Compact controller
Compact controllers are independent control systems that can control one or more control loops . The controllers can be parameterized and so on any type of controlled system to be adjusted. Simple versions have a numerical display of the process values. Compact controllers with sophisticated equipment are available with a touchscreen and graphic display of the controlled system or the system.
In addition to the actual control task, compact controllers can also take on control tasks and thus independently control the course of the process or parts of it.
Compact controllers can be found in almost all branches and branches of industry, for example the program controller function is often used in the food industry or in hardening shops to specify certain temperature profiles. Compact controllers are also used, for example, in house connection stations to regulate heating and hot water preparation or for simple ventilation systems.
construction
Compact controllers are either fixed or modular and therefore expandable. The analog inputs for the actual value can often be used universally and can be configured for different types of sensors and signals. Digital inputs are also available for recording switching processes. Various binary switching elements are available as outputs such as relay, semiconductor relay, logic and MosFET outputs and are used either to control binary actuators or for control signals. The analog outputs can be configured as voltage or current outputs e.g. B. 4… 20 mA / 0… 10 V and are used for continuous control of analog actuators such as B. proportional valves , thyristor power controllers or frequency converters are used.
Operation, parameterization and configuration can be carried out via the front of the device; configuration programs are also supplied in which the settings can be easily accessed by the user. The connection between PC and controller can be established via USB, TCP / IP or serial interfaces.
Controller types
Depending on the equipment of the outputs, the following controller types can be configured:
- Continuous controllers for analog actuators
- Two-point controller for binary actuators
- Three-point controller for binary and / or analog actuators to control in both directions
- Three-point step controller for motor actuators
- Positioner for motor actuators with position feedback
Special functions
The program controller function provides the controller with a user-defined setpoint profile, which is divided into several sections. The controller then no longer works with a fixed setpoint, but is given this by the program. The system can thus approach certain setpoints at defined times. In addition, the individual sections can be assigned control contacts in order to control additional actuators .
In the case of compact controllers with a color display, a registration function is often available, in which important process data are recorded and archived, as with the paperless recorder.
Individual evidence
- ↑ a b c d Manfred Schleicher: Control engineering - Basics and tips for the practitioner . Jumo, Fulda 2014, ISBN 978-3-935742-00-9 ( free full text [PDF; 3.2 MB ]).