Professional analytical classification and performance characteristics of temperature measurement and control instrument Shanghai dragon instrument electric appliance co. , LTD

Temperature measurement and control instrument can be divided into three categories: from the working principle of the pointer, digital and intelligent. Pointer instrument is given priority to with traditional moving-coil instrument, features simple structure, low price, which makes it still adopted in the industry, but its measurement precision is low, usually a grade 1 ~ 2. Level 5, reading error; No analog output, so more and more replaced by digital instrument. Digital instrument, such as is now a large number of the use of digital display table, etc. , and its measurement accuracy than the moving coil have substantial progress, ordinary is 0. 5%. The precise figures direct-viewing, without human error. Most of its control mode for two, three, there is a small amount of copy PID consecutive nursing methods. With the single chip micro disposer in instrument, the instrument appearance, structure, performance, such as the great change, it completed the mold to the function of the instrument can't imagine. This kind of intelligent digital instrument not only has the detection, conversion, and regulate function, also increased the process sequence control, fault self-diagnosis, data communications, telemetry remote control function, such as to suit with the computer connected to the request. And introduced in the previous section temperature transmitter range, select the instrument range, also should according to the practical application, upper and lower some leeway to make in the local conditions, measurement data is not beyond the range. But don't choose too large range, in order to avoid can reduce the measurement accuracy and resolution. When choosing instrument accuracy, should be thinking about what to with the variety of temperature measuring element. If mo resistance with high precision, instrument fine degrees can appropriate some taller, such as 0. 2% ~ 0. 5%. If with industrial thermocouple, the instrument accuracy is 0. 5% can. Instrument conditions should have strong adaptation ability to the environment. Ordinary, the instrument should be able to in - 10 ℃ to 50 ℃, relative humidity is less than 85% RH, the power to shake + ( 10 ~ 15) The % under the condition of normal work, and should have stronger resistance to common mode, series mode interference ability.