Can you jump a car with a Computer power supply?

[dxkj]

Im not good with electrical terms, etc so I dont know, my friend asked me last night when his car was dead.

 

[Dufman]

i dont think a power supply has enough amp/volts/watts to jump a car.

 

[Shaftatplanetquake]

nah dude.

Assuming the battery is just dead from leaving on headlights..... It might actually be enough to slowly charge the battery and eventually get enough juice in it to crank...-- but its not going to jump it.

Jumping pulls a lot of power in a short amount of time, thats why jumper cables are so thick.

 

[hevnsnt]

lol.. GEEK!

 

[FoBoT]

no

the starter in your car is a series DC motor

the amount of current required to turn that motor/your engine is HUGE compared to what a computer pwr supply puts out

not even in the same ballpark

 

[Soybomb]

Not even close.

 

[Evadman]

A computer powersupply puts out 12v. your car is 12.6 nominal, but some can run with as little as 9.6v.

You may be able to charge it enough to get it to 12v or so, but you would need a current limiting device installed or you would be trying to pull 100-200 amps through the pws which will fry it in about a quarter of a second. basicly, you would be truckle charging it. Go to sears and spend $50 on a car charger/jumper set. hell, your pws is probably in the $100 range, and you can probably get a 2/10/150 charger/jumper for $100.

Or just go to kmart and buy the cheapest battery you can find and use that. They are like $29 for the cheaper than dirt ones.

In other words:
Computer psu = 20a max or so on the 12v line.
Starter motor = 200-500a on the 12v line.
which means computer supply = melted.

 

[FoBoT]

good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

 

[dquan97]

try it!

 

[Evadman]

Originally posted by: FoBoT
good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

if you do buy it and just want it for jumping, make sure to put it on a charger every once and a while, and do not put it drecltly on a concrete floor. it will actually discharge right throught he bottom of the battery. I have heard quite a few reasons for this, but they all sound like bull. but if you put a battery on a concreete floor it will die within a few days if not overnight.

 

[dxkj]

Woo, So i was somewhat right.


I told my friend there was probably only 18 amps on the 12v rail and that it would take a lot more than that to jump

 

[KeyserSoze]

Originally posted by: hevnsnt
lol.. GEEK!

That's what I was thinking. But I love these kind of threads. It's nice when you can try to sort of "rig" something to work, and often opens the door to new ideas. I dunno, I guess I'm just trying to say: Geeks, keep doing what your doing.



KeyserSoze

 

[PsychoAndy]

Originally posted by: Evadman

Originally posted by: FoBoT
good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

if you do buy it and just want it for jumping, make sure to put it on a charger every once and a while, and do not put it drecltly on a concrete floor. it will actually discharge right throught he bottom of the battery. I have heard quite a few reasons for this, but they all sound like bull. but if you put a battery on a concreete floor it will die within a few days if not overnight.

This is officially my pick for "Useless Information of the Day". I'll have to notate it into my Vat of Useless Know

 

You'll have a better chance with this

 

[etech]

Originally posted by: Evadman

Originally posted by: FoBoT
good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

if you do buy it and just want it for jumping, make sure to put it on a charger every once and a while, and do not put it drecltly on a concrete floor. it will actually discharge right throught he bottom of the battery. I have heard quite a few reasons for this, but they all sound like bull. but if you put a battery on a concreete floor it will die within a few days if not overnight.

?Will a battery be damaged or mysteriously discharged by allowing it to sit on concrete??
"Well, is it true? Will a battery be damaged or discharged by letting it sit on concrete? NO!"

 

Batteries can be damaged by concrete floors, so bad in fact that they cannot be recharged and must be discarded.

Drop one from 5 feet and find out.

 

[Eli]

I bet you could do it, but the car had better start real fast, cause I don't think the power supply would last.. lol

maybe wire it for 17V to cut down on the amps required.. prolly not recommended in a modern computerized car curious, if you wire it for 17v, does the max amps become the sum of the +12v and +5v rails?

I used to have a 12v, 6amp battery charger.. with a little ammeter on the front.. that would start our old little Dodge Colt(was having charging system problems with it for a while) as long as it started in the 2-3 seconds the charger could put out all 6 amps before the safety switch went "clunk".

It was my general 12v power supply... at least, that's what I used it for.. until I drew more than 6 amps one too many times.. Actually, I think it got left with the leads shorted for a couple of days.. lol

 

[Bignate603]

Originally posted by: etech

Originally posted by: Evadman

Originally posted by: FoBoT
good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

if you do buy it and just want it for jumping, make sure to put it on a charger every once and a while, and do not put it drecltly on a concrete floor. it will actually discharge right throught he bottom of the battery. I have heard quite a few reasons for this, but they all sound like bull. but if you put a battery on a concreete floor it will die within a few days if not overnight.

?Will a battery be damaged or mysteriously discharged by allowing it to sit on concrete??
"Well, is it true? Will a battery be damaged or discharged by letting it sit on concrete? NO!"

Interesting read...

 

[Eli]

Originally posted by: Bignate603

Originally posted by: etech

Originally posted by: Evadman

Originally posted by: FoBoT
good point on a new battery being a cheap solution, a $30 one will probably last you 3 years or more anyway

if you do buy it and just want it for jumping, make sure to put it on a charger every once and a while, and do not put it drecltly on a concrete floor. it will actually discharge right throught he bottom of the battery. I have heard quite a few reasons for this, but they all sound like bull. but if you put a battery on a concreete floor it will die within a few days if not overnight.

?Will a battery be damaged or mysteriously discharged by allowing it to sit on concrete??
"Well, is it true? Will a battery be damaged or discharged by letting it sit on concrete? NO!"

Interesting read...

Indeed..

 

[xirtam]

?Will a battery be damaged or mysteriously discharged by allowing it to sit on concrete??
"Well, is it true? Will a battery be damaged or discharged by letting it sit on concrete? NO!"

But from the article:

The fact is, all batteries self- discharge whether they?re sitting on the shelf or on concrete.

So the answer is "yes."

 

[Zenmervolt]

Originally posted by: xirtam

?Will a battery be damaged or mysteriously discharged by allowing it to sit on concrete??
"Well, is it true? Will a battery be damaged or discharged by letting it sit on concrete? NO!"

But from the article:

The fact is, all batteries self- discharge whether they?re sitting on the shelf or on concrete.

So the answer is "yes."

Uh, the answer is no. Yes a battery sitting without use will discharge regardless. However, putting the battery on concrete will cause anything abnormal to happen. There was a myth at one point that putting a battery on concrete will discharge it faster than anything else, which is simply not true.

ZV

 

[d33pt]

that myth used to be true at one point..in the 60's or something.. that's why old people like to pass it on

 

[rudeguy]

Jumping pulls a lot of power in a short amount of time, thats why jumper cables are so thick.

true...but I have jumped a car using 14 guage speaker wire