Solutions For High Current Draw

[hypergear]

As some of yous already knew that we are developing electric turbochargers. (lol don't laugh)

The prototype produces 3.3 psi of boost with 0RPMs of lag on a Rb25det engine with turbocharger disconnected.

How ever the motor that I'm using draws a large amount of current. it is hooked to an spare $500 Optima 12V battery that keeps it activated on 100% throttle for 15mints (obviously a normal person would not flog their car on full throttle for 15 mints straight on road).

The motor uses 12V DC, 120amps, and up to a maximum of 2400 watts.

If I am going to hook it up to the car battery or run the 2nd battery in parallel, is there a way that I can satisfy motor's draw current without affecting car's electrical instruments?

Ie. Capacitors or some thing in similar, or couple of capacitors, or more batteries in parallels connections, can the factory alternator charge all batteries in the parallel circuit through normal driving? Please post up your ideas. Thanks.

[Carbon 34]

As some of yous already knew that we are developing electric turbochargers. (lol don't laugh)

The prototype produces 3.3 psi of boost with 0RPMs of lag on a Rb25det engine with turbocharger disconnected.

How ever the motor that I'm using draws a large amount of current. it is hooked to an spare $500 Optima 12V battery that keeps it activated on 100% throttle for 15mints (obviously a normal person would not flog their car on full throttle for 15 mints straight on road).

The motor uses 12V DC, 120amps, and up to a maximum of 2400 watts.

If I am going to hook it up to the car battery or run the 2nd battery in parallel, is there a way that I can satisfy motor's draw current without affecting car's electrical instruments?

Ie. Capacitors or some thing in similar, or couple of capacitors, or more batteries in parallels connections, can the factory alternator charge all batteries in the parallel circuit through normal driving? Please post up your ideas. Thanks.

Yes lol

Ok the factory alternator is 80amps max and is fused at that level even high km still test close to 80 from the ones I've checked

Upgrade charge wiire to 4 Ga

Ground the alternator frame / bracket bolt 4ga

which optimia red/ yellow/ blue ?

Yellow is best choice

You can run a pair in partallel if purchased same time , same specs and test internal Resitance is close as possible

Without a charging diode breakout , optima arent the most powerful around but still a great battery

its late now but let me layout some ideas for you and crunch some numbers

its very doable without a major drama but i can get close to exact expectations

Options

Big main battery

Twin smaller but higher load batteries

Main battery with batcap

Isolated twin batteries like 4x4 uses or huge stereos

Li ion battery

High output alternator $$$$

or a better electric motor spec

Happy to help ya

[Carbon 34]

Well

Your motor has the wrong specs For 100% efficient which its not ?

If it runs 2400w max @12v that = 200amps

At 12v and 120amps max = 1440w max

Could it be a 12v/24v motor by chance ?

One of the ratings is wrong

What duty cycle do you think you would run max current draw for a min or two? most electric motors have a max duty cycle in specs ?? Your going to have to cool it somehow or it wont survive long??

Forget the physics law name but you cant produce enough power to be 100% efficient to run another device.... your battery operated motor will consume more power from the petrol motor to get the current to run the electric motor so the gain is minimal kw unless you use the electric motor that swaps to normal turbo at 3000rpm ?

To have no lag and useable boost

Or NA car looking for a cheap min mod for extra power ?

another way is use a system like kers on F1 car that stores wasted energy ? You could make one off the driveshaft using alternator or even generator and use ac or dc motor ??

that runs independent of the cars electical system

diode isolated but could be backed up by car battery in the case of no waste energy stored like on first start it wouldnt have lots of available current ?

But without more info i could only get you into a reliable solution to run 120amps even on a 80amp alternator short term

Figure 60amps to run the car on rainy cold night ?

Or hot rainy night ? with minimal buffer of course LED lights etc all help

-----------

I pull 7000watts max @12v but its for 30seconds in car audio , i use one smallish but extremely powerful battery and some trickery lol To provide that kinda power to the boot

On 80 amp alternator

And 100,000watt car audio systems exist but they operate in 16v and 4 or more alternators and a boot load of batteries Or high output mobile welding alternators 300amps plus

Anything is possible depends on your goal and specs and of course $$$$

[hypergear]

I've Listed the wrong motor. lol.

By specification on user manual it is:

-Max. Current: 130A

-Max. Voltage: 12V

-Max. Power: 1700W

It has a 12V cooling fan and heat shield attached to it.

This electric turbo won't be running at full capacity all times, Its configured to run 100% only when throttle is at 100%, or the compressor starts to surge. In a manual car assume I'm flogging it, the time cycle between each full throttle runs are less then 10 secs before I have to release throttle and change gears. The motor is powered down when throttle is released.

Do you think a capacitor is suitable for some thing in that setup? Providing sudden discharge of 10 secs and revive it self when motor stops drawing current.

Any diagrams that you post up and show the best setup in your mind? in both bugget and not.

Cheers.

[Carbon 34]

Lol thought so

Which colour battery are you using ? And the size ? Or model pleas

[hypergear]

Its currently a Optima Yellow top D31A.

[beenowened]

A capacitior may not be suitable as they dont discharge a constant current. After the first 1/5 of the time it takes to fully discharge the output current will only be about 30% of what it was intially. So to have a capactior that will discharge a current that high for around 10 seconds will have to be massive or have a lot of capacitors that may not be practical.

[Carbon 34]

Its currently a Optima Yellow top D31A.

Really that model is a bit large for a skyline case wise ? I take it the case is light grey not dark grey?

What application is that electric motor from ? That much current sounds like it would be slow to spool up as well? Scooter or golfcart motor?

How many rpm and hp does it produce ? Sounds like a lot of hp not a lot of rpm ? in my head I would think its not the right motor for the application and overkill industrial size

A turbo spins fast and even a dremel motor wouldnt spin that fast about half the max turbo speed ?

Does the motor spin on power always ? or disengage at xboost or rpm ? like a a/c clutch setup?

I would doubt the motor use's max current draw once running on a turbine load ? have you tested it with a amp clampmeter underload? free spinning it prob uses a quarter of the current ?

Your setup would work except on short drives or bad weather days where alternator power wouldnt recharge the battery enough it would short charge often and fail in half the time of normal

A few other little glitches

the upgrades would include all main wiring to starter and charging curcuits to fusebox and of course the electric motor is borderline at 4ga wire it could overheat and catch fire 150amps max on the best 4ga wire in normal heat 23c ?

underbonnet on a hot day you could be pushing beyond the limit on the wire even at 130amps , depends how long the run is and if the wire is in cool area or next to a smoking hot turbo ?

Your going to need a resetable breaker , 20 bucks a fuse works but that size fuse gets expensive if it triggers a dozen times during testing or on roadside a button push beats trying to find AGL or mini AGL fuses in whoop whoop

Does the motor use a trigger to turn on or is just on or off all the time ? a fused relay for that

A capacitor of 2 farad (2000watt) would buffer the start but it puts a load on the alternator as well recharge making matters worse not recommended

in electric motors the cap is for a start current jump is all , in car audio a cap recharges the coil and transistors during hi current transients in the music . A lot different application then yours

If any cap was used a smaller one depending on a lot of factors / specs in motor itself ? Some have caps built in ??? the motor has to be electronically isolated so the electronic noise doesnt enter the factory ecu , knock sensors, and car radio it could wreak havoc if its noisy electronic ripple? Not a big deal to solve in most cases

If you dont want this public you can pm me nondisclosure agreement to protect your interest and i could see exactly what your trying to do ? have extensive fab and engineering skills

I see your idea kinda a no lag device ? but I ponder your exact setup might be going down a path of using off the shelf motor that doesnt suite

The idea except on a lab bench ?

Edited August 6, 2012 by Carbon 34

[Carbon 34]

A capacitior may not be suitable as they dont discharge a constant current. After the first 1/5 of the time it takes to fully discharge the output current will only be about 30% of what it was intially. So to have a capactior that will discharge a current that high for around 10 seconds will have to be massive or have a lot of capacitors that may not be practical.

Agree to above , unless a small cap is needed to jump start the spin of a high torque motor , most of those have built in caps already for that reason

But it loads the alternator up making matters worse

Edited August 6, 2012 by Carbon 34