but got there eventually!

 

I do believe that is the best solution. Certainly the most elegant, and unless I have a negative Eureka moment I think it's bloody brilliant and does exactly what was intitially wanted.

 

Gibbo

Edited September 3, 2009 by Gibbo

[Sir Nibble]

28 pages but got there eventually!

 

I do believe that is the best solution. Certainly the most elegant, and unless I have a negative Eureka moment I think it's bloody brilliant and does exactly what was intitially wanted.

 

Gibbo

Aw shucks

Yea, half the lines are missing as I see it but that's right.

Now wait 'till Chris sees it and the roller coaster will be off again!

[pistnbroke]

I thin that is excellent ...the only thing it does not do is let the start battery come up to full voltage first but a heavy duty switch in the top diode feed to the domestic battery ,thrown after about 10 min of running sorts that and it does not matter if its forgotten when you turn off the engine

 

 

Dont forget you have to disconnect the field diodes inside the alternator !!!!![/b]

[Chris Pink]

The output from the engine alternator connects to 3 diodes, one is backfed to the field +ve on the regulator and thence to + brush. The alternator senses on this and therefore the diode voltage drop is compensated for. The other 2 diodes are connected each to one of the batteries.

 

What rating on the diodes?

 

Would something like the Sterling 1 in 3 out unit fit the bill (retails around £40 for 70A).

[Sir Nibble]

I thin that is excellent ...the only thing it does not do is let the start battery come up to full voltage first but a heavy duty switch in the top diode feed to the domestic battery ,thrown after about 10 min of running sorts that and it does not matter if its forgotten when you turn off the engine

 

 

Dont forget you have to disconnect the field diodes inside the alternator !!!!![/b]

Yes the original idea did say that the input from the field diodes must be isolated and the warning light must also be connected to the new F+ connection. I'm not too worried about the engine battery since it's working regime is heavily biased towards charge. If your starter draws 300A for 10 seconds (and that's a massive draw for a lot of cranking erring heavily towards the top end) that's still only 1Ah which don't take much to put back.

With some alternators you could clear the field diodes by shoving a B+ on the W and a B- on D+ until the smoke stops, but I didn't say that!

[WotEver]

With some alternators you could clear the field diodes by shoving a B+ on the W and a B- on D+ until the smoke stops, but I didn't say that!

 

No... you should never allow the magic blue smoke to escape from anything electrical...

 

T

[Sir Nibble]

What rating on the diodes?

 

Would something like the Sterling 1 in 3 out unit fit the bill (retails around £40 for 70A).

A standard split charge block. Part numbers in post 543.

I only have a single alternator myself so if anyone actually does this I would be very interested in comparative performance figures.

[smileypete]

28 pages but got there eventually!

 

I do believe that is the best solution. Certainly the most elegant, and unless I have a negative Eureka moment I think it's bloody brilliant and does exactly what was intitially wanted.

Thought you weren't a fan of split charge diodes?

 

http://www.smartgauge.co.uk/diodes.html

 

cheers,

Pete.

[Smelly]

So... many moons ago I threateneed to ask the mods to filter out the chaff in order to share the goods...

 

Is it time???

[Gibbo]

Thought you weren't a fan of split charge diodes?

 

I'm not. They're absolute and utter sh*t. Complete and utter cr*p. Totally hopeless for split charging. They waste power, mess up the alternator regulation voltage, lead to over and/or undercharging and make a complete and utter mess of everything one is trying to do with a split charge system.

 

But this isn't a split charge system. This is a way of diverting the spare capacity from one alternator to the other battery bank for a small portion of the charge time. Completely different bag of fish.

 

Because I know that split charge diodes are rubbish, doesn't mean diodes don't have other uses.

 

Gibbo

 

So... many moons ago I threateneed to ask the mods to filter out the chaff in order to share the goods...

 

Is it time???

 

Well that's easy. Delete every single post in the thread apart from #559 and make sure Nibble gets the credit.

 

Gibbo

[Sir Nibble]

I'm not. They're absolute and utter sh*t. Complete and utter cr*p. Totally hopeless for split charging. They waste power, mess up the alternator regulation voltage, lead to over and/or undercharging and make a complete and utter mess of everything one is trying to do with a split charge system.

 

But this isn't a split charge system. This is a way of diverting the spare capacity from one alternator to the other battery bank for a small portion of the charge time. Completely different bag of fish.

 

Because I know that split charge diodes are rubbish, doesn't mean diodes don't have other uses.

 

Gibbo

 

 

 

Well that's easy. Delete every single post in the thread apart from #559 and make sure Nibble gets the credit.

 

Gibbo

 

I've given this some thought.

First, I agree with all that Gibbo has to say about split charge diodes, and also why this applies to a lesser extent in this case.

I can be pretty sure that all the other professional electron herders on here would agree that there is a strong case for that conclusion.

And there in my opinion is the issue. For 28 pages we were guilty of blinkered thinking and we should take note of that. As for the eventual consensus solution, Look at it! C'mon that's way too simple to be original! And anyway, it was a natural consequence of someone, was it Arnot? dunno, apologies for forgetting, suggesting bringing 3 phase leads out and a seperate rectifier.

 

I will just repeat, I would LOVE to see it done and hear the results.

[WotEver]

Well that's easy. Delete every single post in the thread apart from #559 and make sure Nibble gets the credit.

 

Keep #552 as well, and not only does Snib get the credit but we get the explanation too.

 

T

 

it was a natural consequence of someone, was it Arnot? dunno, apologies for forgetting, suggesting bringing 3 phase leads out and a seperate rectifier.

 

I think that was Pete in #473, here.

 

T.

[Smelly]

Issue... If the engine battery is dead and the domestics are not, would trying to start the engine and hence draw BIG current across the diodes the wrong way cause problems???

 

If not, with silver linings in mind (or possibly solutions) if the contactor is parallel to the diode pack, and fed from a switched source, then it can retain engine start capability from the domestics. If anyone's not already got the contactor then a jump lead's quicker and cheaper, but for those of us that have...

Edited September 5, 2009 by Smelly

[pistnbroke]

so Smelly we will treat all your electrical posts with suspicion from now on

 

Current cannot go THE WRONG WAY through a diode and current goes through not accross things ( thats voltage )

 

No problem will be caused by using a jump lead or equivallent but leave it in place for a few minutes to let the start battery come up a little ....

[Smelly]

so Smelly we will treat all your electrical posts with suspicion from now on

 

I'm the first to admit that my knowledge is all accepted and sometimes by asking stupid questions... If you don't ask you don't learn...

 

Having thought about it a bit more I've never heard of a burned out split charge diode so I'll concede it was a daft question on the evidence of experience; although i still wonder whether putting a large inductive load on the wrong side of a diode might be bad for it, I know b*gger all about diodes apart from their effect, but at the time it struck me as something that needed pondering.

[Gibbo]

...................I've never heard of a burned out split charge diode..............

 

Me ribs.

 

Gibbo