AVERAGE: Average of 8 real values
The AVERAGE (FC393) block calculates the average of 8 real values. The calculation only accounts for the valid input signals and their respective weighting.
More than 8 input signals are processed by cascading the block.
Functionality
The block calculates the weighted arithmetic mean [Out] from max. 8 inputs [In1]...[In8] by accounting for the weighting [Wght1]...[Wght8] and "Enable input" 1...8 [EnIn1]...[EnIn8].
All unlocked values are accounted for when calculating the average (e.g., [EnIn1] = 1 (Yes). As a result, the average [Out] is derived from all unlocked input values multiplied by their weighting.
The output "Weighting total" [WghtTot] supplies the sum of all weightings for all unlocked inputs.
Inputs
Pin | E | Description | |
In1 | pa | Input 1. Input 1 for calculating the average. | |
Wght1 | pa | Weighting 1. Parameter to weight input 1 in proportion to the other inputs. | |
0.0 | Default value. This Input will not be calculated. | ||
< 0 | Negative weighting is replaced by the absolute value for calculation purposes. The absolute value is reread to the input. | ||
EnIn1 | pa | Enable input 1. Switch to exclude input 1 from calculation of average (e.g. faulty input signal). If the input is used as a parameter (not wired), [EnIn] = 1 (Yes) must be set (e.g. no error supervision). | |
1 (Yes) | Input 1 is enabled. | ||
0 (No) | Input 1 is not used (Default value). | ||
In2 | pa | Input 2. | |
Wght2 | pa | Weighting 2. | |
EnIn2 | pa | Enable input 2. | |
In3..8 | pa | Input 3..8. Make input visible first. | |
Wght3..8 | pa | Weighting 3..8. Make input visible first. | |
EnIn3..8 | pa | Enable input 3..8. | |
Outputs
Pin | E | Description |
Out | a | Output. Weighted average value for all unlocked input values. |
WghtTot | a | Weighting total. Sum of the weighted values for all unlocked input values. |
Input values
Pin | Description | Data type | Default value | E.g. Engineering unit or Text group | Min. | Max. |
In1..In8 | Input 1..8 | Real | 1.0 |
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Wght1..Wght8 | Weighting 1..8 | Real | 0.0 |
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EnIn1..EnIn8 | Enable input 1..8 | Boolean | 0 (No) | No, Yes |
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Output values
Pin | Description | Data type | Default value | E.g. Engineering unit or Text group | Min. | Max. |
Out | Output. | Real | 0.0 |
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WghtTot | Weighting total. | Real | 0.0 |
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Application
Normally, the block is set for averaging the measured values.
As not all input values are weighted in proportion, weighting factors can be selected:
- Average of several room temperatures including room size weighting.
- Average of parallel sensors to increase measuring accuracy in large air ducts.
- Average for parallel sensors to increase availability.
Cascading several AVERAGE blocks to calculate average values from more than 8 input values is possible.
Process response
Standard (see General rules and information).
Troubleshooting
Negative weighting of [Whgt1...8] (by parameterization) are replaced by their absolute value for calculation purposes. The replacement values are reread to the inputs.
If the sum of all weightings [Wght1...8] of valid inputs is 0, then [Out] = 0.
If all inputs [In1]...[In8] are invalid, i.e., all inputs [EnIn1]...[EnIn8] = 0 (No), then [Out] = 0.