Brief introduction of Eltra linear displacement sensor

Eltra linear displacement sensor, which is commonly known as "electronic ruler", is a special linear potentiometer. What is special: It mainly requires high precision, high repeatability, long life, and high reliability. This is not what ordinary potentiometers can do. Arrived. When no voltage is applied, the output of the linear displacement sensor is resistance. In general use, the standard voltage of 10Vdc is applied to it, and the output voltage is 0～10Vdc; or the voltage of 24Vdc is applied to it, and the output is 0～10Vdc voltage value; or apply 24Vdc voltage to it, and output 4～20mA current value through voltage/current module.

　　 Eltra linear displacement sensor use points:

　　 1. The supply voltage should be stable

　　Industrial power supply requires a stability of ±0.1%. For example, the reference voltage is 10V, and a fluctuation of ±0.01V is allowed, otherwise, it will cause the displayed trap to fluctuate. If the displayed fluctuation range at this time does not exceed the fluctuation range of the fluctuation voltage, the displacement sensor electronic ruler is normal.

　　 2. Prevent electrostatic interference

　　 Electrostatic interference and FM interference can easily make the digital display of the electronic ruler jump. Separate the strong current line of the equipment from the signal line of the electronic ruler in a wire duct. The electronic ruler should use a compulsory grounding support, and the electronic ruler housing (the resistance between the end cover screw and the support can be measured, should be less than 1Ω resistance) is well grounded, the signal line should be shielded, and one end of the electrical box should be shielded The wire is grounded. In the case of electrostatic interference, the voltage measurement of the general multimeter is very normal, but it shows the digital beating; the phenomenon is the same when the high frequency device is interfered. To verify whether it is electrostatic interference, use a power cord to short-circuit the cover screw of the electronic ruler with a certain point of metal on the machine. As long as a short-circuit, the electrostatic interference will be eliminated immediately. However, it is difficult to eliminate high-frequency interference by the above-mentioned methods, and high-frequency interference occurs frequently in robots and inverters, which can be verified by stopping the robot or the inverter power saver.

　　3. Can not connect the wrong three lines

　　 "1" and "3" lines are power lines, and "2" is output lines. Except for power lines ("1" and "3" lines) can be exchanged, "2" lines can only be output lines. Once the above wires are connected wrongly, there will be large linear errors, very difficult to control, poor control accuracy, and easy to display bounce.

　　 4. The power capacity should be sufficient

　　 If the power supply capacity is too small, the following situations are likely to occur: the mold clamping movement will cause the display of the glue injection ruler to jump, or the melt movement will cause the display of the mold clamping electronic ruler to fluctuate. Especially when the solenoid valve drive power supply is combined with the electronic ruler power supply, the above situation is likely to occur. In severe cases, the voltage fluctuation can be measured with the voltage file of a multimeter. If the problem cannot be solved even if the electrostatic interference and high-frequency interference are eliminated and the neutrality is not good, it can also be suspected that the power of the power supply is too low.

　　 5. Installation is better for neutral

　　The angle tolerance is ±12°, and the parallelism tolerance is ±0.5mm. If the angle error and parallelism error are both too large, it will cause the display number to jump. In this case, the angle and parallelism must be adjusted.

　　 6. Prevent short circuit

　　During the working process of the displacement sensor electronic ruler, the displayed data is regularly bounced or not displayed at a certain point. In this case, it is necessary to check whether the connection line insulation is damaged and the ground short circuit caused by regular contact with the machine's metal casing.

　　7. Avoid aging

　　 For the electronic ruler that has been used for a long time, the seal is aging, there may be a lot of impurities, and the mixture of oil and water, which affects the contact resistance of the brush, causing the display number to jump, which can be considered as the early damage of the displacement sensor electronic ruler itself.

　　 Yiertron linear displacement sensors are mainly used in industrial applications. In use, according to different standards, the wiring methods of linear displacement sensors are different.

　　Notes on wiring of linear displacement sensor:

　　 1. Linear displacement sensor (commonly known as electronic ruler), the power supply voltage is generally 5v-36v, not more than 36v, otherwise it is easy to burn the circuit.

　　2. The power supply voltage must be stable. The industrial power supply requires a stability of ±0.1%. For example, the reference voltage is 10v, and the fluctuation of ±0.01v is allowed. Otherwise, it will cause larger fluctuations in the display. If the displayed fluctuation range at this time does not exceed the fluctuation range of the fluctuation voltage, the linear displacement sensor (electronic ruler) is normal.

　　3. The power supply must have sufficient capacity. If the power supply capacity is too small, the following situations are prone to occur: the mold clamping movement will cause the injection linear displacement sensor (electronic ruler) to display bounce, or the melt movement will cause the mold clamping electronic ruler to display fluctuations. Especially when the solenoid valve drive power supply is combined with the electronic ruler power supply, the above situation is likely to occur. In severe cases, the voltage fluctuation can be measured with the voltage file of a multimeter. If the problem cannot be solved even after eliminating the electrostatic interference, high frequency interference, and poor neutrality, you can also suspect that the power of the power supply is too low.

4. The three wires of the linear displacement sensor (electronic ruler) cannot be connected wrongly. Line 1# and 3# are power lines, and line 2# is the output line. Except for the power lines of line 1# and 3#, which can be exchanged, line 2# can only be Output line. Once the above line is connected wrongly, there will be large linear errors, poor control accuracy, and easy display bounce. If it is very difficult to control, it should be suspected to be the wrong line.