The rotary switch is a common circuit control component that realizes multi-gear switching or continuous adjustment through rotation operation.
This article will introduce the definition, working principle, application occasions, main types of rotary switches in detail, as well as how to choose a suitable rotary switch according to actual needs, to help readers fully understand this commonly used electronic component.
What is Rotary Switch？
A rotary switch is a switch that controls the on and off of a circuit by rotating. It usually consists of a rotating shaft and multiple contact terminals. There is a contact arm on the rotating shaft, which can be rotated to make the contact arm contact different terminals, thereby switching different circuits.
Working principle of rotary switch
The working principle of rotary switch is to use the contact arm on the rotating shaft to rotate within a certain range and contact with the fixed contact terminal, thereby changing the connection state of the circuit.
When rotated to a specific position, the contact arm will contact the corresponding terminal to make the circuit conductive; when rotated to other positions, the contact arm will be separated from the terminal and the circuit will be disconnected.
Uses of rotary switches
Rotary switches are often used in electrical appliances and equipment that require multi-position switching, such as:
- Channel and volume adjustment of old-fashioned TVs and radios
- Multi-position speed regulation of electric fans
- Range selection of instruments and meters
- Function switching of audio equipment
Types of Rotary Switches
Depending on the structural form and purpose, rotary switches can be divided into several types:
- Single-pole rotary switch: only one set of contacts, used for on-off control of a single circuit.
- Multi-pole rotary switch: has multiple sets of contacts, which can control multiple independent circuits at the same time.
- Multi-gear rotary switch: realizes the switching of multiple gears in one switch, such as 3 gears, 4 gears, etc.
- Encoder rotary switch: outputs a digital encoding signal corresponding to the rotation position.
- Momentary rotary switch: It will automatically rebound when rotated to certain positions, and is used for instantaneous control.
- Waterproof and dustproof rotary switch: It has a sealed structure and is suitable for harsh environments.
How to choose the right Rotary Switch?
Choice of the number and type of contacts
Choose a rotary switch with different numbers of contacts such as single pole, double pole, three pole or four pole according to the requirements of the circuit design. The contact material can be selected from silver alloy, copper silver plating, gold plating, etc. to meet different use environments and life requirements.
Evaluation of load capacity and electrical characteristics
It is necessary to evaluate the current, voltage, power and other parameters that the rotary switch needs to switch in actual applications, and select a model that meets the load requirements. At the same time, electrical performance indicators such as contact resistance, insulation resistance, and withstand voltage should be considered.
Consideration of installation method and overall size
According to the structural layout of the equipment, choose a suitable installation method, such as panel installation, PCB board installation, etc. At the same time, it is necessary to consider whether the overall size of the rotary switch matches, and whether the size and style of the operating knob meet the usage requirements.
FAQs
Q1:What should I do if the rotary switch fails?
A1:Common causes of failure include damaged connecting cables and worn switch components. You can check whether the cable connection is good and repair or replace it if necessary. It is also important to clean and maintain the switch regularly. If the switch circuit is damaged, professional repair is required.
Q2:What is the internal structure of a rotary switch?
A2:A rotary switch is essentially a knife switch that connects or disconnects the circuit by rotating the handle left and right. It consists of multiple contacts, which can be divided into multiple gears according to the number of contacts. Common rotary switches include the HZ10 series.
Q3: How to prevent rotary switch failure?
A3: Regularly clean and maintain the equipment, and lubricate key components. Check whether the power supply and wiring of the equipment are normal. If the switch parts are found to be worn, they should be replaced in time. These will help reduce the occurrence of failures.
Q4:What is the difference between rotary and selector switch?
A4:A rotary switch is a switch in which contacts and connections alternate when the spindle is rotated clockwise or counterclockwise. The selector switch turns rotates the handle to turn the circuit on or off at different currents. Controls different circuits with a single switch.
Conclusion
Rotary switches are widely used in various electronic devices due to their advantages such as multi-gear switching and convenient adjustment.
When choosing a rotary switch, you need to consider factors such as the number of contacts, load capacity, electrical performance, and installation method to meet specific usage requirements.
