In the wide range of PLC's, what are the most echonomical, applicables and singles trade marks for application in control of HVAC system.
Thanks in advance.
The one that comes with good local support from an organization that has a reputation for stability and longevity. Anything else is just a collection of cheap parts that will eventaully fail. The key is being able to do something about it quickly and efficiently when it happens.
Nobody has yet made a PLC or ay other non-military control system that will never fail (and I shudder to think about military ones that probably will too).
"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more."
Nikola Tesla
I've installed recently a cooling compressor and Plc used was an Siemens S7-300. Next month were gonna install a bigger one and again were gooing to use a Siemens PLC but this time a S7-400H.
Other PLC's used or Johnson Control, Steffa, Honeywell, DDC eso.