# SYSTEMAIR\_ACCESS\_CONTROL ## `SYSTEMAIR_ACCESS_CONTROL` (FB) `FUNCTION_BLOCK` SYSTEMAIR\_ACCESS\_CONTROL ### Representation
InOut: | Scope | Name | Type | Initial | Comment | | ----------- | -------------------- | --------------------------------------------- | ------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | | Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) | | Input | `byUnitId` | `BYTE` | 0 | Device address | | Input | `xUpdateActual` | `BOOL` | FALSE |

Update of actual values (on every rising edge
)

| | Input | `xUpdateSetp` | `BOOL` | FALSE |

Update of setpoints (on every rising edge
)

| | Input | `eExternalCon` | SYSTEMAIR\_ACCESS\_CONTROL\_EXTERNAL\_CONTROL | SYSTEMAIR\_ACCESS\_CONTROL\_EXTERNAL\_CONTROL.NO\_EXTERNAL\_CONTROL | External control of the device — default | | Input | `eTempConMode` | SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE | SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE.SUPPLY\_AIR | Type of temperature control of the device — default | | Input | `eFanConMode` | SYSTEMAIR\_ACCESS\_CONTROL\_FAN\_CONT\_MODE | SYSTEMAIR\_ACCESS\_CONTROL\_FAN\_CONT\_MODE.FLOW | Type of control of the device fans — default | | Input | `rSpTempSupplyAir` | `REAL` | 21.0 |

Supply air setpoint temperature in degrees Celsius when eTempConMode =
SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE.SUPPLY\_AIR

| | Input | `rSpTempExtrAir` | `REAL` | 22.0 |

Extract air setpoint temperature in degrees Celsius when eTempConMode =
SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE.EXTRACT\_AIR\_CASCADE

| | Input | `rSpTempRoom` | `REAL` | 22.0 |

Room setpoint temperature in degrees Celsius when eTempConMode =
SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE.ROOM\_CASCADE

| | Input | `xAckAlarmsDev` | `BOOL` | FALSE | Acknowledgement of all alarms (TRUE = active) | | Input | `xResAlarmSICDev` | `BOOL` | FALSE |

Reset of the service interval counter alarm (TRUE
= active)

| | Input | `xResError` | `BOOL` | FALSE |

Reinitialization of the output eErrorCodeCom in the
fault-free state (on each rising edge)

| | Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device | | Output | `eUnitModeFb` | SYSTEMAIR\_ACCESS\_CONTROL\_OP\_MODE\_FB | | Operating mode of the device — feedback | | Output | `eUnitTrigFb` | SYSTEMAIR\_ACCESS\_CONTROL\_TRIG\_FB | |

Cause of the current operating mode of the device —
feedback

| | Output | `eExternalConFB` | SYSTEMAIR\_ACCESS\_CONTROL\_EXTERNAL\_CONTROL | | State of the external control of the device — feedback | | Output | `eTempConModeFB` | SYSTEMAIR\_ACCESS\_CONTROL\_TEMP\_CONTR\_MODE | |

Current type of temperature control of the device —
feedback

| | Output | `eFanConModeFB` | SYSTEMAIR\_ACCESS\_CONTROL\_FAN\_CONT\_MODE | |

Current type of control of the device fans —
feedback

| | Output | `eSupAirFanMode` | SYSTEMAIR\_ACCESS\_CONTROL\_FAN\_MODE | | Operating mode of the supply air fan | | Output | `eExtAirFanMode` | SYSTEMAIR\_ACCESS\_CONTROL\_FAN\_MODE | | Operating mode of the extract air fan | | Output | `rTempOda` | `REAL` | | Current outdoor temperature in degrees Celsius | | Output | `rTempIntakeAir` | `REAL` | | Current outdoor air temperature in degrees Celsius | | Output | `rTempSupplyAir` | `REAL` | | Current supply air temperature in degrees Celsius | | Output | `rTempExhaustAir` | `REAL` | | Current exhaust air temperature in degrees Celsius | | Output | `rTempExtractAir` | `REAL` | | Current extract air temperature in degrees Celsius | | Output | `rSupplyAirPres` | `REAL` | | Current pressure in the supply air in Pa | | Output | `rExtractAirPres` | `REAL` | | Current pressure in the extract air in Pa | | Output | `rSupplyAirFlow` | `REAL` | | Current volume flow in the supply air | | Output | `rExtractAirFlow` | `REAL` | | Current volume flow in the extract air | | Output | `rExtractAirCO2` | `REAL` | | Current CO2 content in the extract air / in the room in ppm | | Output | `rExtractAirHum` | `REAL` | |

Current relative humidity in the extract air / in the room in
percent

| | Output | `rFilterSupAir` | `REAL` | | Differential pressure - filter - supply air in Pa | | Output | `rFilterExtAir` | `REAL` | | Differential pressure - filter - extract air in Pa | | Output | `rTempAveragRoom` | `REAL` | |

Temperature - average of all four room temperature sensors in
degrees Celsius

| | Output | `rActiveSeq` | `REAL` | | Number of the active sequence (1 … 10) | | Output | `arrContSigSeq` | `ARRAY` \[1 .. 10] `OF` `REAL` | | Control signal of the individual sequences (1 … 10) | | Output | `rSupAirFanCon` | `REAL` | | Control signal for the supply air fan in percent | | Output | `rExtAirFanCon` | `REAL` | | Control signal for the extract air fan in percent | | Output | `rSpTempSupplyAirFb` | `REAL` | |

Current setpoint of the supply air temperature in degrees Celsius —
feedback

| | Output | `rSpSupAirFan` | `REAL` | |

Current setpoint for the supply air fan as pressure /
volume flow

| | Output | `rSpExtAirFan` | `REAL` | |

Current setpoint for the extract air fan as pressure /
volume flow

| | Output | `rSFP` | `REAL` | | Specific fan power in Ws/m3 | | Output | `rSupAirFanUpM` | `REAL` | | Number of revolutions of the supply air fan per minute | | Output | `rExtAirFanUpM` | `REAL` | | Number of revolutions of the extract air fan per minute | | Output | `rPosDamper_1` | `REAL` | | Current position of damper 1 in percent | | Output | `rPosDamper_2` | `REAL` | | Current position of damper 2 in percent | | Output | `rPosDamper_3` | `REAL` | | Current position of damper 3 in percent | | Output | `rPosDamper_4` | `REAL` | | Current position of damper 4 in percent | | Output | `rPosDamper_5` | `REAL` | | Current position of damper 5 in percent | | Output | `rSpSupAirCool` | `REAL` | | Setpoint - supply air temperature in cooling mode in degrees Celsius | | Output | `rSpSupAirHeat` | `REAL` | | Setpoint - supply air temperature in heating mode in degrees Celsius | | Output | `rSpDehum` | `REAL` | | Setpoint - dehumidification in percent relative humidity | | Output | `rSpHum` | `REAL` | | Setpoint - humidification in percent relative humidity | | Output | `eHumConMode` | SYSTEMAIR\_ACCESS\_CONTROL\_HUM\_MODE | | Current operating mode during humidification / dehumidification | | Output | `xErrorDevice_A` | `BOOL` | |

Alarm output - unacknowledged fault messages - Alarm A (
TRUE = fault active)

| | Output | `xErrorDevice_B` | `BOOL` | |

Alarm output - unacknowledged fault messages - Alarm B (
TRUE = fault active)

| | Output | `xErrorDevice_C` | `BOOL` | |

Alarm output - unacknowledged fault messages - Alarm C (
TRUE = fault active)

| | Output | `xFilterSupAir` | `BOOL` | |

Filter maintenance indicator - supply air (TRUE = maintenance required
)

| | Output | `xFilterExtAir` | `BOOL` | |

Filter maintenance indicator - extract air (TRUE = maintenance required
)

| | Output | `xFireAlarm` | `BOOL` | | Fire alarm (TRUE = alarm active) | | Output | `xSmokeAlarm` | `BOOL` | | Smoke alarm (TRUE = alarm active) | | Output | `xAlarm` | `BOOL` | FALSE | Collective fault (TRUE = fault) | | Output | `xAlarmCom` | `BOOL` | FALSE | Collective fault - communication (TRUE = fault) | | Output | `eErrorCodeCom` | ModbusErrorCode | | Error code - communication (0 = no error) | | Output | `xBusy` | `BOOL` | | Communication indicator (TRUE = communication) | | Input Const | `diAdrOffset` | `DINT` | 0 |

Offset for calculating the Modbus addresses (from the Modbus
registers) (permitted range: -1, 0, +1)

| | Input Const | `tTimeUpdateSetp` | `TIME` | TIME#45s0ms |

Update interval for the processes influenced by the input
xUpdateSetp influenced

| | Input Const | `tTimeUpdateActual` | `TIME` | TIME#10s0ms |

Update interval for the processes influenced by the input
xUpdateActual influenced

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