Industry Sector, IA&DT
The curves should be displayed colored as continuous lines or as a series of dots. Color coding can be selected as required. The number of curves for each curve display field should be limited to six. The colors of the curves should be easily distinguishable from each other.
To implement the curve course, the following directions are recommended:
–From right to left: more recent values to the right, older values to the left
–From top to bottom: more recent values on top, older values on the bottom
The deciding factor in this case is whether a display time span that is as large as possible (from left to right) or a value resolution that is as high as possible (from top to bottom) is needed.
When curves with a prehistory are displayed, the curve course is updated; the entire curve shifts in the direction of the past (refer to Figure 2). If there is a shift with each new entry, the entire curve display field can be used to display the prehistory, and the operator can follow the display well since the curve is shifted only a little. If needed, it should be possible to stop the update.
For labeling the value axis, 1, 2 and 5 should be used for scale marks as well as their decade multiple. The value axis can be scaled in units or in percent. Table 1 shows where the value axis should be located. Also, a display with two value axes can be useful; in this case, the percent axis for all curves is displayed to the left, and the display of the values of a curve in units to the right. The time axis should always be labeled as shown in Table 1.
To display time spans [2] offers the time spans and scale marks recommended in Table 2. It was taken into account here that if there is a change to another display time span, the same point in time can be located again.
Table 2: Recommended Display Time Spans [2]
Primary Task | Preassigned Display | Updating Cycle (only | Scale Mark | |
| Time Spans | for prehistory) |
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Commissioning | 5 min | 1 s | 1 min | |
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Process Control | 15 min | 1 s | 5 min | |
or Analysis |
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30 min | 2 s | 5 min | ||
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| 2 h | 8 s | 30 min | |
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| 8 h | 32 s | 1 h | |
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| 24 h | 96 s | 4 h | |
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| 4 days | 384 s | 12 h | |
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Analysis | 7 days | - | 1 day | |
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| 30 days | - | 7 days | |
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| 90 days | - | 15 days | |
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| 360 days | - | 90 days | |
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SCE Training Curriculum | Page 7 of 42 | To be used only at Educational and R&D Facilities |
PA Module |
| Unrestricted / © Siemens AG 2013. All Rights Reserved |
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