What is the reason for the abnormal pressure signal of the central control card?
A: The pressure signal is in full scale, which is inconsistent with the actual situation. Disconnect the positive pole of the signal line behind the card, and the signal changes from full scale to about 8kg pressure signal (the range is 0-13kg). After field observation, the measuring point passes through the safety barrier. Short circuit the signal line, but the signal display is normal after the safety barrier.
Preliminary judgment is that there is a problem with the safety barrier. The reason may be that the signals of the same group and the safety barrier are grounded together. When the safety barrier fails, another Ma signal is coupled to the signal, resulting in signal interference.
How to check the inaccurate thermal resistance signal?
A: Firstly, check the configuration of thermal resistance and confirm that the thermal resistance model in the configuration is consistent with the actual model; Secondly, ensure that the upper and lower computer configurations are consistent. Then, if it is still suspected that there is a problem with temperature measurement, the resistance between on-site thermal resistance a and B can be measured as R1; The resistance between B and C is R2.
According to the temperature measurement principle of 3-wire thermal resistance, the actual resistance value of thermal resistance can be obtained as r1-2r2. Then check the table to find out the corresponding temperature. Then compare this temperature with the temperature on the monitor. If the access is large, please replace the card and try again.
The above is a detailed introduction to the DCS card of central control of Zhejiang University. I hope it will be helpful to you If you have any questions, please contact us We will provide you with professional service http://www.sdjkyqyb.com