Cats & cars - EE question

[lolito_fr]

I'm getting pretty pissed off with some nocturnal animal leaving dirty paw marks, fur, and scratches in my paintwork, and am now looking into solutions...preferably involving high voltage

Question: how many volts would be needed to get a nice charge to jump through the paintwork and give said creature a decent jolt?*

Have tried 230 mains - not enough volts
Have tried an electric fly swat, not enough amps.
I have a plentiful supply of small power transformers lying around, which possibly could be coaxed into working in a step-up config...?

Other ideas?

*"the more the better" is not an acceptable answer - am not looking to kill anything/anyone - not just yet, anyhow

[miladiou]

je suis pas sur que les americains soient prets pour ce genre d'etude...

[jaydee]

You would probably get thrown in jail for years if you tried that here in the USA. We just use car covers if needed. Good luck though.

Also 230volts is plenty, what you need is amps. Hell 12 volt would be plenty if you have enough amps.

[DrMemory]

Originally Posted by jaydee116

You would probably get thrown in jail for years if you tried that here in the USA. We just use car covers if needed. Good luck though.

Also 230volts is plenty, what you need is amps. Hell 12 volt would be plenty if you have enough amps.

No 12 volts is not even close to enough, not even with a metal surface. And just like humans, if you put more than 10 - 100 uA across its heart you will KILL it. If you put several amps through some other body part you will FRY it (literally). Most Tasers work with 20 - 50 KV or more at > 1uA (carefully controlled) using metal pointed probes (to penetrate the skin) and no paint. It would take quite a bit more to get through the paint. I'm not sure you want this kind of voltage on your PC case. And PC cases are normally AC grounded through the PSU so I'm not sure how youd get the voltage on the PC case. Maybe you should find some other method?

[KnightElite]

He wants it for his car, not his PC case .

[Groth]

Where's your current return? If the car is electrified, can you convince the critter to carry a ground wire? And any voltage strong enough to conduct through the paint will also damage the paint.

Take advantage of the tendency of cats to lick their paws, dust your car with cayenne pepper.

[lolito_fr]

cayenne pepper. chuckle.

What happens when you get a static discharge? That goes through the paint, no? Doubtful it does any damage though :shrug:

[Groth]

Static charges are a surface phenomenon. And you'll only get an interesting discharge if that surface is at least a little conductive.

Localized heating can easily burn holes in a 'non-conductor' when it is pushed to dielectric breakdown. The damage can be big or small, but it will be there.

[killernoodle]

Here is an idea: Put catnip in a place where you want the cat to walk. Spray the cat with water if it jumps on the ride.

[DrMemory]

Originally Posted by KnightElite

He wants it for his car, not his PC case .

In that case he's definitely got a problem with too little ground instead of too much.

[jaydee]

Originally Posted by DrMemory

No 12 volts is not even close to enough, not even with a metal surface. And just like humans, if you put more than 10 - 100 uA across its heart you will KILL it. If you put several amps through some other body part you will FRY it (literally). Most Tasers work with 20 - 50 KV or more at > 1uA (carefully controlled) using metal pointed probes (to penetrate the skin) and no paint. It would take quite a bit more to get through the paint. I'm not sure you want this kind of voltage on your PC case. And PC cases are normally AC grounded through the PSU so I'm not sure how youd get the voltage on the PC case. Maybe you should find some other method?

12V @ 600amp is enough to make a cat jump.

[Etacovda]

lol, thats enough to make a cat burger

Use a cover, man - its safer, and probably cheaper, and it will protect your car from the elements too.

[greenman100]

Originally Posted by jaydee116

12V @ 600amp is enough to make a cat jump.

no. jaydee

you bash others for misinformation, but no qualms about spreading it yourself



shall I go hold a cat on the terminals?

[greenman100]

Originally Posted by Etacovda

lol, thats enough to make a cat burger

Use a cover, man - its safer, and probably cheaper, and it will protect your car from the elements too.

same to you, bud

goes for the review sites AND you

and expert on nuclear fission is not an expert on agriculture, by any means

and generally, articles about agriculture aren't written by nuclear physicists.

don't talk if you have no clue what you're talking about

[Etacovda]

Actually, if you could get 600A through the cat @ 12v , it WOULD fry it. Nothing was ever said about if the load was applied or not. Get 600A through a cat, and see what happens.

However, the resistance of the cat is too high to allow that (lol)

Take a wire and place it on both battery terminals and see what happens when a lack of resistance is applied. Come on, this is theory - its not as if hes actually going to fry a cat with it (is he?)

50mA stops a heart beating.

Take a ****ing chill pill, Tim; not my fault you're obviously having a bad day, bud.

[satanicoo]

greenman is right - no 12 volts can kill any animal.
I think the lowest is 24 volts, and they can kill only a cow. Depends on the animal.

Anyway, those electric fly-killers, i dont think they can be deadly to cats, and sure enought will scare them.

[Kobuchi]

Use a zinc paint on your car. This paint can be had in up to 90% zinc concentration. Obviously it conducts electricity pretty well, and as a bonus protects the underlying steel. It'll look so horrible you won't even notice the carbon marks left by passing cats.

[lolito_fr]

Ok, maybe a cover is the best idea...


...make it an alu. coated one though-

gotta have revenge, dammit

[Groth]

Maybe rig up a motion detector to a relay controlling a selenoid valve that turns a garden hose on/off. Anything gets near the car, it gets sprayed.

Just remember to shut it off before heading out.

[lolito_fr]

Groth, funny but both your suggestions I have seen somewhere before...
have you been having the same kind of problems!?

Currently trying the "Piment de Cayenne - Extra Fort" - yeah baby, eat that

[Groth]

I have squirrels, not cats. For some reason they like to chew the cedar trim around the door and windows. Every spring and fall I sprinkle a load of cayenne on the yard and under the trees/bushes to keep them away.

[greenman100]

Originally Posted by Etacovda

Actually, if you could get 600A through the cat @ 12v , it WOULD fry it. Nothing was ever said about if the load was applied or not. Get 600A through a cat, and see what happens.

However, the resistance of the cat is too high to allow that (lol)

Take a wire and place it on both battery terminals and see what happens when a lack of resistance is applied. Come on, this is theory - its not as if hes actually going to fry a cat with it (is he?)

50mA stops a heart beating.

Take a ****ing chill pill, Tim; not my fault you're obviously having a bad day, bud.

Actually it wasn't a bad day at all

it's just a little taste of procooling

interesting to see what it's like in front of the flame thrower, eh?

you won't get 600A through a live cat at 12v, ever

that is all

[DrMemory]

Originally Posted by jaydee116

12V @ 600amp is enough to make a cat jump.

Not it's not. The resitance of the cats body will keep current flow at VERY low levels (it's called Ohms law, you need to study it). So low that it will not feel it at all. It's the main reason cars use 12V batteries (electric cars use much higher, and truely dangerous battery voltages). It takes a skin puncture (or direct connection to a wet tongue) to lower the body resistance enough to feel it. Even then you will not be able to pass 600 amps through it.

[Etacovda]

Originally Posted by greenman100

Actually it wasn't a bad day at all

it's just a little taste of procooling

interesting to see what it's like in front of the flame thrower, eh?

you won't get 600A through a live cat at 12v, ever

that is all

Yes, but unlike the people that we rip the sh!t out of here, I DO realise what i said was 'wrong' technically but if the discussion was what i deemed to be 'serious' i wouldnt have said it. I thought it was evident that I knew basic physics, I guess not. (and yes, i have heard of ohms law...)


At least, I hope he isnt serious enough to do it (I have two cats, that would be damn cruel)

Wonder what the resistance of your average cat is though

[DrMemory]

Originally Posted by Etacovda

Yes, but unlike the people that we rip the sh!t out of here, I DO realise what i said was 'wrong' technically but if the discussion was what i deemed to be 'serious' i wouldnt have said it. I thought it was evident that I knew basic physics, I guess not. (and yes, i have heard of ohms law...)


At least, I hope he isnt serious enough to do it (I have two cats, that would be damn cruel)

Wonder what the resistance of your average cat is though

Levity and electricity are not good companions. Someone or something could get seriously killed.

Strange, I wondered the same thing as I was writing.