Hello,
I got several programming/electrical/hardware questions for my project.
I have a project where I change magnets current to flip their poles. I've been able to do this with 2 magnets an Uno / SN75441 and a simple lab supply.
Now I want to make it a finished project with 10 magnets (electromagnets ofc: 12v at 0.25A).
I found a pc supply that has 12v+ and can pack 13 amp's
=> first question, how do I connect this properly, I had to jumper a connection to get it on (legit? see pic).
=> second question, Do I make a pcb for this or can I still work with a breadboard.
=> If I find the 12v+ cable out do I split it in to 5cable to power each magnet's driver or do I connect it to the pcb/breadboard and connect them via the pcb/breadboard.
=> How do I ground the arduino and the supply?
Coding questions will follow once I got the 10 setup to work.
pics will follow can't upload them for the moment
duplicate posts removed (did your enter key got stuck? 
robtillaart:
duplicate posts removed (did your enter key got stuck?
Very strange post indeed, pictures wouldn't upload and I might have tried several times not knowing the post had got through. Thanks for editing!
I had to jumper a connection to get it on
Yes that is how PC power supplies work.
second question, Do I make a pcb for this or can I still work with a breadboard.
Do not work with breadboard, it will not handle these sorts of currents. Either a PCB or something like strip board or perf board.
do I split it in to 5cable to power each magnet's driver
Yes.
How do I ground the arduino and the supply?
Connect them up with wire. That is the ground pin on the arduino and the -ve pin on your power supply.
Hi,
I'm back with some question's.
first of all, I was wondering. If my magnets poles are reversed my power is also reversed. This is done by my h-bridge. Does this or should this give problems for the supply?
I'm speaking 10 magnets switching currents at different moments. Or does the h-bridge take care of this.
Next question.
I'm connecting the wires to easier connectors. I see in the atx 20 pin diagram that there are +12v and -12v, what's the difference?
Which one is the -ve? the 5vsb?
Does this or should this give problems for the supply?
No. it is simply not an issue.
that there are +12v and -12v, what's the difference?
One is positive with respect to ground and the other is negative with respect to ground. It is called a split supply and gives a total of 24V between the +12v and -12v.
Which one is the -ve? the 5vsb?
I have no idea what that diagram refers to. And I am not sure what your question is here.
beyondal:
Which one is the -ve? the 5vsb?
5Vsb is the standby power that remains on even when the other supplies are shut down. It's there to keep power on to some peripherals like 'boot on LAN', even when the computer is off.
The negative of all the positive supplies is GND. The positive of all the negative supplies is also GND.
All the GNDs are connected together. This is known as a common ground system.
Hi !
I have the ATX wired to everything, except for my Arduino. I was wondering which pins I use to connect the ATX 5v to the arduino to keep everything operated stand-alone without the usb cable.
Thanks!
This is what I did, but afraid to power it because I may fry it ... 
A diagram would be easier to see.
Are you feeding 5V into the power jack? You should not do that, if you want to use 5V then it must be connected to the 5V pin.
Ow, I thought that I'll bypass the reverse diode that way and could fry the arduino?
So the safest thing would be giving 5v+ of the atx to the 5v on the arduino.
Do I give the H-bridge the 5v it needs from the Vin then?
Sorry for having no diagram!
If you have no diagram how can you wire it up?
Don't say it is in your head because that is just silly, you are not that good for that and neither am I.
You can only use Vin to power the H-bridge if it connected to the voltage needed by it.
You only need the reverse protection diode if you wire it up wrong and yes if you wire up a direct connection wrong you can fry your Arduino.
You'll might cry from this poor build schematic but this worked for the 2 magnet system I made ^^
What's you're suggestion on doing this.
What sort of H-bridge are these ( chip number please ).
I think it is a mistake connecting the Vcc2 of the H-bridge to the Vin of the Arduino, I think this should be connected to the 5V supply. But without the chip number I can't be sure.
What are the J numbers and where do they go?
VCC2 Is connected to the power supply => fault in the diagram!
So I power all the chips with the 5v of the power supply to the Vcc1's.
J numbers are the logic control and are connected to the arduino
VCC2 Is connected to the power supply => fault in the diagram!
So I power all the chips with the 5v of the power supply to the Vcc1's.
Vcc2 is the power you are using to drive the load of the chip. Vcc1 is the logic supply and should be connected to 5V. Have you read the data sheet of this chip?
So please correct you diagram and post it again. In electronics diagrams are THE form of communication.
It needs to show the connections to the H-bridge chip and the Arduino and the connections between the H-bridge chip and your magnets. Also the power supplies, you started talking about a 12V supply and now you say it is all 5V, what is it?
Have you measured what current your electro magnets take? Do you know if the power supply and the H-bridge chip will cope?
