can someone tell me some advantages of pneumatic controllers versus electrical controllers? i can't seem to find any answer on the web it only shows up all this complicated stuff. i'm not that good at process tech yet...
The only advantages I see is, it being a pneumatic controller, it is safe to put it in hazardous area, close to your process, so in situ tuning of process parameters can be done.
Disadvantages could be many many, a few are:
1. Moving parts - more maintenance
2. Pneumatic signal travels slow
3. No autotuning or any complex control
4. Manual adjustment is required
5. May drift after continuous operation
6. More costly to operate - compressed air is energy, more maitenance
Sometimes you see pneumatic controllers running on other than air, I have seen them on natural gas. Pneumatics is also good for local control in wet areas e.g. flotation level control in mining. Even so I have not purchased one in over 20 years. Most electronic controller output signals still convert back to pneumatics at the control valve.
Following points are the advantages of pneumatic over electrical drives
1. Safe to use
2. Only Semi-skilled manpower required for operation and maintenance
3. Best for use in inflammable area.
4. No mechanical overload/thermal overload dysfunction.
5.Far more cost-effective as compared to electrical actuators.
6. Far less moving parts inside, hence lower maintenance requirement.
7. Light in weight, yet sturdy in design.
8. By design Ingress protected.
9. Cheaper & lower technology options for control of speed.
10. Even considering investments on compressor, the pneumatic actuators are far more cost effective in terms of cost of ownership and return on investment.
Trust the above will help you choose the actuators. Please do revert in case of any further information/clarification/deviation in opinion.
Facebook
Google
GitHub
Linkedin
