[PIC] Microcontroller industrial control

[leorickings]

Hi, I'm working on a project to control valves, one at 240Vac and another at 24Vdc. The system is controlled with a PIC microcontroller. I have been searching for info on interfacing microcontrollers to the industry world, but found literally nothing. Why isn't there anything about this? How do the industry achieve high power control with logic level controllers?

I have been trying the simplest solution - relays. Out of so many products, I found a relay with 5Vdc coil, which I can drive with a transistor from the microcontroller, with 230Vac / 24Vdc contact. But this component is so rare that none of the suppliers are willing to supply unless in a massive quantity.

Optocouplers and TRIACS are super rare too, especially the ones matching my requirements....

Please help, I believe there is not only me facing this problem

 

[cameo_2007]

But this component is so rare that none of the suppliers are willing to supply unless in a massive quantity.



Please help, I believe there is not only me facing this problem

I do not believe this. Where are you located? This is the right solution for you and you should not find a problem in sourcing the relay in lesser quantities.
Any electronics component shop will have this.

 

[richardlaishram]

So you are going to control Solenoid valves using Microcontrollers? For switching DC, MOSFET can be used as a switch and a transistor to drive it from a Microcontroller. For AC switching I can think of Relays only.

 

[ftsolutions]

Yes, it should be quite easy to get relays of the appropriate type. How many amperes do you intend to switch? Depending on your application, you may want to use a MOSFET based switch, or a solidstate relay that will switch at zero crossover of the AC power, but I don't have enough info from your post to tell if it is necessary. You may need to drive the relay with a transistor circuit to handle the voltage/current requirements of the relay (coil or solid state) for proper switching. Ixys (Clare) make some nice solidstate relays if you need to be switching significant power - they offer bidirectional solidstate relays/switches for handling AC as well.