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URGENT: High Current PSU help






You can search RC forums since they commonly use/modify these for their high power chargers and are quite successful. I would recommend looking at the ones with good reviews/lots of info regarding tweaking etc if you're not too technically inclined or not willing to trace the circuit to know how to tweak it.
 
Hey KRNAZNBOY, the real secret to obtaining those 100A or even 1000A of juice is to have large capacitors. Music is made up of waves, so it doesn't need to be pushing out 100A all the time. Let the capacitors in the amp handle those highs and lows as needed, you just need to make sure the amp is designed to provide enough peak current. Depending on your power supply, you can buy "car audio capacitors" for your audio system and hook them up as needed.
 
hey Just wondering if the amp is 350W "RMS" and where you got the 25% efficiency from? maybe you could tell us the amp model/make,
I would judge the current Usage on the fuse that is plugged into the amp, e.g 15A, 20A, 30A, or 2 X "xxA" Fuse etc, I cant Imagine that an Amp that Uses 100A would be weilding a 20A fuse to protect it if you know what i mean, also
The big fuses (80A + etc) are usually on the main cable about a foot away from your battery but the size of that fuse usually is dependant on the cable size,
anyway I would still stick with the Car Battery idea and some sort of charger, but dont rule out the idea of other power sources!
Im not 100% sure about any of the stuff i wrote above but its just what i seem to beleive... Good Luck!

Bionic-Badger said:
Hey KRNAZNBOY, the real secret to obtaining those 100A or even 1000A of juice is to have large capacitors. Music is made up of waves, so it doesn't need to be pushing out 100A all the time. Let the capacitors in the amp handle those highs and lows as needed, you just need to make sure the amp is designed to provide enough peak current. Depending on your power supply, you can buy "car audio capacitors" for your audio system and hook them up as needed.
Click to expand...
Yea a capacitor is good to future proof your setup for when you get a car, stops wrecking batteries, alternators and possibly other electronics on newer cars, and your headlights wont dimm everytime Your sub puts out a good BOOM too,
 
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RYDorDIE278 said:
hey Just wondering if the amp is 350W "RMS" and where you got the 25% efficiency from? maybe you could tell us the amp model/make,
I would judge the current Usage on the fuse that is plugged into the amp, e.g 15A, 20A, 30A, or 2 X "xxA" Fuse etc, I cant Imagine that an Amp that Uses 100A would be weilding a 20A fuse to protect it if you know what i mean, also
The big fuses (80A + etc) are usually on the main cable about a foot away from your battery but the size of that fuse usually is dependant on the cable size,
anyway I would still stick with the Car Battery idea and some sort of charger, but dont rule out the idea of other power sources!
Im not 100% sure about any of the stuff i wrote above but its just what i seem to beleive... Good Luck!

Yea a capacitor is good to future proof your setup for when you get a car, stops wrecking batteries, alternators and possibly other electronics on newer cars, and your headlights wont dimm everytime Your sub puts out a good BOOM too,
Click to expand...


+1 rep that makes so much fricking sense OH MAI GAD!

Cyparagon said:
I... don't think you and I agree on the definition of "urgent."
Click to expand...

You're probably right, it is urgent in the respect that i need this sorted out by the time my sub is built, or it will just be sitting around...
 
You still haven't answered my question that could help others point you to the right direction.

djQUAN said:
BTW, what car amp is that? I'm willing to bet that car amps today totally overspec their ratings so you will probably be able to use a lower current supply than you think.
Click to expand...
 
I am using a USA-made Crutchfield Sound Ordinance M-1350 amplifier, with 350watt RMS at 2 ohms impedence
 
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mono subwoofer amplifier
210 watts RMS x 1 at 4 ohms (350 watts RMS x 1 at 2 ohms)
variable low-pass filter (40-300 Hz, 12 dB/octave)
variable bass boost (0-12 dB, at 45 Hz)
variable subsonic filter (10-40 Hz)
PWM (pulse width modulation) power supply with MOSFET output
preamp inputs and outputs
fuse rating: 25A x 2
8-gauge power and ground leads recommended — wiring and hardware not included with amplifier
13-5/16"W x 2-1/8"H x 9-13/16"D
warranty: 3 years
Our 60-day money-back guarantee
Click to expand...

I don't think you'd need more than a 50A power supply for that.
 
Yep! I am supposed to use a 60 amp in-line fuse, so im good with just one of those power supplies!

Who knew the solution was only $18!!!!!!!!!!!

:beer:
-Matt
 
Dont forget you might have to do some modding of the power leads too, you might need to get all/some the 12V+ wires and connect them together then a fuse (as close to the power supply as possible) then possibly your recomended 8gauge to the Amp
Aswell as all/some the 12V- and connect them together then maybe 8gauge to Amp, and i would try keep both the +/- power leads as Short as possible from PSU to AMP

If you just run one 12V+ and one 12V- from PSU The wires might get a bit angry and possible some free heat and "other stuff" may happen
Just an idea anyway....
 
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An external fuse probably won't be necessary as the powersupply has extensive protection but it won't hurt anyway.

Mine wouldn't start up with a halogen headlamp as a load as these are basically a short circuit when cold even with long #16 wires which aren't that thick and should pretty much burn up at 57A.

If your amp's internal PSU doesn't have soft start, you may have trouble with the powersupply shutting down but you might get lucky. Let me know how it goes when you get it.
 
djQUAN said:
An external fuse probably won't be necessary as the powersupply has extensive protection but it won't hurt anyway.

Mine wouldn't start up with a halogen headlamp as a load as these are basically a short circuit when cold even with long #16 wires which aren't that thick and should pretty much burn up at 57A.

If your amp's internal PSU doesn't have soft start, you may have trouble with the powersupply shutting down but you might get lucky. Let me know how it goes when you get it.
Click to expand...

How can i avoid that? SOme sort of resistor as a load?
 
Nope. Unfortunately, the only way is just keep turning the supply on/off until the supply caps charge up and the powersupply stays on.

If the output voltage isn't cranked up too high, the powersupply protection isn't going to be touchy and won't false trigger a lot.
 
Guys, also, as iam not running this in a car YET, i need something to trip the REMOTE input on my amplifier, which would normally come from the Head unit in the car. I don't want to send 12v @ 75 amps to the remote pin, so could i just hook the REMOTE line to the 3.3v rail, or is that not enough voltage?

The REMOTE is kinda like TTL, but i don't know the specs...
 
It's a voltage operated high impedance input. It doesn't matter what the current capability of the power supply is. Just add a toggle switch between that and your 12V input. Or tie it to 12V directly.
 
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