Hi!
I'm trying to build a "simple" CNC machine but ran into some complications...
To start here is a list of my parts:
3x - 17HS19-2004S1
3x - TB6600
1x - Arduino Uno
Now the problem is that I have to make my power supply from scratch which normally isn't a problem but in this case my understanding of stepper motors is not at all big enough.
So here is my question, my steppers are rated for 2amp/phase and I'm using 3 of them. Should I build my power supply with the following specs? -> 12V 6A or should it be something else?
PS: keeping the cost as low as possible
You do not have to run the motors at max current. Set the current limit to the minimum that give reliable service with no missing steps. The motors and drivers will run cooler and last longer.
Take Chinese specifications with a grain (bushel) of salt. I would go for double.
When designing the PSU for stepper motors ( that are driven by a current driver like the TB6600 ), the power the coils need is important. The coils have a rated current of 2A and a resistance of 1.4 Ohm. That means 5.6 watts per coil. 3 motors -> 6 coils = 33.6 watt. Of course the efficency of the TB6600 is o´not 100%, so you need a safety margin. I think a 50 watt PSU should be sufficent - especially because you usually don't need to set the coil current to the max as @groundFungus already stated. To get maximum torque at high speeds, the voltage should be as high as possible ( within the limits of the driver of course )
If its as u say really tough for a 17yo to build I might talk it over with my teacher and maybe make a simple PSU for idk cooling fans, a light, ... and buy a switching PSU for 30euro's
And I suspect that nether you or your teacher has any idea about the regulations involved with laying out a PCB that has mains power directly connected on to it.
If you have to ask that then you do not have enough skill and knowledge to do this safely. This is a highly specialised area that many professional electronics engineers wouldn't know how to do.
It is possible that you could kill yourself trying to do this without proper test equipment or skills.
Y idk, I would probably assume worst case 12V 6A, and go 25% above that, might be a slight overkill, but better then a burnout, but with Chinese bought, double rating, I had manny LED drivers burn out in couple of months, and they were always rated higher then my load...
To make a switching psu, you might need arduino just to control the psu XD
A power supply for any motor, stepper or others, does NOT need to be regulated nor highly filtered. So you will need an appropriate transformer, a bridge rectifier and a filter capacitor. I don't see a problem if you can obtain the parts.
A power supply for the rest of the project is a different problem.