Standard Operations
5.15 Formula editor for output and relay card
Formulas can be used as additional signal source for output and relay cards (DIN rail and expansion cards). Each channel of the output or relay card can be used to run a formula. The result of a formula can be used the same way like real measured values.
By using formulas, “virtual measurements” can be created (for example average values from measured values of multiple probes). The virtual measured value is calculated from the measured readings of other probes.
5.15.1 Add a formula
To add a formula:
1.Select SYSTEM SETUP,
a.for an output card continue with OUTPUT SETUP, mA OUTPUT INT/EXT,
OUTPUT 1-4, SELECT SOURCE, SET FORMULA.
b.for a relay card continue with RELAY, RELAY INT/EXT, RELAY
2.The main menu of the formula editor is displayed (Figure 49). Tap on the text fields to edit the Name, Location, Unit, Parameter and Formula.
| Figure 49 Main menu of the formula editor | |
| Table 21 Formula settings | |
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Function | Description | |
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Name | Enter a reference name for identification in display views and log files (Maximum of 16 | |
characters). | ||
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Location | Enter an additional location information for unique identification (Maximum of 16 characters) | |
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Unit | Enter a virtual measurement unit (Maximum of 6 characters). | |
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Parameter | Enter a virtual measurement parameter (Maximum of 6 characters). | |
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Formula | Enter a formula, which calculates the virtual measurement value. The formula can use | |
letters A, B, C as shortcuts for other measurement values (Table 23, Table 24, Table 25). | ||
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Definition for letters A, B, C | Lists the existing assignments (for other measurement values). | |
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Add (Tag) | Creates a new letter (A, B, C) as a place holder for another new measurement value. | |
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