19 technical terms for sensor technical parameters (III)
(14) Input impedance: The input resistance of the sensor is greater than the output resistance due to the elastic compensation coefficient of the input end of the sensor and the sensitivity coefficient adjustment resistor, but it can be changed by the parallel resistance method. The input impedance of each sensor is required to be the same, if it matches the sensor of other manufacturers. The input impedance should be consistent with it, otherwise the man-hour will be increased when debugging the four-corner error, because the input impedance of the sensor is a load to the regulated power supply. Only the same load, the same regulated power supply will provide the same power supply voltage.
(15) Ultimate load (or ultimate overload): The maximum axial load that the sensor can withstand without losing its ability to work. This means that when the work exceeds this value, the sensor will be damaged.
(16) Creep and creep recovery: It is required to test the creep error of the sensor from two aspects: one is creep: the rated load is added without impact in 5-10 seconds, 5~10 seconds after loading. Read the number and then record the output value at a certain time interval within 30 minutes. The sensor creep (CP) is calculated as follows: CP = θ2 - θ3 / θn × 100%. The second is creep recovery: remove the rated load as soon as possible (in 5 to 10 seconds), immediately read the reading within 5 to 10 seconds after unloading, and then record the output value at a certain time interval within 30 minutes. The creep recovery (CR) of the sensor is calculated as follows: CR = θ5 - θ6 / θn × 100%.
(17) Sealing protection class IP67: The effect of immersion in water, the performance of immersed in water at the specified pressure and time is not affected. The glue-protected sensor can reach IP67. In addition to oil and water resistance, it can also prevent general corrosive gases and corrosive media.
(18) Temperature influence of output sensitivity coefficient (commonly known as coefficient temperature drift): This parameter characterizes the stability of the output sensitivity of this sensor when the ambient temperature changes. Generally, the drift generated in the range of 10 ° C is a unit of measurement.
(19) Cable length: It is related to the layout of the site. You must see the regular cable length of the company's products before ordering. In addition, pay attention to whether the environment is corrosive, whether there is an impact, whether it is high temperature or low temperature.
