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Old 05-05-2006, 03:31 AM   #46
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To correct some info here. High Voltage is not dangerous unless it's accompanied by high Amperage. It also works the other way around to high Amperage is not dangerous unless it's accompanied by high Voltage. This was repeatedly proved by Nicolai Tesla. For electricity to be dangerous it has to have both high Voltage and Amperage.
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Old 05-05-2006, 12:01 PM   #47
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people have died from electric shocks with as low as 32 volts due to high amperage.

Even 10 volts at 1,000 ohms at 10-20ma can be strong enough that if you touched it you couldn't let go...

I guarantee that if you touch the wrong items in a magnet zapper you will get hurt. Under the right conditions a magnet zapper can definately be lethal as well. They are all built different some might be higher voltage some higher amperage etc.

I would say find an electrician to help you out at the least before you attempt to build one.
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Old 05-05-2006, 12:26 PM   #48
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thanks for the advice
I have a couple of friends who are electrical engineers currently working on the size of coils and capacitors to use so progress is being made
a wiring schematic I have allready got
manufacturers would have people believe that it is some kind of black art but it isnt
i was allways told when growing up
"dont let anyone tell you it cant be done !"


and theres only 2 things smell like fish and one of them is fish !!!
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Old 05-05-2006, 12:57 PM   #49
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Its not a black art its called Science and trial and error.
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Old 05-05-2006, 05:11 PM   #50
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Quote:
Originally Posted by andsetinn
To correct some info here. High Voltage is not dangerous unless it's accompanied by high Amperage. It also works the other way around to high Amperage is not dangerous unless it's accompanied by high Voltage. This was repeatedly proved by Nicolai Tesla. For electricity to be dangerous it has to have both high Voltage and Amperage.
There is a misconception about the dangers of current and voltage.

As engineers we are always concerned with the safety of the user and consumer. I make this correction to your statement that it takes a HIGH VOLTAGE AND CURRENT to be dangerous. This is INCORRECT, and I only say this to avoid an accident.

Please understand that it is not the high voltage or the current that makes this lethal, it is the combination and discharge time.

It is not the voltage or the current alone that we look at. The danger is the amount of JOULES (ENERGY) that get transferred. A JOULE is a WATT-SECOND. You can produce as many JOULES as you want at any desired voltage.

We are talking about capacitive discharges here, so here is some advice:

To measure the JOULES that capacitor bank puts out you use the following formula:
JOULES= (C/2)*V(square)
Where C is in FARADS.
V= Voltage

So for example if you have a circuit that has an 800,000 uf capacitor charged at 18 volts you will generate 130 Joules. This WILL HURT YOU!!! ...and put a hell of a BURN on your body. Also, the current transferred by this can be in excess of 500amps in less than a few milliseconds. If this energy was to go through your body, you would get a hell of a jolt and most probably your heart could stop.

As I said earlier, it only takes less than 25 Joules to punch a hole and generate lots of sparks through aluminum foil and you can weld a small wire with 40 Joules.

***Lets assume that an r/c magnet zappers works at around 120 volts, and it is using a 10 Farad capacitor bank, then the energy being transferred by the discharged capacitor will be 72,000 Joules. This will generate in excess of 5,000 AMPS and it will be transferred in less than 700 milliseconds
That is a TON of ENERGY.
The Joules generated by the capacitive discharge zappers can be in the thousands…and the current could be in excess of 20,000 amps. With a transfer time of milliseconds.
***This is only an example

Do you know how many Joules it takes to restart a heart? Pay attention next time you watch ER when they say, "CHARGE TO XXX JOULES” You will be surprised at the charge. It is minimal compared to this.


Please be careful when working with capacitors and coils if you do not know what you are doing. It is best you ask for advice from those who work with this on a regular basis.

Last edited by BATT_MAN; 05-05-2006 at 05:54 PM.
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Old 05-05-2006, 05:28 PM   #51
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Quote:
Originally Posted by Tempest2000
Its not a black art its called Science and trial and error.
with very dangerous errors
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Old 05-05-2006, 05:49 PM   #52
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Here is a SAMPLE CAPACITIVE DISCHARGE GRAPH.

This graph is the representation of the example that I talkd about in the previous post.

This is just to show the relation of Voltage, Current, and Time.

As anyone can see, the CURRENT IS EXTREMELY HIGH (above 5.8KA) and DANGEROUS.

I hope this helps to visualize the POWER and ENERGY that can be delivered by 120 Volts with a 10F capacitor bank.

An assumption for very low resistance is made.
Attached Thumbnails
Motor Zappers-cap_disch_sample.jpg  
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Old 05-05-2006, 08:08 PM   #53
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Quote:
Originally Posted by Mrshells
thanks for the advice
I have a couple of friends who are electrical engineers currently working on the size of coils and capacitors to use so progress is being made
a wiring schematic I have allready got
manufacturers would have people believe that it is some kind of black art but it isnt
i was allways told when growing up
"dont let anyone tell you it cant be done !"


and theres only 2 things smell like fish and one of them is fish !!!
Mrshells,

I am glad to hear that you are progressing on your magnet zapper.
However, please note that the electronics are the easiest part of the design.
In order for your zapper to work properly the magnetic fixture has to be designed just right, otherwise the magnetic flux density and flow patterns will not over saturate the can.

There are several ways to go about it. One is trial and error, but that can get very expensive, as you will be machining lots of parts until you get it right.
The other is to consult with a magnetism specialist or physicist (nuclear). Their help can guide you in the right direction and minimize lots of errors and time.

Believe me; the magnetic fixture is critical to the success of your zapper.
I wish you the best of luck on your venture.
Should you need any help do not hesitate to call on me.

I hope this turns into a successful project for you.
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Old 05-06-2006, 02:21 AM   #54
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Most engineers will tell you that just because an equation says something will work doesn't mean it will work to your expectations in real life applications.

I can make a zapper that looks great on paper, but without the specific experience in the field of magnetics you will spend a great deal of time with trial and error getting it right. More than likely an engineer will make a working magnetizer. However I would bet that 9 times out of 10 the first version will not fully saturate the magnets. It might slightly improve them, but it won't fully reverse and then fully resaturate the magnets in the proper orientation which is the only true test that matters for our application. If it can't reverse the magnets fully and then bring them back to the appropriate orientation then the design needs work.

Call it black magic if you want, but real world experience plays a part in any form of science.

Time, testing, and experience are worth something in any field of work. Why should we just give out information that we spent 100's or 1000's of hours learning and developing?

That's like asking Competition Electronics to give out their schematics and eprom information because we think it should be cheaper and that we can make it ourselves and save some money.

Does a charger or a dyno really cost what they charge to build? of course not you are paying for the intellectual rights as well. Not to mention labor etc.

Ask any business to just hand over their intellectual property. You'll be laughed right out the door.

Just because this sport is a hobby doesn't mean that our businesses aren't real.

If it was as easy as people think there would me more magnet zapper manufacturers.

Most people remember a company called ERP Edurance... they made two versions and neither one worked. One actually had specs on paper that should have at least partially worked, but they screwed up the return path and the pole shoes as well. They sold a bunch of units and ruined the market for years because no one believed magnet zappers actually worked.
Their units actually demagnetized the motors in most cases.

They had engineers design those units and they didn't work at all. Well they were handy paper weights.

There is no doubt it can be done its been proven.
I do know when its all said and done you will have spent more time and money than you could have just bought a magnetizer.

Best of luck

Michael
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Old 05-06-2006, 10:59 AM   #55
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Quote:
Originally Posted by BATT-MAN

For those that want to get their magnets zapped, I recommend to either purchase a reliable unit or send the can to someone that owns one. It will be safer and cheaper to do this than to use a home made magnet zapper....
Quote:
Originally Posted by Tempest2000

There is no doubt it can be done its been proven.
I do know when its all said and done you will have spent more time and money than you could have just bought a magnetizer.
I AGREE WITH YOU.
It is obvious that we share the same philosophy regarding this issue.

I only made the recommendation to get the dvice of an EXPERT to design the magnetizing fixture because that way he will save time and money (as long as he is consulting with the right peson.) And this will not be cheap either. Also, it does not assure that it will work out the first time.

As engineers we all know that what we design in paper and the final product rarely are the same (well, depending on the appication). The design is the road map to the design and construction, then comes the testing and continous experimentation to optimize the performance. To design and build a mg. zapper that will work YOU WILL HAVE TO SPEMD 100's if not 1000's of hours untill you get it right.

We are using some sophisticated methods to test the actual magnet saturation using FEA (Finite Element Analysis), which is the closest way to tell what is happening to the magnet and come to an accurate conclusion that it is being COMPLETELY SATURATED.
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Old 05-18-2006, 06:40 AM   #56
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As I`m wondering about this ...

Isn`t just soo that the magnetic field produced by the zapper needs to be as big as possible ???? well, if its big enough, it doesn`t have to be any bigger but if it`t twice as big it won`t harm the process, or will it ???


I mean, its never to strong ...... in my opinion .....

or can somone explain to me wy it could be tyo strong .. ????
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Old 05-18-2006, 11:20 AM   #57
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You cannot OVER magnetize a magnet.

But there is a point of no return.
Magnets are just like a glass of water you can fill it up to 100%, but anything more and it just spills over.
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Old 05-18-2006, 11:39 AM   #58
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Since we have the magentic gurus on the line I got a question... Is there the possibility to have north and south magentic poles with the possibility to either make one pole stronger than the other? Cancell out the opposite pole because there was either a seperation between the magnets and the fields were so close to each other? Move the concentration of the pole, thus magnetically changing the timing of the motor... I know that this has been tried, I witnessed it, but may have been done incorrectly, and with inferior equipment...

thanks.
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Old 05-18-2006, 12:40 PM   #59
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i THINK i BRUISED MY BRAIN READING ALL OF THIS...... Good info though.
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Old 05-18-2006, 01:32 PM   #60
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Quote:
Originally Posted by Mrshells
and theres only 2 things smell like fish and one of them is fish !!!
Yer the other is a CO27 ive decided

(personal joke people, dont pay any attention)
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