Regarding the instrument range issue
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What will the DCS display show if the range is increased after making changes to the DCS, while the field instruments have not had their ranges adjusted? What will happen if the scale on site is increased or decreased, but the DCS does not adjust its range? How can it be explained in a way that is easy to understand?
Looking at it (+﹏+)~ I’m confused; not knowing the situation means I must be talking nonsense. This system can only be modified based on the training provided by various manufacturers or according to the relevant installation instructions, and only those with the appropriate permissions can make changes. One is responsible for this. It’s best for those who aren’t trained not to take risks; this isn’t something that anyone can modify. With all due respect, this is just for your reference.
For example, if the temperature shown on site is 50°C, and the original range of the system and instruments is 0–100°C, then 50°C will be displayed on the backend. If you change the system’s range to 0–200°C, the temperature on site remains 50°C, but the backend now shows 100°C. Therefore, if the system’s range is changed, the range of the instruments must also be changed accordingly; otherwise, the data on the backend will become inconsistent
Display at enlarged scale! It’s not a matter of changing the range; rather, the range during debugging was smaller than the effective range. I didn’t notice it at the time and only realized it during the debugging process.
The range cannot be changed arbitrarily; if a change is necessary, it must be calibrated using standard measuring instruments before it can be used.
The scene remains unchanged; the DCS becomes larger, and the display also gets larger. The DCS remains unchanged; the site size increases, while the DCS size decreases
The field instrument uses 4-20ma for percentage data transmission. The 4-20ma received by DCS is also a percentage value. When converting to engineering quantities, the data range represented by 0-100% must be the same. If the ranges of the field instruments and the DCS are different, it is as if the same percentage (x%) is being applied to different values (y).
Don’t worry about it; both sides need to be changed simultaneously to maintain consistency
This question is weird! For example, if the temperature at the site is 0~500°C, it should also be 0~500°C on the DCS side; why change it? ?