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# Schematics Variable current 12v 60A to 0A

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Dazza,

This is a good overview to start from.
I have been thinking about the variable voltage alternator, you can have some unwanted effects form a setup like that. It will be sensitive to which rpm it runs at since there is no battery for

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Yes ante, I am at a bit of a loss, on how to tackle this problem. If we were to add a large capacitor, we would be asking it to do the job, of a battery. I am thinking that this will be a capacitor of very high capacitance very expensive. Would a recycled capacitor. from a microwave be able to be used, what do you think I could be doing here ante? Yes ante, I can see your catch 22 scenario. There is something that I have left out of the block diagram, that will help (lessen some) of these problems. A device between the pressure sender unit, and the adjust pulse width 12V to 24V. the idea of this device is to (dampen) the possibly fast reaction of the pressure sender, if pressure was to drop dramatically, because of demand from the engine for the hydrogen. So the dampening effect is needed, to lessen the demand on the rest of the system, to respond so quickly. now implementing this dampening effect, will mean there isn't adequate hydrogen to supply the engine. So to fix this problem, a small storage chamber, immediately after the reactor chamber, to hold enough hydrogen for these extreme demand hydrogen fuel situation. For example a vehicle towing a heavy trailer, overtaking a vehicle up hill. This hydrogen chamber, I believe will not need to be much larger, than the supply line itself. Therefore not being a significant storage risk. Now that being said, I do fear using higher voltage, could result in the possibility of arcing, within the hydrogen chamber of the reactor, if the separation of hydrogen and oxygen is less than perfect. So I need to apply caution here, the water will have an additive to it to make it more conductive, and the higher the voltage,the more opportunity there is, for a spark to jump between the electrode, and in respect of the electrode spacing. If I could be sure, that there was only hydrogen within this part of the chamber than a spark would not result in ignition. Now realising this possible risk, in using higher voltage, I feel that the maximum of 24V, should keep me safe.

Now am I understanding this right ante. I have a 12V alternator I am wanting it to produce upwards to 24V. so to achieve the higher voltage. I will be compromising the amperage output. Now this is in respect of the number of windings, within the alternator stater, which will ultimately limit my voltage output. I have read on the Internet that 110V is quite possible, with of course the compromise of the amperage output. So if I was to discover the ideal voltage for this system, to be say 17V. I could then modify the alternator, to be ideally suited for this situation in respect of, the thickness of the wire, to the amount of turns required, and of course the RPM the alternator will require. ante, the information in the link you provided, will prove to be very useful in this project.

I was surprised to find myself in the top 15 post. I would say you would have hit the 1000 post by now ante, my question is, do you get to choose the colour of that free LED ;D ;D.

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Dazza, Yes a big cap is expensive and a microwave cap is rated for high voltage but it

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Hi Ante,
Your prize will make "only" 16M colours, and its white will be much better than a white LED.

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Thanks Audioguru,

That

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Ante, I don't like it when you say, I don't know. I think from now on this phrase is reserved for me only ;D ;D.
Ante can you suggest the type of equipment, that I am likely to find large capacitors in.

Ok using large capacitors should solve the problem, of having some power available to supply the reactor, while giving enough time for the regulator alternator to respond. I am a bit worried about what will happen, when the reactor is drawing its maximum current, and then wants to reduce down to zero rapidly, I can see a situation where there is a lot of current width nowhere to go. Ok having a dampening effect will help. Ante, can you think of any way of dealing with this excess current with nowhere to go.

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Dazza,
Man, there are lots of things I don

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Ante, at our local tips we have recycling plants, and dump rats as they are known as. These are people who own the scavenging rights, and sell anything and everything that they find, that may have some value. I'm a little reluctant to pay good money for something, and find after I've taken it home and pulled it apart, that there is nothing useful in their, and then I give it back to them for free, by throwing it in the rubbish.

Ante, I have yet another question about paralleling components. I asked about the chohe, for the reasons that if I can't get one, that can handle the current. Can diodes be paralleled for the bridge rectifier. I can get a hold of plenty of diodes from old alternators for next to nothing, and parallel them to handle the current.

Ante, I think it is called CAPCAM. 8)

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Ante, I have a question about the six diodes, for the three-phase. If my maximum current was to be 200A, what would the maximum amperage need to be for each diode. Would it be about 33A four each diode, plus a little headroom.

Dazza, aren

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Ante, I just had an idea on solving the problems with the regulator, in keeping the 12 volt battery isolated, from the varying voltage. Does this looked like it will work in principle. I have basically isolated the stator from the field coil. It's a bit muddy at this stage as usual ;D.

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Ok, where do I start? Well I think R1 is not supposed to be paralleled with the wire that comes from Q2: s collector!? The inverting input of U3 (pin2) will not have any reference besides the voltage from R1 (floating?) and U3 will die from a voltage this much higher than its supply I guess. Q5 will have to carry all the current for the pre start reaction

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Ante, I think I know how I have to go about this now. I'll say that again I think ;D. I'm going to start from scratch, instead of trying to modify these schematics and making a big mess. I have the first schematics that I modified in front of me, as well as the one I just posted, I am starting to see how I can make it all work. And with any luck I won't make your head spin again :o. Well maybe just a little ;D.

I think I might use two relays one in place of Q5, and the other one for the negative return to the battery from the reactor, these two relays can be then turned on to supply power to the reactor for start-up, and then switched off by the RPM sensor. I think using relays here will solve a lot of problems.

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Dazza, Lets try to build one module at a time and interface them together along the way one by one. Then we take care of the different issues as they intervene. What do you think? ;D

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Ante, I think you are right 8). I'm still trying to find my feet, on the best way to go about developing and putting together these circuits :P. Well this is the result of starting over from scratch. The three relays are activated together by the RPM sensor switch via W3. RLY3 is there to stop the field coil receiving any current until the engine is started. RLY1 and RLY2 is there to allow 12V to the reactor for start-up, and once started switched on by the RPM sensor switch, to isolate the 12V from the high voltage supplied by the alternator to the reactor, U4 and U3 are now supplied by the 12V battery. Well I think this is looking a little better, what do you think ante. Have I made things better or worse ???.

Dazza, Yea we

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Ante, the collector of Q2 should be going to the positive side, I really should not of made that mistake :-[. R4 was in the original circuit, I thought the same thing why is it there, maybe it had a function in the original circuit, I wasn't sure so I left it :-\. Yes SW1= ignition switch. Yes automotive relays for RLY1 and RLY2 they are cheap and I have a few laying around. You say it's a good idea to use diodes just to be sure with relays in a circuit, that makes sense to me why take the chance 8).

Ante, I'm not sure what you mean when you say

(Can you walk me through it so I know how ;D (if) ;D you are thinking please?)
Are you asking me to explain( walk through) how I am wanting this circuit to function, or how I am wanting it to function with Q2 collector connected to the negative side of the alternator, which is a stupid mistake. I wish I could promise I wouldn't make those sort of mistakes again, But I will do my best :).
(Is the positive output suppose to attached to the field coil)
I'm not sure what is wrong here ante, this is wrong? Can you see a better way.

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Dazza,

Yes, a walk through was what I meant. Sorry if I was blurry. I noticed that you are charging the 12V battery from the alternator. This alternator is at the same time used at up to 24Volts, am I on track? Q2 will not survive the current here I am afraid. :o I would be better to have a separate alternator for 12 V if possible (Is it possible?) or there must be a current regulation also or insted. You are trying to control the output current from the alternator, the normal way is sensing the output voltage and control it by exciting the armature winding. In this case you are already using the armature coil for a different regulating purpose.
And everybody makes mistakes so don

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Sorry ante, you can't claim the prize for being blurry, I am clearly the winner ;D. Yes ante I want to use the same alternator to maintain the charge of the battery, you are on track. Yes a second alternator would be possible, but I desperately do not want to do this. How can I incorporate a current limiting circuit for keeping the battery charged.

The battery is there to supply power to produce hydrogen for start-up, as well as good stable power for any other electrical device needed in this system. So I'm wanting to keep the alternator isolated as much as possible, from anything else except to supply power to the reactor, and maintain charge to the battery.

Maybe what I'm trying to do, is something that can't be done the way that I want. This is my downside, their is so much I just don't know :-\.

I hope you don't lose patience with me ante.

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Dazza, It can be done but not with good efficiency, it should be possible to charge with constant current. There will be heat losses because the voltage is sometimes twice the needed for charging a 12V battery. And it will work only as long as the voltage from the alternator is higher than a certain point and will supply nothing if below. This involves of curse more electronics and it will not simplify the construction. Why are you desperate not to add a second alternator? ??? I am a patience man don

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Ante, adding an extra alternator to most vehicles can be difficult, but not impossible. But adding two extra alternators can prove to be a real challenge for any vehicle. This is why I think a solution to this problem at this stage would be a good idea. Trying to keep component count down is always a good thing, but sometimes unavoidable. My powers of innovation in this area, electronics aren't so good ante. if it is going to work with a hire component count then this is how it has to be. Maybe later on down the track, another solution may be found.

You say that efficiency will not be so good, this is not a good thing for a system like this, poor efficiency is our enemy. Can you give an idea on what amounts of energy will be lost. We may be able to view the energy loss as a necessary evil four the time being.

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Dazza,
Why two extra alternators, you already have one in a vehicle and you have the battery? Or you are going to create a second 12Volt system just for the reactor? Then I can see why it will be tight under the hood (or maybe you say bonnet)? OK about the efficiency, unfortunately there will be losses and they can vary depending on several factors. How much charge is necessary to keep the battery in shape, how big (Ah) is the battery? How much of the time will the voltage from the alternator stay in the high range? The constant charge regulator will have a voltage controlled limiting circuit not to overcharge. Furthermore there will be no charging below about 15 to 16Volts, the constant charging circuit will not work at lower voltage. An example, we have chosen to charge at 15A and the battery is after starting at 11Volts. The reactor needs full boost (full throttle on the way to a sale) alternator puts out 32Volts. A calculation show ((32

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Ante, my original idea when I started this project, was to use a separate alternator and battery. One of the reasons for this was if something was to go wrong electronically, it wouldn't give an opportunity to damage any of the original electrical systems of the vehicle. Since I started this project I have learnt a lot, and a lot has changed from the way I originally wanted this system to work. One of the things I have learnt is just how difficult it can be to make something work a certain way, especially when there is a lot that I don't understand. So from where we are now with this project, we can use the vehicles existing battery to supply power to the electrical system, as well as the power for start up. The second alternator will be kept isolated as much as possible, except for supplying power to the reactor. This is looking a little easier. Maybe now I won't need to jump up and down on the bonnet/hood,

Ante, I'm feeling confident I can put these circuits together, and see how they go. I have one more circuit I would like to have on the drawing board, before I put in an order for every think that I need from farnell. Eventually the pressure sender unit on the hydrogen output side of the reactor will control the PWM. As I mentioned before, I will need a device that will give a dampening effect. When the pressure drops quickly the sender unit will force the PWM to respond quickly, and in turn the alternator and regulator. I can see this being a problem, and an unnecessary demand on the system. So when the pressure drops quickly. Due to demeaned for hydrogen from the engine, the pressure sender unit will force the PWM to respond accordingly, so this device will need to prevent the PWM from responding so quickly, creating the dampening effect,I hope you get what I mean. Much like the effect of a shock absorb on your car.

Dazza,

I don

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ante, pressure sender switch, to me and others I have worked with in the mechanical area, means when a temperature or pressure reaches a certain point, it turns on or off(receives no change in State until a certain point). And a pressure sender, means it sends a signal corresponding to the temperature or pressure that it is at. So I should be saying, pressure transmitter? Instead of pressure sender.

One, pressure transmitter will control the PWM. so it's varying voltage that corresponds to the pressure in the hydrogen line will control the power to the reactor via the PWM. I will also need another pressure transmitter, as a safety shutdown, to detect whether the pressure is too high or too low, and another safety shutdown to work in the same way for the reactor chamber, this is in case the one-way valve between the reactor chamber in the hydrogen line became blocked.

I like the way you are on the ball with safety ideas ante, I also have a mechanical over pressure release which will also release an enormous amount of energy, if the worst was to happen and there was an ignition spark within the chamber. As for where to release the hydrogen in such an event. Interesting enough it is extremely difficult to ignite hydrogen once released into the atmosphere. If you were to release hydrogen and turn off the source, and quickly try to ignite it,it is very very unlikely it would. The reason is, that hydrogen dissipates into the atmosphere extremely fast. If it was LPG leaking from under your hood, the danger alarms should be ringing. But just to make sure an electric fan can be used, that can be switched on in the event of a shutdown to help dissipate any released hydrogen,or the safety shutdown could be linked to the existing cooling fans of the vehicle on the radiator if fitted. There is another safety device idea that I have, but I am pretty sure this would be very difficult to put together and best left to a later time. The basic idea is although I do not want to attend it at this stage, is to compare the difference between RPM, hydrogen pressure and current being drawn by the reactor. At any given RPM the other two variables should correspond, within a certain degree range of error.

For now ante for experimenting, I can get away with one pressure transmitter, in the reactor chamber only water here, I won't use a one-way valve so the pressure in the hydrogen line and in the reactor will be the same, later on I will have to come up with the cash for a proper sender transmitter designed for hydrogen, these are available but cost an arm and a leg. Sorry for sending you astray ante, that sure is good for off the top of your head 8), I'm pretty sure I can use that circuit with the heat exchange system :).

You are pretty much on track, which is a little surprising considering how bad I am at explaining things :-\.

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