Pressure not only needs to be measured, but your system needs to make changes based on pressure readings as well. The system controller(s) can adjust the system based on the input it receives from various measuring devices. Controllers are necessary for ensuring the safety of the system. They also will help contribute to the long-term efficiency, reliability, and data-mining of the system.
Pressure transducers produce electrical signals that feed into a controller. The controller then reads the input signal and can adjust the system pressure in according to keep the system variable within a certain range. That variable could be anything from the number of chocolates dipped per minute to a certain temperature. Simply put: choosing the right controller for your system is a key decision that many engineers do not put enough time into.
In regards to pressure reading, a controller can release and close valves -- among other things -- to keep pressure in the system within a certain range. Choosing the right pressure transducer controller is imperative for your system’s long-term success. There are two options that engineers can use to incorporate pressure monitoring and controls into their system.
Pressure transducers use a variety of measuring techniques to take a pressure reading and turn it into an electrical signal. The electrical signal will normally be fed from the transducer and into the controller. The controller, in this case, is a separate unit from the pressure transducer in the system. Most industrial and complex systems will require the controller to be separate from the pressure transducer in order to achieve the proper accuracy.
For systems where there are multiple pressure transducers, having the controller distinctly separate will allow for a more reliable system. With multiple pressure readings coming from multiple pressure transducers, having a central controller can be beneficial for a number of reasons. If your system is robust enough, having multiple pressure transducers and controllers is unavoidable. The controller can manage separate parts of the system and keep the system’s pressure in check.
A pressure controller is more or less a pressure transducer and controller all packed into one device. That may sound appealing to nearly everyone, but caution should be taken when incorporating a pressure controller into any system. With every component built into one device, there is greater risk for the system if the pressure controller drastically fails. Pressure controllers generally have a limited number of inputs and outputs. In large systems, pressure controllers simply will not work.
For low-level applications this may be the best choice for your systems, as this device will be more cost-effective. The device will measure the pressure and control aspects of the system.
At the end of the day, it all depends on your system’s application and unique needs. Here are a few characteristics to keep in consideration when evaluating your system design. These will help get your head in the right space to think about the pressure transducer controller requirements.
Most controllers can be programmed to meet a system’s specific needs. There are controllers that allow engineers to create highly customized programs that can accurately control the system’s various pressures. Some applications need very little programming as they are simply not that complex.
Number of Inputs and Outputs
The smaller the system is, the easier it is to find a controller that will suit your needs. Smaller systems, which are considered less than 300 inputs and outputs, do not need a complex controller to successfully operate. If your system has more than 300 inputs and outputs, you will be faced with a more sophisticated (and expensive!) controller.
The pressure transducer controller still has to function in the system’s environment. In many industrial applications the environment can be extremely harsh. Dust, high or low temperatures, high pressure, and many other factors can completely render a functional controller inoperable.
There are many other factors that need to be considered, but these will give your team a starting point. Carefully develop the system requirements and they will show you exactly what controller you need for your system.
- What is a pressure transducer?
- How do pressure transducers work?
- Pressure sensor vs transducer
- Custom pressure transducers
- Pressure transducers FAQ
- Selecting a pressure sensor
- How to specify
- Installing a pressure transducer
- Selecing an amplifier
- Selecing a controller
- Selecing a data logger