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Indiana
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I have 2 power supplies, 1 is 24v-50a and the other is 48v-25a. I would like to make these both adjustable from 0 up to their full v/a, so they can be used with some lasers and charging. I would like to use a touch screen arduino to adjust and view the volts, amps, watts and temp. I would settle for an lcd with knobs if I have to. Also I would like to turn the 48v into 4-12v adjustable power supplies and the 24v I would like to make so it can be used as 24v or 12. I have very good mechanical skills and tinker with all kinds of stuff, but electronics is something I usually dont mess with. I can do quite a bit with 12v stuff, I have a bunch of real r/c items and have batteries up to 22v. I basically want to turn these into fully adjustable lab power supplies, mounted inside an old computer case or an aluminum enclosure I will make. I will add some extra cooling inside as well. It would be cool to add 1 high voltage hookup like one for a neon sign, to run a tea laser off of if possible.

If there is anyone who can help me I would greatly appreciate it.


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Left Coast, CA (USA)
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While what you propose is possible it would take a very experienced power supply designer to actual accomplish it. You are talking very high maximum current values for those supplies requiring very large heatsinks and forced air cooling if using linear adjustable regulator circuits or very sophisticated adjustable switching regulators.

Take for instance that 24vdc 50 amp supply, if you wanted to be able to adjust the output voltage down to 1 volt but maintain a 50 amp output current capability, that would mean 23 X 50 = 1,150 watts of heat removal has to be managed, not an easy task even for a very experienced power supply designer. That's as much heat as a toaster generates.

So my advice is that unless you can find a already designed circuit and construction project that would work at your voltage and current levels of those two DC supplies, I would say your chances of success range from 0 to .01%. No offence meant, but sometimes you need some knowledge and experience to even know when something is very difficult or completely impractical to accomplish.

Lefty

 
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Indiana
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I have the 2 power supplies already, I just want to come off the power leads and divide, step down and make adjustable with Arduino.
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Left Coast, CA (USA)
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I have the 2 power supplies already, I just want to come off the power leads and divide, step down and make adjustable with Arduino.

I know that, and everything I wrote earlier applies. You have two filtered constant output voltage DC supplies and you require variable voltage regulation for their outputs, under control of an arduino. Check. How would you propose to 'divide' the output voltages?

Lefty

« Last Edit: February 06, 2012, 11:32:22 am by retrolefty » Logged

Indiana
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I dont know, thats why I am here asking. I do know I will get it figured out though, I always accomplish what I set out to do! smiley-wink
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I dont know, thats why I am here asking. I do know I will get it figured out though, I always accomplish what I set out to do! smiley-wink

Good luck. However I don't think you will get any more practical advice here then what I have already given you. Anyone else here have a solution for wby300?

Lefty
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At times enthusiasm and the will to succeed just isn't enough.
One has to also face the realities of life
With neither knowledge nor high energy circuit design skills, your best bet is to sell the two supplies and buy ones that meet your specific needs. 
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Maybe look into one of these as a ready made regulator:
http://www.synqor.com/Datasheets/NQ40x40HGx60_Datasheet.pdf

• High efficiency, 95% at full rated load current
• Delivers up to 60A of output current
• Input Voltage Range: 9-40 Vdc
• Output Voltage Range: 0 - 40V (negative output is possible)
• Extensive on-board input and output filtering
• No minimum load requirement means no preload resistors required
• Buck or buck-boost versions available
• Adjustable current limit with current monitor (F option)
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That seems to be the dogs bo**ocks. Any idea how much and where they can be bought.
Getting 60amps through those small pins might be a bit optimistic.
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Company contact info is on the last page of the datasheet. I would say contact them (email provided) if you want to buy one. I could not find any prices on their website... It's probably rather pricey. If you find out the price, let us know smiley-money
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Hi there,

I just started a rover robot and have an Arduino Uno hooked up to a 28BYJ48 stepping DC motor. I have code that should run it. When I upload the sketch and hold the motor, I can feel the potentiometer controlling the speed of its vibration but it isn't actually turning the output of the motor. Is this a problem with using the arduino uno's 5V "power" pin? What's a reasonable solution within a student's budget?

Thanks in advance for all your help,

Victor
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Indiana
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I guess I will have to get advice from some electricians first, I dont think putting 4 step downs on a line and making them adjustable is going to be anywhere as hard as you guys make it sound. When I get ready to snap some prefabbed parts together I will ask again. Vasalmon, You might want to start your own thread, asking a totally different question in someone elses thread isnt going to get you any answers.
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