Views: 46 Author: Site Editor Publish Time: 2024-12-30 Origin: Site
◆ VPC Official Spanish Language Website
The main function of the auto reed switch is to check the operation of the cylinder piston so that the piston rod can be fixed and stopped at a certain position. It is usually used in conjunction with a solenoid valve to detect the position of the cylinder and complete the movement of the cylinder. It has the following characteristics:
1. Strong versatility, suitable for a variety of pneumatic cylinder types.
2. High sensitivity, small size, fast response, long life.
3. Easy to install, no noise, and equipped with LED indicator.
1. Working Principle
When the cylinder's magnetic ring moves close to the reed switch, the magnetic reed of the magnetic switch will be sensed, causing the electric shock to close and generating an electrical signal.
When the magnetic ring leaves the induction switch area, the magnetic reed loses its induced magnetism, causing the electric shock to disconnect and the electrical signal to disappear.
In this way, the position movement of the cylinder piston can be checked, thereby controlling the corresponding solenoid valve action.
2. Types of magnetic switches
Type | Contact type magnetic reed switch | Contactless electronic switch |
Working Principle | The metal reeds are magnetized and attracted to each other under the action of the magnetic field, thus conducting the circuit and sending out a signal. Such as a reed switch or a magnetic reed switch. | Based on electronic components to sense magnetic field and output signals. There is no mechanical contact, and the switching action is achieved through electrical signals. Such as Hall sensor or magnetoresistive sensor. |
Voltage range | 5V-240V DC/AC | 5V-30V DC |
Output signal | The output is a simple on/off signal, suitable for simple circuit control. | The output signal is available in various forms (such as PNP/NPN, analog signals, etc.), which is compatible with modern automation systems. |
Application | Suitable for low-frequency, non-critical control occasions, such as simple position detection. | It is suitable for occasions with high frequency, high precision and high anti-interference requirements, such as industrial automation and high-speed cylinder control. |
Contact type magnetic reed switch
Contactless electronic switch
3. Factors to consider when selecting a reed switch
① Type of pneumatic cylinder | Different types of cylinders have different installation methods and corresponding magnetic switch models. The stroke of the cylinder and the use environment should also be considered. |
② Load voltage | - Contact-type reed sensor are suitable for a wide range of voltages, including AC and DC. - Non-contact types are usually suitable for voltages below 30V. |
③ Use wire system | - Most magnetic switches with contacts are 2-wire type. The core reed tube has no polarity, but since magnetic switches generally have indicator lights, if they are connected in reverse, the switch will work but the indicator light will not light up, or the indicator light will be damaged and the switch will not work. - The contactless type uses semiconductor components, which are generally 3-wire, divided into NPN type and PNP type (mostly NPN is used in Asia Pacific and Japan, and PNP is commonly used in Europe). Whether the contactless type is 3-wire or 2-wire, it cannot be reversed because the components it uses have polarity. |
④ Suitable load | Such as relays, program controllers, IC circuits, solenoid valves, etc. |
⑤ Mounting method | There are four mounting methods: direct, bracket, band, and tie-rod mounting, etc. |
*The premise of using a magnetic switch is that it must be used with a magnetic cylinder, that is, the piston has a magnetic ring.
Rail mounting
Band mounting
Direct mounting
Bracket mounting
Tie-rod mounting
4. Safety inspection
① Since the magnetic switch is often in working condition, regular maintenance and inspection are required to prevent the switch from malfunctioning.
② Check the working environment of the magnetic switch and keep the environment dry and at normal temperature.
③ Check whether the wire is damaged. Damage to the wire will cause poor insulation or wire breakage. If the wire is found to be damaged, the switch should be replaced or the wire should be repaired.
④ Tighten the small screws of the induction switch to prevent the induction switch from loosening or shifting; if it has shifted, it should be readjusted to the correct position and then tightened.
Of course, in addition to being used with magnetic switches, the air cylinder can also be connected with a variety of other accessories to achieve different functions and enhance performance, such as pneumatic cylinder accessories, solenoid valves, speed control valves, connectors, etc.
Supplementary content
Magnetic Switch VS Proximity Switch
Aspect | Magnetic Switch | Proximity Switch |
Working principle | Detection is done by sensing changes in a magnetic field. (such as a magnet or a magnetic ring inside a cylinder piston) | Detection through the electromagnetic field of the sensing object, metal object or medium change. |
Detection object | - Magnetic objects or magnetic components (such as cylinder pistons) | - Metal (inductive) - Metal and non-metal (capacitive) |
Installation | Usually installed near the cylinder or other magnetic components. | For stand-alone installation or testing of non-magnetic equipment. |
Usage Environment | Small, narrow, compact installation environment. | Strong magnetic field or magnetic interference environment. |
Application | - Cylinder piston position detection - Signal feedback of pneumatic system - Multi-point position detection - Application in dusty, vibrating or harsh environment | - Metallic or non-metallic object detection - Automated equipment detection (such as limit control, counting or flow monitoring) - High-speed object detection - Non-magnetic environment application |
The above is about how to choose a reed sensor and the difference between a magnetic sensor and a proximity sensor. If you have any other questions, please contact VPC. We will be happy to provide you with more professional help in pneumatics.