Clock synchronization issues in instrument control systems
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Discussion is welcome: 1. The purpose of clock synchronization is to ensure consistency in time-stamped data within the DCS system as well as between it and other systems. Is it necessary for both absolute time and relative time to be consistent? 2. In practical applications, is it necessary to set up clock synchronization for third-party devices that do not require data labeling?
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1. The fundamental purpose of clock synchronization is indeed to maintain consistency in data time stamps, thereby facilitating accurate recording of events and fault analysis. Generally, absolute time (i.e., real-world time) synchronization is necessary, as it relates to the system’s interaction with the outside world, such as logging and data exchange with other systems. Relative time synchronization (i.e., the time difference between various devices within a system) is also important, especially in scenarios that require high-precision control or data integration. 2. For third-party devices that do not require timing information for their data, whether clock synchronization is necessary depends on their role and importance within the entire control system. If the operation of these devices has no direct impact on other parts of the system, or if they do not share critical functions with other devices in the system, clock synchronization may not be necessary. However, if there is a possibility in the future to need time data from these devices or to integrate them more closely with the main system, it is recommended to implement clock synchronization. .
Book titled “Chemical Process DCS Technology and Operation (2nd Edition)”.
1. The representation of relative time places more emphasis on the sequence and relative relationships of time, and is suitable for describing the order in which events occur and the chronological sequence of times. 2. Not needed.
Book titled “Operation and Maintenance of DCS Control Systems”.
1. As long as the relative time is consistent. Relative time is based on a certain event as a reference point, and it is defined in relation to specific events. 2. For third-party devices that do not require data labeling, clock synchronization is not necessary. Thank you for sharing, 315034589@qq.com.
Could it be sent to 1530826281@qq.com? Thank you. 1. The basic scanning cycle of a DCS is generally between 0.5s and 1.0s, while the cycle of an SIS system is usually in the millisecond range; therefore, during actual synchronization, there is typically a difference of 3s to 5s. Absolute timing consistency is not required. 2. No setting is required.