> For the complete documentation index, see [llms.txt](https://support.powerio.com/hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.powerio.com/hub/codesys-hvac/en/hvac-modbus-library/functionblocks/systemair/systemair_save_control.md). # SYSTEMAIR\_SAVE\_CONTROL ## `SYSTEMAIR_SAVE_CONTROL` (FB) `FUNCTION_BLOCK` SYSTEMAIR\_SAVE\_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 | `eOpMode` | SYSTEMAIR\_SAVE\_CONTROL\_OP\_MODE | SYSTEMAIR\_SAVE\_CONTROL\_OP\_MODE.AUTO | Operating mode of the device — preset | | Input | `arwSpFan_Percent` | `ARRAY` \[1 .. 10] `OF` `WORD` | \[16, 16, 16, 16, 16, 16, 16, 16, 16, 16] |

Setpoints (percent) of the fans in the individual fan stages (MIN, LOW, NORMAL, HIGH, MAX)
arwSpFan\_Percent\[1] = Setpoint - supply fan at stage MIN (range: 16 … 100)
arwSpFan\_Percent\[2] = Setpoint - exhaust fan at stage MIN (range: 16 … 100)
arwSpFan\_Percent\[3] = Setpoint - supply fan at stage LOW (range: 16 … 100)
arwSpFan\_Percent\[4] = Setpoint - exhaust fan at stage LOW (range: 16 … 100)
arwSpFan\_Percent\[5] = Setpoint - supply fan at stage NORMAL (range: 16 … 100)
arwSpFan\_Percent\[6] = Setpoint - exhaust fan at stage NORMAL (range: 16 … 100)
arwSpFan\_Percent\[7] = Setpoint - supply fan at stage HIGH (range: 16 … 100)
arwSpFan\_Percent\[8] = Setpoint - exhaust fan at stage HIGH (range: 16 … 100)
arwSpFan\_Percent\[9] = Setpoint - supply fan at stage MAX (range: 16 … 100)
arwSpFan\_Percent\[10] = Setpoint - exhaust fan at stage MAX (range: 16 … 100)

| | Input | `arwSpFan_UPM` | `ARRAY` \[1 .. 10] `OF` `WORD` | \[500, 500, 500, 500, 500, 500, 500, 500, 500, 500] |

Setpoints (RPM) of the fans in the individual fan stages (MIN, LOW, NORMAL, HIGH, MAX)
arwSpFan\_UPM\[1] = Setpoint - supply fan at stage MIN (range: 500 … 5000)
arwSpFan\_UPM\[2] = Setpoint - exhaust fan at stage MIN (range: 500 … 5000)
arwSpFan\_UPM\[3] = Setpoint - supply fan at stage LOW (range: 500 … 5000)
arwSpFan\_UPM\[4] = Setpoint - exhaust fan at stage LOW (range: 500 … 5000)
arwSpFan\_UPM\[5] = Setpoint - supply fan at stage NORMAL (range: 500 … 5000)
arwSpFan\_UPM\[6] = Setpoint - exhaust fan at stage NORMAL (range: 500 … 5000)
arwSpFan\_UPM\[7] = Setpoint - supply fan at stage HIGH (range: 500 … 5000)
arwSpFan\_UPM\[8] = Setpoint - exhaust fan at stage HIGH (range: 500 … 5000)
arwSpFan\_UPM\[9] = Setpoint - supply fan at stage MAX (range: 500 … 5000)
arwSpFan\_UPM\[10] = Setpoint - exhaust fan at stage MAX (range: 500 … 5000)

| | Input | `arwSpFan_Pressure` | `ARRAY` \[1 .. 10] `OF` `WORD` | \[0, 0, 0, 0, 0, 0, 0, 0, 0, 0] |

Setpoints (pressure) of the fans in the individual fan stages (MIN, LOW, NORMAL, HIGH, MAX)
arwSpFan\_Pressure\[1] = Setpoint - supply fan at stage MIN (range: unknown)
arwSpFan\_Pressure\[2] = Setpoint - exhaust fan at stage MIN (range: unknown)
arwSpFan\_Pressure\[3] = Setpoint - supply fan at stage LOW (range: unknown)
arwSpFan\_Pressure\[4] = Setpoint - exhaust fan at stage LOW (range: unknown)
arwSpFan\_Pressure\[5] = Setpoint - supply fan at stage NORMAL (range: unknown)
arwSpFan\_Pressure\[6] = Setpoint - exhaust fan at stage NORMAL (range: unknown)
arwSpFan\_Pressure\[7] = Setpoint - supply fan at stage HIGH (range: unknown)
arwSpFan\_Pressure\[8] = Setpoint - exhaust fan at stage HIGH (range: unknown)
arwSpFan\_Pressure\[9] = Setpoint - supply fan at stage MAX (range: unknown)
arwSpFan\_Pressure\[10] = Setpoint - exhaust fan at stage MAX (range: unknown)

| | Input | `arwSpFan_VolumeFlow` | `ARRAY` \[1 .. 10] `OF` `WORD` | \[0, 0, 0, 0, 0, 0, 0, 0, 0, 0] |

Setpoints (volume flow) of the fans in the individual fan stages (MIN, LOW, NORMAL, HIGH, MAX)
arwSpFan\_VolumeFlow\[1] = Setpoint - supply fan at stage MIN (range: unknown)
arwSpFan\_VolumeFlow\[2] = Setpoint - exhaust fan at stage MIN (range: unknown)
arwSpFan\_VolumeFlow\[3] = Setpoint - supply fan at stage LOW (range: unknown)
arwSpFan\_VolumeFlow\[4] = Setpoint - exhaust fan at stage LOW (range: unknown)
arwSpFan\_VolumeFlow\[5] = Setpoint - supply fan at stage NORMAL (range: unknown)
arwSpFan\_VolumeFlow\[6] = Setpoint - exhaust fan at stage NORMAL (range: unknown)
arwSpFan\_VolumeFlow\[7] = Setpoint - supply fan at stage HIGH (range: unknown)
arwSpFan\_VolumeFlow\[8] = Setpoint - exhaust fan at stage HIGH (range: unknown)
arwSpFan\_VolumeFlow\[9] = Setpoint - supply fan at stage MAX (range: unknown)
arwSpFan\_VolumeFlow\[10] = Setpoint - exhaust fan at stage MAX (range: unknown)

| | Input | `rSpTemp` | `REAL` | 22.0 |

Setpoint - temperature (supply air, exhaust air, room) (range:
12.0 - 30.0 degrees Celsius)

| | Input | `rSpSupplyTempMin` | `REAL` | 18.0 |

Minimum value - supply air temperature (range: 12.0 - 40.0 degrees
Celsius)

| | Input | `rSpSupplyTempMax` | `REAL` | 30.0 |

Maximum value - supply air temperature (range: 12.0 - 40.0 degrees
Celsius)

| | Input | `xFilterReset` | `BOOL` | FALSE | State of filter reset (TRUE = active) | | Input | `xResError` | `BOOL` | FALSE |

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

| | Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device | | Output | `eOpModeFb` | SYSTEMAIR\_SAVE\_CONTROL\_OP\_MODE\_FB | | Operating mode of the device — feedback | | Output | `xOperation` | `BOOL` | | Operating message of the device (TRUE = operation) | | Output | `rSpSupplyFan_Min` | `REAL` | |

Setpoint - supply fan at stage Minimum (percent,
RPM, pressure, volume flow)

| | Output | `rSpExhausFan_Min` | `REAL` | |

Setpoint - exhaust fan at stage Minimum (percent,
RPM, pressure, volume flow)

| | Output | `rSpSupplyFan_Low` | `REAL` | |

Setpoint - supply fan at stage Low (percent,
RPM, pressure, volume flow)

| | Output | `rSpExhausFan_Low` | `REAL` | |

Setpoint - exhaust fan at stage Low (percent,
RPM, pressure, volume flow)

| | Output | `rSpSupplyFan_Nor` | `REAL` | |

Setpoint - supply fan at stage Normal (percent,
RPM, pressure, volume flow)

| | Output | `rSpExhausFan_Nor` | `REAL` | |

Setpoint - exhaust fan at stage Normal (percent,
RPM, pressure, volume flow)

| | Output | `rSpSupplyFan_Hig` | `REAL` | |

Setpoint - supply fan at stage High (percent,
RPM, pressure, volume flow)

| | Output | `rSpExhausFan_Hig` | `REAL` | |

Setpoint - exhaust fan at stage High (percent,
RPM, pressure, volume flow)

| | Output | `rSpSupplyFan_Max` | `REAL` | |

Setpoint - supply fan at stage Maximum (percent,
RPM, pressure, volume flow)

| | Output | `rSpExhausFan_Max` | `REAL` | |

Setpoint - exhaust fan at stage Maximum (percent,
RPM, pressure, volume flow)

| | Output | `rRotSpeedSupFan` | `REAL` | |

Current speed of the supply fan in 1 / min (
tachometer signal, 0 - 5000)

| | Output | `rRotSpeedExhFan` | `REAL` | |

Current speed of the exhaust fan in 1 / min (
tachometer signal, 0 - 5000)

| | Output | `rSpSupplyAirTemp` | `REAL` | | Current supply air set temperature (12.0 - 30.0 degrees Celsius) | | Output | `rAntifreezeSig` | `REAL` | | Actual value - frost protection sensor (-40.0 - +80.0 degrees Celsius) | | Output | `rTempOda` | `REAL` | | Current outside temperature (-40.0 - +80.0 degrees Celsius) | | Output | `rSupplyAirTemp` | `REAL` | | Current supply air temperature (-40.0 - +80.0 degrees Celsius) | | Output | `rRoomTemp` | `REAL` | | Current room temperature (-40.0 - +80.0 degrees Celsius) | | Output | `rOverHeatTemp` | `REAL` | |

Current overheating temperature in the electric
post-heating coil (-40.0 - +80.0 degrees Celsius)

| | Output | `rExhaustAirTemp` | `REAL` | | Current exhaust air temperature (-40.0 - +80.0 degrees Celsius) | | Output | `rContSigHeatRec` | `REAL` | | Control signal - HRU or bypass (0 - 100%) | | Output | `rContSigReHeat` | `REAL` | | Control signal - post-heating coil (0 - 100%) | | Output | `xFilterMainten` | `BOOL` | |

Actual value - filter maintenance indicator (TRUE = maintenance required
)

| | Output | `xFireAlarm` | `BOOL` | | Actual value - fire alarm (smoke detector) (TRUE = alarm active) | | Output | `xErrorDevice_A` | `BOOL` | |

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

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

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

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

Alarm output - fault messages - Alarm C (TRUE = fault
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 | `eSpFanMode` | SYSTEMAIR\_SAVE\_CONTROL\_SP\_FAN\_MODE | SYSTEMAIR\_SAVE\_CONTROL\_SP\_FAN\_MODE.PERCENT |

Operating mode for the fan setpoints

By selecting this operating mode, the array is defined that is monitored for changes in the setpoints.
Example: eSpFanMode = SYSTEMAIR\_SAVE\_CONTROL\_SP\_FAN\_MODE.PERCENT
The array arwSpFan\_Percent is monitored for changes and transmitted if necessary.

| | Input Const | `eExhaustAirFanLevel` | SYSTEMAIR\_SAVE\_CONTROL\_EXHAUST\_AIR\_FAN\_LEVEL | SYSTEMAIR\_SAVE\_CONTROL\_EXHAUST\_AIR\_FAN\_LEVEL.NORMAL | Fan stage of the exhaust fan in manual mode | | Input Const | `eSupplyAirFanLevel` | SYSTEMAIR\_SAVE\_CONTROL\_SUPPLY\_AIR\_FAN\_LEVEL | SYSTEMAIR\_SAVE\_CONTROL\_SUPPLY\_AIR\_FAN\_LEVEL.NORMAL | Fan stage of the supply fan in manual mode | | 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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