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dryer wire

Posted: Wed May 05, 2010 2:00 pm
by bighead33
can i use these high voltage dryer wire for stun gun ignition. i mean i got a bunch of this stuff and i got to do some thing whith it :D
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Posted: Wed May 05, 2010 2:09 pm
by metalmeltr
You can try it, but that only operates at 240V and is probley only reted to about 600V.

Posted: Wed May 05, 2010 2:20 pm
by Mr.Sandman
You could use that if you are really desperate, but i would suggest some low resistance wiring.

Posted: Wed May 05, 2010 2:33 pm
by metalmeltr
Mr.Sandman wrote:You could use that if you are really desperate, but i would suggest some low resistance wiring.
You could use spark plug wires for stungun ignition.

Posted: Wed May 05, 2010 3:06 pm
by starman
Don't fool with this large gauge stuff. I would much sooner you use some standard solid core 22 gauge hookup wire with a couple of layers of heat shrink tubing shrunk down over it.

Many spark plug wires today aren't solid core metal and you'll find them very frustrating to work with. The other option will be HV wire used to supply anode voltage to old CRTs.

Posted: Wed May 05, 2010 3:44 pm
by bighead33
i looked for shrink tubing but all i cloud find were these either very small packets for making connections and these 6in one :? [/url]

Posted: Wed May 05, 2010 6:37 pm
by jimmy101
People always getting wiring stuff wrong.

1. You don't need "low resistance" wire. Any generic piece of copper wire has such a tiny resistance as to be functionally identical to zero.

2. The wire insulation is probably only rated to 600V or so but that really doesn't matter too much. The key is the breakdown voltage of the wire insulation plus the distance between the two wires is greater than the breakdown voltage of the spark gap(s). As long as the wire are kept separated by say at least a half inch then the insulation is fine. (Heck, with a 1/2" separation you don't need any insulation on the wire at all.) The wires should also be routed such that the gunners hands don't provide a short path. :shock:

3. Automotive ignition wire is just about the worst wire you could possibly use for an ignition system. (a) it is expensive and (b) it has very high resistance, typically 10,000 times more per foot than a generic piece of copper wire. Traditional spark plug wire doesn't even contain a wire, it has graphite impregnated string (or something similar) as the conductor. Besides, even traditional spark plug wire insulation won't withstand 30KV, which is why it was always routed and mounted so that it didn't touch any metal parts.

The wire in the OP is perfectly fine for an ignition system. If it is stranded then it is better than a single solid copper wire since it'll be much more flexible. And the colors are nice. :roll:

Posted: Wed May 05, 2010 6:37 pm
by jimmy101
People always getting wiring stuff wrong.

1. You don't need "low resistance" wire. Any generic piece of copper wire has such a tiny resistance as to be functionally identical to zero.

2. The wire insulation is probably only rated to 600V or so but that really doesn't matter too much. The key is the breakdown voltage of the wire insulation plus the distance between the two wires is greater than the breakdown voltage of the spark gap(s). As long as the wire are kept separated by say at least a half inch then the insulation is fine. (Heck, with a 1/2" separation you don't need any insulation on the wire at all.) The wires should also be routed such that the gunners hands don't provide a short path. :shock:

3. Automotive ignition wire is just about the worst wire you could possibly use for an ignition system. (a) it is expensive and (b) it has very high resistance, typically 10,000 times more per foot than a generic piece of copper wire. Traditional spark plug wire doesn't even contain a wire, it has graphite impregnated string (or something similar) as the conductor. Besides, even traditional spark plug wire insulation won't withstand 30KV, which is why it was always routed and mounted so that it didn't touch any metal parts.

The wire in the OP is perfectly fine for an ignition system. If it is stranded then it is better than a single solid copper wire since it'll be much more flexible. And the colors are nice. :roll:

Posted: Wed May 05, 2010 9:03 pm
by Technician1002
Some notes on wire from an electronics technician;

Ignition wire is made for - well ignition. So why is it not recommended?

The insulation is pretty good, but the reason for the standoff is not because the voltage will arc through it, but because to hold the high voltage, it has a fairly high dielectric constant, IE makes a capacitor. This is a trade off for high temperature operation as most low dielectric materials have low melting temperatures. The shunt capacitance robs power from the spark. The standoff's reduce this loss and prevent engine vibrations from wearing a hole in it.

The resistance of the wire is very true. It does limit the spark current. The reason for it is to limit the peak spark current so the capacitance and inductance of the wire does not make a spark gap transmitter (radio noise). For the occasional pop you make with spudguns, this is not required to meet FCC guidelines.

The carbon core is fragile and doesn't like much handeling and does burn over time in hot locations, so it does require replacement. It will work fine on a spudgun if it is kept short and not permitted to be flexed often and never stretched.

Hookup wire has fairly high dielectric constant so it is not an improvement over ignition wire in that regard. PVC will absorb some moisture and can break down in high voltage. Teflon or Nylon insulated wire is much better choices. Wire for BBQ igniters is an excellent choice. It tends to be high temperature and high voltage insulated as well as having a solid center conductor instead of a fiber core.

Another excellent source for the wire is from a neon sign shop. Wire used for neon signs works excellent, but is not as high temperature rated.

About the worst stuff to use is the clear PVC stuff they use for speakers. It absorbs moisture, breaks down releasing Chlorine which attacks the copper turning it to green goo or dust. Salt from you sweat makes this even worse. Never use the clear speaker wire for an ignition.

Posted: Wed May 05, 2010 10:21 pm
by bighead33
thanks Technician1002 & Jimmy101 you guys make it real clear :)

Posted: Sat May 08, 2010 11:47 am
by jimmy101
Technician1002 wrote: Ignition wire is made for - well ignition. So why is it not recommended?

The insulation is pretty good, but the reason for the standoff is not because the voltage will arc through it, but because to hold the high voltage, it has a fairly high dielectric constant, IE makes a capacitor. This is a trade off for high temperature operation as most low dielectric materials have low melting temperatures. The shunt capacitance robs power from the spark. The standoff's reduce this loss and prevent engine vibrations from wearing a hole in it.

The resistance of the wire is very true. It does limit the spark current. The reason for it is to limit the peak spark current so the capacitance and inductance of the wire does not make a spark gap transmitter (radio noise). For the occasional pop you make with spudguns, this is not required to meet FCC guidelines.
Traditional spark plug wire will indeed arc through if it is in contact with grounded metal. To prove it, just hold a wire while the engine is running while your other hand is in contact with a another piece of the car's grounded metal. In most cases you will get shocked. Spark plug wire is an integral component of traditional car spark systems and it does more than just move the EMF and current from one place to another. It is part of the balanced RLC spark system and provides most of the "R" during the spark phase of the ignition cycle.

Posted: Sat May 08, 2010 11:49 am
by jimmy101
Technician1002 wrote: Ignition wire is made for - well ignition. So why is it not recommended?

The insulation is pretty good, but the reason for the standoff is not because the voltage will arc through it, but because to hold the high voltage, it has a fairly high dielectric constant, IE makes a capacitor. This is a trade off for high temperature operation as most low dielectric materials have low melting temperatures. The shunt capacitance robs power from the spark. The standoff's reduce this loss and prevent engine vibrations from wearing a hole in it.

The resistance of the wire is very true. It does limit the spark current. The reason for it is to limit the peak spark current so the capacitance and inductance of the wire does not make a spark gap transmitter (radio noise). For the occasional pop you make with spudguns, this is not required to meet FCC guidelines.
Traditional spark plug wire will indeed arc through if it is in contact with grounded metal. To prove it, just hold a wire while the engine is running while your other hand is in contact with a another piece of the car's grounded metal. In most cases you will get shocked. Spark plug wire is an integral component of traditional car spark systems and it does more than just move the EMF and current from one place to another. It is part of the balanced RLC spark system and provides most of the "R" during the spark phase of the ignition cycle.

Posted: Sat May 08, 2010 1:36 pm
by Technician1002
jimmy101 wrote:
Traditional spark plug wire will indeed arc through if it is in contact with grounded metal. To prove it, just hold a wire while the engine is running while your other hand is in contact with a another piece of the car's grounded metal. In most cases you will get shocked. Spark plug wire is an integral component of traditional car spark systems and it does more than just move the EMF and current from one place to another. It is part of the balanced RLC spark system and provides most of the "R" during the spark phase of the ignition cycle.
Did you miss the part about the insulation is a dielectric? A low current discharge from the outside of the insulation due to dielectric coupling is rarely enough to short out the ignition. You may have noticed when you coupled some current off to get the shock, that most of the current is still indeed delivered to the spark plug. If the wire simply contained DC, then there would not be the AC current coupled through and this shock would cease to be there because the insulation is not conducting.

Even air couples AC voltages. A vacuum has a dielectric constant of one. Air is barely above that. Other common insulator dielectric properties are in this table. Your ignition wire insulation is in the list.

http://en.wikipedia.org/wiki/Relative_permittivity

It is in the group of electro-active polymers with a value somewhere between 2 and 12. This is NOT insulation failure. It does couple AC voltage through it. All insulators have this. Only a metal shield can remove this by grounding the current to low voltage. The current still flows.

Edit;
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This AC coupling of voltage is often used to trace cable. I have this test set that I use on a regular basis. The high impedance probe with a NON Conductive tip can still pick up the AC voltage in the wire and amplify it to trace a tone signal placed on the wire. There is no need to cut the insulation to listen to the signal in the wire. A shielded coax wire will ground the leakage and carry it off so a signal in a coax can't be sniffed, but if the signal is put on the shield, then the cable is fully traceable as the tone can be clearly heard outside the insulation on the shield.

http://www.byramlabs.com/product_info.p ... cing%20Kit

AC coupling of current onto the outside of a high voltage ignition wire is not conclusive proof that the insulation is failed.