Regarding PID diagram control systems
Thread Content
What does this gauge with a K mean?
It might be a ratio; this depends on the process. Which is the key parameter, hydrogen or C4?
Based on the understanding of the given diagram, it should be a proportional control system.
This post was last edited by Ku Liang Zhi Le on 2019-5-16 08:41. It is a dual closed-loop ratio control system: the C4 flow rate is multiplied by a coefficient K, and the result is sent to the H2 controller as a setpoint, thereby establishing a proportional relationship between C4 and H2. The representation in this figure is not standard enough; the multiplication coefficients are implemented within the DCS, so it should be a circle enclosed in a box. Above the multiplied symbol enclosed in a box, FY should be indicated, with an × mark placed next to the box. The standard specifies that only circles indicate conventional instruments. Obviously, it’s wrong.