There is nothing really magic about PLCs. You could well make a PLC with an Arduino if you wanted to. But as many have said, is it worth it?
I design and make industrial control equipment and they are not PLCs but dedicated devices. One thing to make sure in your design is to do your best to have bullet proof power supply and I/O interfaces.
If you go the way of Arduino, make sure you document it well as to allow someone else to take over if needed.
Do you want the device to run PLC ladder logic or just have a custom controller to do a job? Custom is ok. None of the devices I've been involved in has come anywhere near ladder logic. And there are vary many different installations running, from controlling a portable sawmill, wrapping candy bars, running irrigation systems, motor control....
One of my irrigation monitors is an Arduino Mini Pro as the complete little board is cheaper to buy than the parts to make it.
In fact as I type this, I just got a text from one of them to tell me it is still running
So after that long waffle, an Arduino can quite well work for you, but the down side will be it is custom so maintaining it in the future could be a problem. And you will have to design the electronic interface and power supply as well as the programming. There could be legal problems with certifications in some places if that is needed. But if it is for your own use, have a go.
I design and make industrial control equipment and they are not PLCs but dedicated devices. One thing to make sure in your design is to do your best to have bullet proof power supply and I/O interfaces.
The Arduino does not have this but that is not a problem as such. The PLC brain at CPU level does not either. The interface to the real world is a design feature. Most of my boards run on 24V as that is one of the main standards of industrial control equipment. It does not matter what controller you use, just build accordingly, like opto isolate as you can and put lots of bypassing and transient protection in. For industrial control, overkill is good. the environment can he pretty harsh. Use high temperature components. That is one thing an off the shelf Arduino will lack.Hello,
Many PLC's use signal levels of 24 Volts.
The arduino or other microcontrollers will not accept those levels.
You will need to convert the levels to the ones accepted by the arduino or other microcontroller.
Bertus
If you go the way of Arduino, make sure you document it well as to allow someone else to take over if needed.
Do you want the device to run PLC ladder logic or just have a custom controller to do a job? Custom is ok. None of the devices I've been involved in has come anywhere near ladder logic. And there are vary many different installations running, from controlling a portable sawmill, wrapping candy bars, running irrigation systems, motor control....
One of my irrigation monitors is an Arduino Mini Pro as the complete little board is cheaper to buy than the parts to make it.
In fact as I type this, I just got a text from one of them to tell me it is still running
So after that long waffle, an Arduino can quite well work for you, but the down side will be it is custom so maintaining it in the future could be a problem. And you will have to design the electronic interface and power supply as well as the programming. There could be legal problems with certifications in some places if that is needed. But if it is for your own use, have a go.