DCS and SIS communication issues
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Our company uses HaliTech DCS/M6 and SIS/Tricon 1131 for communication, with the SIS transmitting data to the DCS. The current issues are as follows: 1. The communication point alarms received by the DCS show either overreporting or underreporting. Check the SIS; there are no alarms at this point in the SIS. 2. All cabinet clips are in good condition. 3. There is an alarm for the communication points transmitted by the same communication card module. 4. Alarms from communication points occur at irregular intervals, with the locations of these points being random. The preliminary diagnosis is a communication failure. Have any forum members used these two systems? Has this kind of issue occurred? How was it resolved? ! !
For communication via what protocol, ensure proper grounding
Our DCS is from Yokogawa, and the IPS is from Conixion. The PV values and trip interlock alarm values of the DCS are obtained by the IPS using MODBUS communication. The values transmitted by the IPS need to have their Gain and Bias configured in the DCS in order to be displayed correctly; otherwise, discrepancies will occur.
Are the data read by DCS normal? If everything is normal, check the range of the DCS intermediate variables and the settings for alarm values. If the communication parameters are not checked properly. The default range for intermediate variables in Allen-Bradley M6 is 0-100.
Normally, the interlock value at the SIS point is higher than the alarm value of the DCS. SIS can transmit data to the DCS for display; under normal circumstances, the DCS should also have corresponding measurement points, allowing for a comparison between the two. If a communication failure occurs, the cause of the failure should be checked and resolved. Before eliminating the fault, it is possible to suspend SIS communication with DCS