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ArcticMyst Security by Avery

Capacitor

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Hello, I am quite new to electronics and I recently brought 20 - 320V 120uf Capacitors. The reason is I wanted to create a taser of somthing out of them, for fun. I am going to charge them with a disposable camera which has the same Capacitors and was wondering if there was any other way such as a transformer. Another question I have is there are many KV caps out there but they have around 100uf, does this meen that they hold less than my little ones and lastly, if I linked 2 330V together would it meen I have 660V

Thanks.
 





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A capacitor stores the energy that you put into it...
Its capacity (micofarads=uF) is a rating of it's capacitance.
Its Voltage rating is the Maximum voltage that can be
applied before failure...

You can charge a capacitor with regular batteries or
a DC Power Supply.....

Going over the rated voltage can cause the Capacitor
to explode...


Jerry
 
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ped

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^^ jerry is right.

But a taser only uses caps to dump energy into the primary of a step up pulse transformer which then generates many Kv at the output, without that transformer , you have a remote defibrilator.
 
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I have blown up some capacitors before, not fun...

But to shock someone you won't necessarily need the transformer. The capacitors themselves will give quite a bite. Unless you do want to incapacitate someone.

I would use the camera to charge them because you can still use the LED to know when they are fully charged.

And I don't know about connecting them.
 

ped

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The tasers are generally regarded as none lethal, but to give someone a a hit from a high uF fully charged cap, in the right place, could stop thier heart...the same way a defib restarts their hearts.
 
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Not only that... if the capacitor is large enough and the voltage is
high enough it will poke a hole through skin and could cause bleeding...
Dangerous stuff if you are not careful and have no electronic or
electrical knowledge...:eek:


Jerry
 
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If you put those 120uF 330WVDC capacitors in series you will get 60uF 660WVDC.
If you put them in parallel you would have 240uF 330WVDC.

Putting them in series effectively doubles the thickness of the insulator while the square area of the plates remains unchanged.

Putting them is parallel effectively doubles the square area of the plates while the thickness of the insulator remains unchanged.

The specs of the cap are related to the dielectric constant of the insulator and the square area of the plates. With higher dielectric strength insulators you can have a thinner insulator for a given voltage. The thinner the insulator for the same square area, the higher the capacitance.

Polarized capacitors can vent or explode if inserted into a DC circuit incorrectly or used in an A/C circuit.

This is a simplified explanation of what can be a fairly complex subject.
 
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ped

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^^ very good and absolutely correct.

If your not sure what your doing, you should leave well alone, or be very carefull.
 
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I just wanted to generate a spark realy, which would be the best way to do so(questionmark)
 
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Caps are always "live" unless properly discharged and checked with a meter. :)
 

HIMNL9

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Starting with scrap (mostly) parts, primary circuit of a disposable camera flash, that charge an 1uF 450V capacitor through a resistor (100 ohm 1W is enough), that then discharge the capacitor in the primary of a HV transformer through a simple gas-discharger 300/350V protector ..... this is the more easy way (if not for the fact that you probably need to wind yourself the HV transformer) ..... anyway, as HV transformer, can be enough to wind like 20 turns of 1mm dia paint-insulated wire as primary, on a ferrite rod, then insulate it very well (5 or 6 layers of large plastic adhesive tape are usually enough), then get some 0.1mm paint-insulated wire and start to wind the secondary ..... you need to be careful with this ..... like, 150 turns each layer, carefully winded without cross the wire, insulating each layer with the same tape, and making 4 or 6 layers, must give you enough voltage at the end for make some discrete sparks.

Or it can be done a bit better, but that require some more efforts ..... i've made so much ones in the past, that i've lost the count :p :D
 

BennyF

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If you put those 320uF 330WVDC capacitors in series you will get 160uF 660WVDC.
If you put them in parallel you would have 640uF 330WVDC.

Capacitance is the reverse of resistance when it comes to the math portion. In a parallel situation with a resistance circuit we would see a decrease in resistance and each would have the same applied voltage. In a series circuit with resistance our voltage would drop and our resistance would increase.

However with a capacitive circuit if we parallel the capacitors we would increase our capacitance and each would have the same applied voltage. In a series capacitive circuit we would see the voltage drop and our capacitance would drop. capacitors are connected in series to obtain a higher working voltage.

Series: 1/Ceq=1/C1+1/C2+1/C3...
Parallel: Ceq= C1+C2+C3...

and as for the taser here is a schematic i found that should give you what your looking for HERE.
 
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Utilizing large capacitances for a taser is very dangerous. A large capacitance when in contact with living flesh will equate to a large current unless the voltages are very low. Before you touch any high voltage capacitor(above 50v), as mentioned above, test with multimeter to ensure that it is discharged. If you need proof of the destructive capabilities of a photo flash or larger capacitor, put on some safety glasses and try taking a charged cap and touch the terminals to a piece of aluminum foil. Notice the loud discharge, the holes in the foil that are now vaporized aluminum. Hmm, metal instantly vaporized..... yeah, it would be a great idea to try this on something living...NOT.

Tasers utilize much higher voltages at very low current. As someone mentioned earlier high voltage + large capacitance = Defibrillator a device that can stop a human heart.

Those unfamiliar with high voltage and high current safety should not attempt to play with these types of circuits.

The soapbox is creaking under my weight, so I'll step down now.
 

BennyF

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I will agree with the others here that tasers are very dangerous and should only be used in self defense and not just to run around shocking your friends. just know that it takes .01A to cause your hart to fibrillate and can cause you to die. Now i know what you are thinking that that isn't very much and really it isn't and I know we all here work with amperage much higher then that and I'm sure the precautions are being taken to ensure that safety is key. You also need to know that it takes a voltage of 10,000 to jump an inch in nominal humidity (actually its about 3,000,000V per meter). So just use some common sense and know that these are very dangerous and should not be taken lightly. If you need more information on the science behind this please PM me I would be glad to help :)
 




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