German SICK encoder SICK model SICK price

SICK encoder is a new type of angle or displacement measurement device. Its principle involves using magnetoresistive elements to measure the angle or displacement of changing magnetic materials. Changes in the angle or displacement of the magnetic material cause changes in resistance or voltage, which are processed by a microcontroller to output pulse signals or analog signals for measurement purposes. Concentric code tracks extend from the center of the magnetic encoder disk outward to the edge, with each layer having twice as many segments as the inner layer. The first layer has only one transparent sector and one opaque sector; the second layer at the center has two transparent sectors and two opaque sectors; and the third code track has four transparent sectors and four opaque sectors. The built-in sensor head is compact, suitable for small installation spaces, and features a high protection rating design, making it suitable for harsh environments. In industrial applications, it avoids the sensitivity to pollution typical of optical encoders, increasing long-term system stability.

SICK encoder principle

Magnetic encoders use a magneto-electric design, where changes in the magnetic field of magnetic sensing devices generate or provide the position and speed of the actuator (servo motor). The physical working principle of magnetic encoders is the magnetoresistive effect. This effect arises from charge carriers inside a current-carrying conductor or semiconductor under the influence of the Lorentz force, causing the trajectory of internal charge carriers to deflect or spiral, thereby changing the potential difference within the conductor or semiconductor. This is a microscopic manifestation; macroscopically, as the external magnetic field changes, the magnetoresistance value changes accordingly. This is the magnetoresistive effect of magnetic encoders. Magnetoresistive devices in magnetic encoders include semiconductor magnetoresistive devices and ferromagnetic magnetoresistive devices. Thus, the detection probe of a magnetic encoder uses magnetoresistive devices as the magnetic head. Currently, common magnetoresistive heads for magnetic encoder probes include Giant Magnetoresistance (GMR) heads (GMR) and Anisotropic Magnetoresistance (AMR) heads (AMR). However, due to advantages such as better frequency characteristics and higher sensitivity compared to GNR heads, AMR heads are gradually becoming the mainstream application for magnetic encoder heads.

Main functions of SICK encoder

It is a rotary sensor that converts rotational displacement into a series of digital pulse signals. These pulses can be used to control angular displacement. If the encoder is combined with a rack and pinion or a lead screw, it can also measure linear displacement. After the encoder generates electrical signals, they are processed by numerical control devices CNC, programmable logic controllers PLC, control systems, etc. These sensors are mainly applied in the following areas: machine tools, material processing, motor feedback systems, and measurement and control equipment. In ELTRA encoders, the conversion of angular displacement adopts the principle of photoelectric scanning. The reading system is based on the rotation of a radial graduated disk, which consists of alternating transparent and opaque windows. The entire system uses an infrared light source for vertical illumination, projecting the image on the disk onto the surface of a receiver. The receiver is covered with a grating, called a collimator, which has windows identical to those on the disk. The receiver's function is to sense light changes produced by the disk's rotation and convert these light changes into corresponding electrical changes. Generally, a rotary encoder can also obtain a speed signal, which is fed back to the frequency converter to adjust its output data. Fault phenomenon: 1. When the rotary encoder fails (no output), the frequency converter cannot operate normally, running very slowly, and then triggers protection, displaying "PG disconnected"... Joint action is required for proper operation. To raise the electrical signal to a higher level and generate square wave pulses without interference, electronic circuits must be used for processing. Encoder pg wiring and parameters: The connection method between the vector frequency converter and the encoder pg must correspond to the encoder pg model. Generally, encoder pg models are divided into differential output, open-collector output, and push-pull output. The signal transmission method must consider the interface of the frequency converter pg card, so selecting the appropriate pg card model or setting it reasonably is essential. Encoders are generally classified as incremental or absolute. The biggest difference is: in incremental encoders, position is determined by counting pulses from a zero mark, while in absolute encoders, position is determined by reading the output code. Within one revolution, the output code reading for each position is unique; therefore, when power is disconnected, the absolute encoder does not lose track of the actual position. If power is restored, the position reading remains current and valid; unlike incremental encoders, there is no need to find the zero mark. Encoder manufacturers produce comprehensive series, usually specialized, such as elevator-specific encoders, machine tool-specific encoders, and servo motor-specific encoders. Furthermore, encoders are intelligent and have various parallel interfaces for communication with other devices. An encoder is a device that converts angular or linear displacement into electrical signals. The former is called a code disk, and the latter a code scale. According to the readout method, encoders can be divided into contact and non-contact types. Contact types use brush outputs, where a brush contacts a conductive or insulating area to indicate whether the code status is "1" or "0"; non-contact types use photosensitive or magnetic-sensitive elements as receiving sensitive components. When using photosensitive elements, transparent and opaque areas indicate whether the code status is "1" or "0". According to working principles, encoders can be divided into incremental and absolute types. Incremental encoders convert displacement into periodic electrical signals, which are then converted into counting pulses, with the number of pulses representing the magnitude of displacement. Each position of an absolute encoder corresponds to a specific digital code, so its indication depends only on the start and end positions of the measurement, not the intermediate process. Rotary incremental encoders output pulses during rotation, and their position is known through counting equipment. When the encoder is stationary or power is lost, the position is remembered by the internal memory of the counting equipment. Thus, after a power loss, the encoder must not move, and during pulse output upon power restoration, no pulses must be lost due to interference; otherwise, the zero point memorized by the counting equipment will shift, and the amount of this shift is unknown until erroneous production results appear. The solution is to add reference points; each time the encoder passes a reference point, the reference position corrects the memorized position in the counting equipment. Before the reference point, position accuracy cannot be guaranteed. Therefore, in industrial control, methods such as finding the reference point before each operation or homing at startup are used. Such encoders are determined by the mechanical position of the code disk and are unaffected by power loss or interference. Absolute encoders determine the uniqueness of each position by mechanical position, requiring no memory, no search for reference points, and no continuous counting. The position is read whenever needed. Thus,the anti-interference characteristics and data reliability of the encoder are greatly improved. Since absolute encoders are significantly superior to incremental encoders in positioning, they are increasingly used in industrial control positioning. Due to the high precision and large number of output bits of absolute encoders, if parallel output is still used, every bit of the output signal must ensure a good connection, and isolation is required for complex conditions. This results in many cable cores, causing inconvenience and reduced reliability. Therefore, for multi-bit output absolute encoders, serial or bus-type output is generally selected. For German-produced absolute encoders, the most common serial output is SSI (Synchronous Serial Interface). Multi-turn absolute encoders. Encoder manufacturers apply the principle of clock gear mechanics. When the central code disk rotates, another set of code disks (or multiple sets of gears and code disks) is driven via gear transmission. This adds turn-count encoding to single-turn encoding, expanding the measurement range of the encoder. Such absolute encoders are called multi-turn absolute encoders. They are also determined by mechanical position, with unique, non-repeating codes for each position, requiring no memory. Another advantage of multi-turn encoders is the large measurement range, often providing ample margin in actual use. Thus, during installation, there is no need to struggle to find the zero point; a middle position can serve as the starting point, greatly simplifying installation and commissioning. Multi-turn absolute encoders have obvious advantages in length positioning and are increasingly used in industrial control positioning.

SICK encoder applications

This encoder uses relative counting for position measurement. Before operation, programming stores the pulse counts corresponding to various signals, such as speed change points, leveling points, and braking stop points, into respective memory units. During elevator operation, the rotary encoder detects and software calculates the following signals in real time: elevator floor position, speed change point position, and leveling point position, thereby performing floor counting and issuing speed change and leveling signals.

Weidou Intelligent Technology professionally sells German SICK rotary encoders, SICK incremental encoders, SICK absolute encoders, SICK photoelectric encoders, SICK magneto-electric encoders, SICK shafted encoders, SICK hollow shaft encoders, SICK contact brush encoders, SICK angle encoders, SICK linear encoders, SICK digital encoders, SICK draw-wire encoders, SICK position encoders, SICK hollow bore encoders, SICK spindle encoders, SICK original German imports. Welcome customers to inquire and order.