# CrossVentilation\_Sulzer
## `CrossVentilation_Sulzer` (FB)
FUNCTION\_BLOCK CrossVentilation\_Sulzer
### Short description
> Control of cross-ventilation using window elements via four separately adjustable characteristic curves\
> \
> Curve 1: Opening time depending on outside temperature\
> Curve 2: Degree of opening depending on outside temperature\
> Curve 3: Degree of opening depending on wind speed\
> Curve 4: Waiting time depending on outside temperature\
> \
> Typical application: Control of cross-ventilation by the room CO2 actual value
### Representation
### Interfaces
#### Inputs
| Name | Data type | Value range | Initial value | Function |
| ------------------------ | --------- | ----------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| *xStartCrossVentilation* | BOOL | | FALSE | Start of cross-ventilation (on each rising edge) |
| *xAbortCrossVentilation* | BOOL | | FALSE | Abort cross-ventilation (on each rising edge) |
| *xEn\_WT* | BOOL | | FALSE | Enable / disable waiting time (TRUE = enabled) |
| *xEnComplete\_OT* | BOOL | | FALSE | Enable / disable the input ‘xComplete\_OT’ (FALSE = disabled) (\_OT = Opening Time) |
| *xComplete\_OT* | BOOL | | FALSE | Enable / disable manual abort of the opening duration (on each rising edge, if xEnComplete\_OT = TRUE) (e.g. abort via CO2 level after the opening duration has elapsed) |
| *rOutsideTemp* | REAL | | 0.0 | Outside temperature |
| *rOutsideWindSpeed* | REAL | | 0.0 | Wind speed |
| *xResError* | BOOL | | FALSE | Reset of the outputs ‘xError’ and ‘sErrorCode’ (on each rising edge) |
| *xValidData\_OT* | BOOL | | FALSE | Validity of the data of the curve ‘Opening Time - Outside Temperature’ (\_OT = Opening Time) (TRUE = valid) |
| *xValidData\_WDOO\_OT* | BOOL | | FALSE | Validity of the data of the curve ‘Window Degree Of Opening - Outside Temperature’ (\_WDOO = Windows Degree Of Opening, \_OT = OutsideTemp) (TRUE = valid) |
| *xValidData\_WDOO\_WS* | BOOL | | FALSE | Validity of the data of the curve ‘Window Degree Of Opening - Wind Speed’ (\_WDOO = Windows Degree Of Opening, \_WS = Wind Speed) (TRUE = valid) |
| *xValidData\_WT* | BOOL | | FALSE | Validity of the data of the curve ‘Waiting Time - Outside Temperature’ (\_WT = Waiting Time) (TRUE = valid) |
#### Inputs and outputs
| Name | Data type | Value range | Initial value | Function |
| ------------------ | ------------------- | ----------- | ------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- |
| *arData\_OT* | stCurve\_Real\_Time | | | Array with the support points for the curve ‘Opening Time - Outside Temperature’ (\_OT = Opening Time) |
| *arData\_WDOO\_OT* | stCurve\_Real\_Real | | | Array with the support points for the curve ‘Window Degree Of Opening - Outside Temperature’ (\_WDOO = Windows Degree Of Opening, \_OT = OutsideTemp) |
| *arData\_WDOO\_WS* | stCurve\_Real\_Real | | | Array with the support points for the curve ‘Window Degree Of Opening - Wind Speed’ (\_WDOO = Windows Degree Of Opening, \_WS = Wind Speed) |
| *arData\_WT* | stCurve\_Real\_Time | | | Array with the support points for the curve ‘Waiting Time - Outside Temperature’ (\_WT = Waiting Time) |
#### Outputs
| Name | Data type | Value range | Initial value | Function |
| ------------------------ | --------- | ----------- | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ |
| *tTimeCurve\_OT* | TIME | | T#0s | Current opening time duration from the curve (\_OT = Opening Time) |
| *tRemainingTime\_OT* | TIME | | T#0s | Remaining time of the active opening time duration (\_OT = Opening Time) |
| *xActive\_OT* | BOOL | | FALSE | Feedback - Active opening time duration (TRUE = active) (\_OT = Opening Time) |
| *rDegreeCurve\_WDOO\_OT* | REAL | | 0.0 | Current window degree of opening \[ % ] depending on outside temperature from the curve (\_WDOO = Windows Degree Of Opening, \_OT = OutsideTemp) |
| *rDegreeCurve\_WDOO\_WS* | REAL | | 0.0 | Current window degree of opening \[ % ] depending on wind speed from the curve (\_WDOO = Windows Degree Of Opening, \_WS = Wind Speed) |
| *rDegree\_WDOO* | REAL | | 0.0 | Current window degree of opening \[ % ] (\_WDOO = Windows Degree Of Opening) |
| *xActive\_WDOO* | BOOL | | FALSE | Feedback - Active window opening (TRUE = active) (\_WDOO = Windows Degree Of Opening) |
| *tTimeCurve\_WT* | TIME | | T#0s | Current waiting time from the curve (\_WT = Waiting Time) |
| *tRemainingTime\_WT* | TIME | | T#0s | Remaining time of the active waiting time (\_WT = Waiting Time) |
| *xActive\_WT* | BOOL | | FALSE | Feedback - Active waiting time (TRUE = active) (\_WT = Waiting Time) |
| *xError* | BOOL | | FALSE | Error state (FALSE = no error, TRUE = error) |
| *sErrorCode* | STRING | | ‘’ | String with the numbers of the active errors |
#### Setpoints / parameters
| Name | Data type | Value range | Initial value | Function |
| --------------------- | --------- | ----------- | ------------- | ------------------------------------------------------------------------------- |
| **rOutsideTempLimit** | REAL | | -15 | Outside temperature threshold, below which no window opening will be initiated. |
### Function description
#### Characteristic curves
The total of four freely adjustable characteristic curves (each with 10 support points, FB ‘Curve\_10XY\_Real’ or FB ‘Curve\_10XY\_Real\_Time’)\
are connected to the associated data inputs (arData\_XX), as well as the outputs of the curves that signal the validity\
of the data (xValidData\_XX).\
The assignment of the characteristic curves to the inputs is fixed as follows:
1. Index \_OT (Opening Time): Curve ‘Opening time depending on outside temperature’
2. Index \_WDOO\_OT (\_WDOO = Windows Degree Of Opening, \_OT = Outside Temp): Curve ‘Degree of opening depending on outside temperature’
3. Index \_WDOO\_WS (\_WDOO = Windows Degree Of Opening, \_WS = Wind Speed): Curve ‘Degree of opening depending on outside wind speed”
4. Index \_WT (Waiting Time): Curve ‘Waiting time depending on outside temperature’
If an input value (= X-value) outside the range specified by support points 1 and 10 is passed to a curve, the Y-value of the nearest support point is returned (example: support point 1 (1, 10), support point 10 (10, 100), X-value = -5 — Y-value = 10)
#### Procedure
Cross-ventilation is started with a rising edge at the input ‘xStartCrossVentilation’. The opening time duration is calculated from curve 1.\
The degree of opening is determined and output from curves 2 and 3. After the window opening is completed, the waiting time calculated from curve 4\
is started, which temporarily prevents another cross-ventilation.
#### Start of cross-ventilation
Cross-ventilation is started with a rising edge at the input ‘xStartCrossVentilation’ if all of the following conditions are met:
1. The waiting time is not active (xActive\_WT = FALSE)
2. The opening time is not active (xActive\_OT = FALSE)
3. All four curves contain valid data (xValidData\_XX = TRUE)
4. The outside temperature exceeds the absolute minimum limit (rOutsideTemp > rOutsideTempLimit)
#### Opening duration
After successful start of cross-ventilation, the opening time duration is calculated once from curve 1 depending on the current\
outside temperature. During the opening time duration, the status indicator ‘xActive\_OT’ is active and the remaining time duration is output on the output ‘tRemainingTime\_OT’.
#### Abort
The active cross-ventilation can be aborted at any time by a rising edge at the input ‘xAbortCrossVentilation’.
#### Degree of opening
After successful start of cross-ventilation, the degree of opening is determined once from the two curves 2 and 3 depending on the current outside temperature\
and the current outside wind speed:\
\
Variable Z = ((Value from curve 2) X (Value from curve 3)) / 100\
The variable Z is then compared with fixed predefined range limits and the degree of opening assigned to the respective range is output:\
\
0 <= Z < 15: Degree of opening = 0%\
15 <= Z < 25: Degree of opening = 25%\
25 <= Z < 50: Degree of opening = 50%\
50 <= Z < 75: Degree of opening = 75%\
Z > 75 : Degree of opening = 100%\
\
The determined degree of opening is output at the output ‘rDegree\_WDOO’, the output ‘xActive\_WDOO’ signals an active window opening (= TRUE).
#### Waiting time
Directly after the end of the opening duration, a possible waiting time until the next activation of cross-ventilation begins. For this, the waiting time duration must generally be enabled (xEn\_WT = TRUE). At the start of the waiting time, the duration is determined once from curve 4 depending on the outside temperature.\
During the active waiting time the status indicator ‘xActive\_WT’ is active and the remaining time duration is output at the output ‘tRemainingTime\_WT’.\
The waiting time ends when the duration expires or when the waiting time is disabled (xEn\_WT = FALSE).
#### End of opening time
The opening time ends immediately when the duration elapses (xEnComplete\_OT = FALSE).\
The opening time ends after the duration elapses (xEnComplete\_OT = TRUE) if a rising edge is detected at the input ‘xComplete\_OT’.\
This serves to extend the opening duration until an acceptable CO2 level is reached.
#### Blocking cross-ventilation via outside temperature
Cross-ventilation is only started if the current outside temperature at the start time exceeds the adjustable limit ‘rOutsideTempLimit’.
#### Input ‘xResError’
Each rising edge on this input resets the outputs ‘xError’ and ‘sErrorCode’ to their respective no-error state.
#### Output ‘xError’
The output is active (= TRUE) if at least one error has been detected (‘sErrorCode <> ‘‘).
#### Output ‘sErrorCode’
This output signals the current error status. An empty string ‘’ indicates that no error is present.\
Currently the following error states are defined:\
‘1’: xValidData\_OT = FALSE (Curve 1 without valid data)\
‘2’: xValidData\_WDOO\_OT = FALSE (Curve 2 without valid data)\
‘3’: xValidData\_WDOO\_WS = FALSE (Curve 3 without valid data)\
‘4’: xValidData\_WT = FALSE (Curve 4 without valid data)
#### This function block can be applied as follows:
The output ‘xActive\_WDOO’ (= TRUE) signals the request to open the windows for cross-ventilation, the output ‘rDegree\_WDOO’ the window opening degree in the range 0.0 - 100.0% (0.0% = closed).\
This function block can be applied as follows:
### CODESYS
InOut:
| Scope | Name | Type | Initial |
| ----------- | ------------------------ | ------------------------------ | -------- |
| Input | `xStartCrossVentilation` | `BOOL` | FALSE |
| Input | `xAbortCrossVentilation` | `BOOL` | FALSE |
| Input | `xEn_WT` | `BOOL` | TRUE |
| Input | `xEnComplete_OT` | `BOOL` | FALSE |
| Input | `xComplete_OT` | `BOOL` | FALSE |
| Input | `rOutsideTemp` | `REAL` | 0.0 |
| Input | `rOutsideWindSpeed` | `REAL` | 0.0 |
| Input | `xResError` | `BOOL` | FALSE |
| Input | `xValidData_OT` | `BOOL` | FALSE |
| Input | `xValidData_WDOO_OT` | `BOOL` | FALSE |
| Input | `xValidData_WDOO_WS` | `BOOL` | FALSE |
| Input | `xValidData_WT` | `BOOL` | FALSE |
| Input | `arData_OT` | POINTER TO stCurve\_Real\_Time | |
| Input | `arData_WDOO_OT` | POINTER TO stCurve\_Real\_Real | |
| Input | `arData_WDOO_WS` | POINTER TO stCurve\_Real\_Real | |
| Input | `arData_WT` | POINTER TO stCurve\_Real\_Time | |
| Output | `tTimeCurve_OT` | `TIME` | TIME#0ms |
| Output | `tRemainingTime_OT` | `TIME` | TIME#0ms |
| Output | `xActive_OT` | `BOOL` | FALSE |
| Output | `rDegreeCurve_WDOO_OT` | `REAL` | 0.0 |
| Output | `rDegreeCurve_WDOO_WS` | `REAL` | 0.0 |
| Output | `rDegree_WDOO` | `REAL` | 0.0 |
| Output | `xActive_WDOO` | `BOOL` | FALSE |
| Output | `tTimeCurve_WT` | `TIME` | TIME#0ms |
| Output | `tRemainingTime_WT` | `TIME` | TIME#0ms |
| Output | `xActive_WT` | `BOOL` | FALSE |
| Output | `xError` | `BOOL` | FALSE |
| Output | `sErrorCode` | `STRING` | ‘’ |
| Input Const | `rOutsideTempLimit` | `REAL` | -15.0 |
Methods:
> mCalculateCurveSectionValue\_Real\_Real
> mCalculateCurveSectionValue\_Real\_Time
> mCalculateCurveValue\_Real\_Real
> mCalculateCurveValue\_Real\_Time
> mResData
Structure:
* mCalculateCurveSectionValue\_Real\_Real (Method)
* mCalculateCurveSectionValue\_Real\_Time (Method)
* mCalculateCurveValue\_Real\_Real (Method)
* mCalculateCurveValue\_Real\_Time (Method)
* mResData (Method)
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