help with diodes and capacitors please?

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Old 04-17-11, 10:59 AM
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help with diodes and capacitors please?

Working on a high voltage electromagnet project. But i have a problem.

Here's the system: a 12 volt battery, connected to a 500 watt inverter. From the inverter there are two wires:

wire 1 goes directly to the negative on a capacitor series (5 electrolytic capacitors in the series each 400v x 470 uf) then directly to the negative on my high voltage electromagnet.

wire 2 is a bit more complicated. It goes directly to a series of diodes (3 diodes, wired in a series, each rated 800v x 16 amps). The arrows on the diodes are pointing away from the inverter going the direction of the current (thought that would allow current from the inverter through the diode, and prevent current coming back from the capacitor). From the diodes it then goes through an on/off switch, then to a throttle (controls how much current goes through), to the positive on my capacitor series, to the positive on the electromagnet.

But, seems there is a problem with the positive side of the capacitor series. Using a multimeter i can't read any voltage going through the diodes, and the circuit does not complete.

Are my diodes too large (yes, i wanted them large, big capacitor series)? Are the on the wrong wire? Help...

Fuelless Engine Plans 3 is a link to scribd, with a diagram of the circuit i am using for my project. Scroll down to the bottom of page 1 for the picture (pg 1 is actually the third page into the document).

Any ideas? I'm a moderate beginner.

Thanks a lot,

Isaac
 

Last edited by isaaca; 04-17-11 at 12:04 PM.
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Old 04-17-11, 11:40 AM
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It's been a long time since my basic electronics classes....but an inverter? You mean converting DC to AC? That just seems like it won't work.

We have a couple of very smart people on electronics...let them weigh in.

A drawing uploaded to a hosting site and then posted here, would probably be a big help....How To Put Pictures In Your Post - DoItYourself.com Community Forums
 
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Old 04-17-11, 01:13 PM
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Hi Isaac, as Gunguy stated a diagram will help a lot. I could not follow your description and since you are dealing with electrolytic capacitors you need to be sure they are connected correctly. They can go boom. See what you can post and we can comment better.

Bud
 
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Old 04-17-11, 01:34 PM
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Thanks guys, check out the link i edited in at the end of my original question. thanks again.
 
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Old 04-17-11, 02:01 PM
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Oh boy...another one of these. If you're doing it as a science project of some sort all well and good...but there's no such thing as a free lunch.

"and another type of energy I can not tell you about"...because it doesn't exist.

Good luck...
 
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Old 04-17-11, 02:07 PM
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yes gunman thank you. i'm more concerned about getting the circuit to be complete.
 
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Old 04-17-11, 02:21 PM
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when you put a one way diode on a an ac wire pointing the direction of the current, would that wire be in actuality a negative wire (since current flows from the negative to positive, though conventionally marked the other way around). Supposing i put a diode on an ac line (flow allowed out) would that wire then need to be connected to a positive or negative end of a capacitor?
 
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Old 04-17-11, 03:10 PM
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Hi again, I scanned your link, but did not see a schematic, at least one I'm used to. There are simple answers to your questions, but there is so much more to it that it is hard to provide safe advice.

I can talk you through some of this, but first tell me what you are building. Example, if you are building an electromagnet, it will be limited in capacity based upon many things, power applied being one.

You mentioned connecting capacitors in series and I did see a block diagram to that effect, however, it does not work to simply wire them as shown. The assumed purpose would be to increase the voltage capacity across the string of caps. But there are other components needed to assure that the DC voltage divides evenly. If not, then one or more caps will see a higher voltage and others will see a lower voltage. That higher voltage can exceed the rating for those caps.

To go further I will need more input.

Bud
 
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Old 04-17-11, 03:32 PM
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Thanks Bud,

I'm wanting to use the electrical system to turn on and off an electromagnet. The electromagnet will interact with permanent magnets on a flywheel (similar to electric starters on motors).

I am wanting to boost the voltage that will be going through the electromagnet - high voltage, low amperage - via the capacitors.

The idea is as follows: Using AC, I have a diode on one of the wires. This should keep the electrolytic capacitors charged quickly. The diodes should keep the current only going forward.

Right now my main question is regarding the wire with the diode. Would that wire connect to the negative or positive terminal on the capacitor? (I'm a tad confused because of the actual flow of electrons and the standard positive/negative designations on batteries).

When the wire leaves the capacitors, with voltage increased, the wire will go through an electromagnet. After the electromagnet, should the wire (being now DC correct?) connect to the capacitor bank or the 12 volt battery I am using so that the circuit is completed?

Thanks again,
Isaac
 
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Old 04-17-11, 04:59 PM
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Well, I don't know what to do. I mentioned the capacitors will not work or should not be connected as stated. The diagram you are looking at is just an illustration, not a schematic. They are saying you need to connect the capacitors in series to share the higher voltage equally across the combination, thus achieving a higher voltage cap. BUT, they are not showing you how that is done, ie there is more circuitry involved. Similarly, the rest of the information you are following is not complete enough to start wiring things together and you obviously do not have the background to complete the design.

I must apologize, but because I cannot be sure what you are doing is going to be safe I cannot offer additional advice.

You sound interested in electronics so don't let me discourage you. To get you started, current flows with the arrow on your diodes, but electron flow goes in the opposite direction. Try searching on "half wave rectifiers", then kick in High voltage to that search and do some serious reading.

Bud
 
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Old 04-17-11, 10:24 PM
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Originally Posted by isaaca View Post
Thanks Bud,

I'm wanting to use the electrical system to turn on and off an electromagnet. The electromagnet will interact with permanent magnets on a flywheel (similar to electric starters on motors).

I am wanting to boost the voltage that will be going through the electromagnet - high voltage, low amperage - via the capacitors.

The idea is as follows: Using AC, I have a diode on one of the wires. This should keep the electrolytic capacitors charged quickly. The diodes should keep the current only going forward.

Right now my main question is regarding the wire with the diode. Would that wire connect to the negative or positive terminal on the capacitor? (I'm a tad confused because of the actual flow of electrons and the standard positive/negative designations on batteries).

When the wire leaves the capacitors, with voltage increased, the wire will go through an electromagnet. After the electromagnet, should the wire (being now DC correct?) connect to the capacitor bank or the 12 volt battery I am using so that the circuit is completed?

Thanks again,
Isaac
These things have been tried and debunked time and time again. This is a "perpetual motion machine", and you will never get it to work. DO NOT spend any money on building one. The crackpot conmen behind these 'inventions' claim to be suppressed and persecuted by governments and oil executives. The only thing suppressing them is physics. They violate the First Law of Thermodynamics. They are all nothing but a scam.
 
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Old 04-18-11, 09:39 AM
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Bud,

Having a friend of mine who's an electrician help me convert the AC to DC at high voltage. Probably the full wave rectifier.

JerseyMatt,

Thank you for your constructive cynicism and please note I am not trying to build a perpetual motion engine. Just a simple motor.
 
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Old 04-18-11, 09:59 AM
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Originally Posted by isaaca View Post
Bud,

Having a friend of mine who's an electrician help me convert the AC to DC at high voltage. Probably the full wave rectifier.

JerseyMatt,

Thank you for your constructive cynicism and please note I am not trying to build a perpetual motion engine. Just a simple motor.
Ok, whatever you say.. That's why you linked directly to one and are asking questions regarding the vague, cryptic sounding instructions that are typical of one.. A battery powers a motor through a cycling circuit which drives a flywheel with permanent magnets that excites electromagnets around it (otherwise known as a generator) which in turn recharges the battery through a "capacitive boosting circuit". Yeah I get it. So how is that not a perpetual motion machine?
 
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Old 04-18-11, 10:20 AM
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Originally Posted by isaaca View Post
Supposing i put a diode on an ac line (flow allowed out) would that wire then need to be connected to a positive or negative end of a capacitor?
hmmm, the "arrow" on the diode schematic "points" to current flow, the opposite of electron flow. so, it will "point" to the + end of your capacitor bank. You should equalize series capacitors in these type of circuits, so the DC voltage will tend to be the same for all. Beyond that, I can't make heads or tails of the "schematic" in that link, and I've see and made quit a few.
 
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