What gauge or wire is needed for 24V at 600amps?
09-01-2004, 11:59 AM
#1
Registered User
Thread Starter
What gauge or wire is needed for 24V at 600amps?
I hadn't heard of this before, but some company has come up with a nitrous alternative - using short bursts of an electrically power supercharger. It uses a seperate battery system, hence the short burst limitation before the power is drained. Then over a period of minutes, the regular alternator can recharge that seperate system.
It uses two additional car batteries (hence the 24V rating) and uses three electric motors for a total of 18hp to produce about 5 to 7 psi of boost.
18hp is 13.42kW. At 24V, that's 559 amps of electricity. Any electricians out there care to comment about how feasable it is to pump that many electrons around?
It uses two additional car batteries (hence the 24V rating) and uses three electric motors for a total of 18hp to produce about 5 to 7 psi of boost.
18hp is 13.42kW. At 24V, that's 559 amps of electricity. Any electricians out there care to comment about how feasable it is to pump that many electrons around?
09-01-2004, 12:55 PM
#2
I would expect that the motor would pull even more current than that due to inefficiency. It would take a pretty damn large cable to keep the voltage from dropping accross the cable. Acording to my charts, it would take a cable LARGER than a 750 MCM, which is over 1" in diameter.
09-01-2004, 01:03 PM
#3
Registered User
Join Date: Jan 2004
Location: SF, California
Posts: 3,759
Likes: 0
Received 0 Likes
on
0 Posts
I assume you're referring to this?
https://www.s2ki.com/forums/index.php?showtopic=186847
potentially interesting idea...curious now to see what the kit contains....
https://www.s2ki.com/forums/index.php?showtopic=186847
potentially interesting idea...curious now to see what the kit contains....
09-01-2004, 01:30 PM
#4
Registered User
Thread Starter
Yep, that's the one. Initially I was thinking about it in a general "How much electricity is needed for 20hp - about 15kW - at 12 volts?" point of view. Then during research today I heard about the Thomas Knight product. Sorry, didn't see the other thread. 
At the same time, I've read that 80hp of parasitic loss is in the ballpark for a supercharger at 15psi. That's nearly 4000 amps of electricity at 12 volts!
At the same time, I've read that 80hp of parasitic loss is in the ballpark for a supercharger at 15psi. That's nearly 4000 amps of electricity at 12 volts!
09-01-2004, 03:08 PM
#5
Join Date: Oct 2000
Location: 12m SW of Glen Rose, Tx
Posts: 986
Likes: 0
Received 10 Likes
on
7 Posts
Originally Posted by Elistan,Sep 1 2004, 02:59 PM
I hadn't heard of this before, but some company has come up with a nitrous alternative - using short bursts of an electrically power supercharger. It uses a seperate battery system, hence the short burst limitation before the power is drained. Then over a period of minutes, the regular alternator can recharge that seperate system.
It uses two additional car batteries (hence the 24V rating) and uses three electric motors for a total of 18hp to produce about 5 to 7 psi of boost.
18hp is 13.42kW. At 24V, that's 559 amps of electricity. Any electricians out there care to comment about how feasable it is to pump that many electrons around?
It uses two additional car batteries (hence the 24V rating) and uses three electric motors for a total of 18hp to produce about 5 to 7 psi of boost.
18hp is 13.42kW. At 24V, that's 559 amps of electricity. Any electricians out there care to comment about how feasable it is to pump that many electrons around?
09-01-2004, 08:35 PM
#7
Registered User
I think you will find what everyone else is- factor in the alternator load, or the extra battery drain... and you will find that your HP isn't as "free" as you thought. That's why people always go back to turbo and SC for FI.
FWIW, the factors in cabling are current draw, voltage, length, and time. The voltage is important since you will drop voltage over distance. That is a fixed value based on current and length... hence a 120V system is more tolerant of voltage drop compared to a 12V system (unless you have some adaptive load or regulation). Time is important if you are pushing the limits to avoid mechanical damage of the conductor (overheating). You can draw thousands of amps through a tiny conductor if it's for <1s. I am not sure what the load looks like for the system but I am certain it's longer than that.
To safely conduct 600A from, say, 12ft away (electrically) in the trunk, you will need a bundle of probably 6 4AWG wires. 1 4AWG can safely conduct 100A over that distance with very little voltage drop. You could concievably draw less.
Save the math excercise and just call me about a turbo kit. I can give you more power, more reliably.
FWIW, the factors in cabling are current draw, voltage, length, and time. The voltage is important since you will drop voltage over distance. That is a fixed value based on current and length... hence a 120V system is more tolerant of voltage drop compared to a 12V system (unless you have some adaptive load or regulation). Time is important if you are pushing the limits to avoid mechanical damage of the conductor (overheating). You can draw thousands of amps through a tiny conductor if it's for <1s. I am not sure what the load looks like for the system but I am certain it's longer than that.
To safely conduct 600A from, say, 12ft away (electrically) in the trunk, you will need a bundle of probably 6 4AWG wires. 1 4AWG can safely conduct 100A over that distance with very little voltage drop. You could concievably draw less.
Save the math excercise and just call me about a turbo kit. I can give you more power, more reliably.
Trending Topics
09-02-2004, 07:11 AM
#8
Registered User
Thread Starter
Gotta love that first law of thermodynamics, eh?
Gregg, I'm glad you mentioned hybrids. Given the law of conservation of energy, I've been thinking about where the energy for electric IMA comes from. I see two places - first, running the gas engine to drive a generator that recharges a battery. This isn't exactly free energy - through the various stages it goes through, there are quite a few losses, no? Wouldn't it be more efficient to simply use that chemical energy from the gasoline to instead drive the wheels directly? The second place is the regenerative braking - and this part IS free energy, since it would otherwise be dissipated as heat in the braking system.
My understanding is that the ONLY way that hybrids benefit is from the regenerative braking system. I've read that people get much better milage in city stop-go driving than constant highway driving.
(Unless, much like a deisel electric locomotive, the gas engine can be run at such a high state of efficiency that it overcomes the losses inherant in a chemical(gas)->electrical->chemical(battery)->electrical->mechanical engergy transformation.)
This year's Le Mans had two non-traditional race cars - one was a diesel, the other was some sort of bio fuel. It'd be neat to see a car equipped with a regenerative braking system...
Gregg, I'm glad you mentioned hybrids. Given the law of conservation of energy, I've been thinking about where the energy for electric IMA comes from. I see two places - first, running the gas engine to drive a generator that recharges a battery. This isn't exactly free energy - through the various stages it goes through, there are quite a few losses, no? Wouldn't it be more efficient to simply use that chemical energy from the gasoline to instead drive the wheels directly? The second place is the regenerative braking - and this part IS free energy, since it would otherwise be dissipated as heat in the braking system.
My understanding is that the ONLY way that hybrids benefit is from the regenerative braking system. I've read that people get much better milage in city stop-go driving than constant highway driving.
(Unless, much like a deisel electric locomotive, the gas engine can be run at such a high state of efficiency that it overcomes the losses inherant in a chemical(gas)->electrical->chemical(battery)->electrical->mechanical engergy transformation.)
This year's Le Mans had two non-traditional race cars - one was a diesel, the other was some sort of bio fuel. It'd be neat to see a car equipped with a regenerative braking system...
09-02-2004, 08:02 AM
#9
I don't see how it would be possible for any car (hybrid or not) to get better mileage out of stop and go driving. Regenerative braking is going to have its own losses. There will be loss converting electric enerty into mechanical energy, then there will be more losses converting that mechanical enerty back into electrical energy. When cruising on the highway, there is no conversion from mechanical to electrical, so those losses are avoided.
