I. Overview:

Conductive plastic displacement sensor is a non-wire wound potentiometer with a linear relationship between voltage output and shaft rotation angle or linear displacement. It is characterized by high precision, long life, high smoothness and high resolution. Can be used for position feedback, position detection, level adjustment, etc.

The sensor structure is mainly composed of resistive elements, shafts, brushes, shells, covers, etc.

There are two types of rotary sensors: single-connection and double-connection. They have the same installation form and are divided into nut fixing (such as WDD32 type) and screw fixing (such as WDD35D type). The electrical signal is generally drawn out in the form of a terminal.

The installation form of the straight-sliding sensor is generally fixed by screws, and there are three forms of electrical signal extraction: terminal type (such as: WDM14 series), socket type (such as CFY electronic ruler series) and wire type (such as CWY series).

2. Wiring method and principle:

Schematic:

The three binding posts or red, yellow, and blue lines correspond to the signs 1, 2, and 3, respectively: 1 is the input end; 2 is the output end; 3 is the grounding. (Please note: If the wrong wire is connected to the terminal 2, the sensor will be burnt out.) When the shaft rotates angularly from the 1st end to the 3rd end or the resistance changes linearly, the output from the 2nd end is high-precision according to the linear law. The value change is converted into a signal display.

Third, the use of voltage instructions:

The sensor uses DC voltage, which is added to the rated voltage of terminals 1 and 3 (two fixed terminals).

calculation method

U - rated voltage (V)

P - Rated power (W)

R - Nominal resistance (Ω)

4. Installation:

1. Position the sensor mounting boss and fasten it on the metal plate with screws, nuts or pressure plates. When installing the sensor, it is strictly forbidden to process the shaft and casing, such as turning and drilling, so as to avoid the shaft or casing from being subjected to external impact force and pressure. 300N). It is strictly forbidden to loosen the screws on the sensor and turn the position of the tightening ring.

2. When connecting the sensor shaft with other parts, it should be noted that the axis line should be kept in a straight line (including the working state). If there is a deviation in the axis line, it is recommended to use a universal joint or a The sensor output shaft is bent and deformed, which damages other devices, thus affecting the use.

3. Water droplets, steam, solvents and corrosive gases should be prevented from attacking the sensor, and metal chips or other powders should be prevented from entering the sensor.

4. The external wiring of the sensor should be welded at the waist groove of the lead-out end, and try not to be welded on the top of the lead-out end. Welding should use no more than 45W electric ferrochromium, and the welding time should be less than 5 seconds. The wire should not be pulled when it is welded or not cooled thoroughly, so as to avoid the brush wire or the entire terminal being pulled out or even falling off. When welding, try to use as little flux and welding oil as possible, and the time should be short, so as to avoid the flux vapor entering the sensor through the terminal, which will cause the vapor to be deposited on the surface of the resistance element after cooling, resulting in the deterioration of the equivalent noise resistance, or even an open circuit.

5. Notes:

1. After the sensor leaves the factory, the manufacturer is not responsible for the warranty service for products that are disassembled or modified by the user (including tearing off the trademark, processing on the shaft and housing, loosening the screw, turning the position of the fastening ring, etc.).

2. When the sensor is connected to the line, it is strictly forbidden to connect the wrong terminal, and pay special attention to the brush terminal (2#), which cannot be connected to the input voltage.

3. When the sensor is powered on, be careful not to measure the sensor voltage with the resistance gear and current gear of the multimeter.

4. The sensor should not be thrown around during the installation process, so as not to damage the terminal.

5. The sensor should be guaranteed to be within the rated power consumption range when the voltage is applied. (Note here that the rated power consumption refers to the allowable power consumption of the sensor when the ambient temperature is 70°C, and the power should be reduced when it exceeds 70°C).

6. The current through the sensor brush is recommended to be 2mA, and the maximum value should not exceed 10mA.

7. Sensor and accuracy refer to the compliance accuracy of the output characteristics, not the deviation accuracy of the total resistance value.