What are control units?
Pushbuttons, key switches, selector switches, emergency-stops, pilot lights, knobs for potentiometers, enabling switches, RFID, capacitive pushbuttons
Control units are essential components in the industrial automation and control technology. They are used to control machines and installations, start or stop processes and signal operating statuses. Control units are used in numerous application areas, from production lines to switching stations to safety-critical applications.
Overwiev control unitsTypes of control units
There are various types of control units which are selected depending on their function and field of application. The most important ones are:
Pushbuttons are mechanical components that open or close an electrical contact when a button is being pushed. They are often used to control machines and processes and are available in various colours and designs.
pushbutons
A key switch can only be operated with the suitable key, meaning it offers additional protection against unauthorised access. These switches are often used in safety-related applications or for authorisation of certain users.
key switches
Selector switches enable to change between various switching positions. They are for example used to select an operating mode or different machine functions.
selector switches
An emergency-stop is a safety-critical component that is activated in case of emergency to immediately stop machines and thus prevent accidents. In general, they have a red colour with yellow background and a latching mechanics which precnets an unintentional reset.
emergency-stops
Pilot lights fulfill the fuction of optically signaling the status of machines and plants. They can be illuminated in various colours to indicate different statuses like readiness for operation, errors or alerst.
pilot lights
A knob for potentiometers is a rotary knob for a stepless setting of voltages or resistances. It is used for the control of motors, lighting systems or electronic control circuits.
knobs for potentiometers
RFID control units enable a contactless identification and control of machines and plants. They are often used in safety-critical areas to permit access to certain functions for authorised personnel only.
RFID
Enabling switches are safety-relevant control units that are often used in robotics and automation. They have to be actively pushed to activate a machine and act as an additional safety measure against unintended switching on.
enabling switches
Capacitive pushbuttons react to touch or mechanical operation. They are specially wear-free and are often used in hygienic areas or demanding ambient conditions.
Conclusion
FAQs
What are control units used for?
Control units are used for the control and monitoring of machines and plants by activating commands or indicate operating statuses.
What is the difference between a pushbutton and a selector switch?
A pushbutton activates a switching circuit by pushing, whereas a selector switch can enable various switching states that are selected by twisting it.
Why are emergency-stops so important?
Emergency-stops are essential for safety as they switch off machines and plants in a case of emergency immediately to prevent accidents.
What colours do pilot lights have and what do they mean?
Where are key switches used?
Key switches are used where unauthorised access has to be prevented, e.g. for safety-critical controls or the enabling of a machine.
What is the benefit of a potentiometer knob?
Knobs for potentiometers enable stepless regulation of electrical values like voltage or resistance and thus can be used flexibly.
Are there industry standards for control units?
Yes, a lot of control units comply with international norms such as IEC 60947 which define requirements for safety and function.
How do I choose the appropriate control unit for my application?
The choice depends on the specific application, the required functions and the safety requiremetns. A professional consultation can help to make the best choice.
