# DANFOSS\_VLT\_HVAC\_DRIVE ## `DANFOSS_VLT_HVAC_DRIVE` (FB) `FUNCTION_BLOCK` DANFOSS\_VLT\_HVAC\_DRIVE ### Representation
InOut: | Scope | Name | Type | Initial | Comment | | ----------- | ------------------- | ---------------------------------------------- | -------------------------------------------------- | --------------------------------------------------------------------------------------------------------- | | Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) | | Input | `byUnitId` | `BYTE` | 0 | Device address (1 .. 247) | | Input | `xUpdateActual` | `BOOL` | FALSE |

Update of actual values (on every rising edge
)

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

Update of setpoints (on every rising edge
)

| | Input | `xUpdateConfig` | `BOOL` | FALSE | Update of the configuration (on each rising edge) | | Input | `xEnDevice` | `BOOL` | FALSE | Enable / disable of the frequency converter (FALSE = Off) | | Input | `rSetp` | `REAL` | 0.0 |

Setpoint of the frequency converter (speed, setpoint) (
-100.0 - +100.0%)

| | Input | `xResetShutdown` | `BOOL` | FALSE |

Reset of the device after a shutdown (on every
rising edge)

| | Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device | | Output | `xFb` | `BOOL` | | Operating message (FALSE = Off, TRUE = On) | | Output | `rSetpPercFb` | `REAL` | | Feedback - Current setpoint in percent | | Output | `rOutputFreq` | `REAL` | | Current output frequency in Hz | | Output | `wControlWordFb` | `WORD` | | Feedback - Current control word | | Output | `wStatusWord` | `WORD` | | Current status word | | Output | `dwOperatingHours` | `DWORD` | | Motor operating hours | | Output | `dwElecEnergyTota` | `DWORD` | | Total electrical work in kWh | | Output | `dwCountSwitchOn` | `DWORD` | | Number of switch-ons | | Output | `rElecVoltage` | `REAL` | | Output voltage in volts | | Output | `rElecCurrent` | `REAL` | | Output current in amperes | | Output | `rThermalProtect` | `REAL` | | Thermal motor protection in percent | | Output | `xBit0_Control` | `BOOL` | |

Status of the controller (FALSE = not ready, TRUE = ready
)

| | Output | `xBit1_FreqConv` | `BOOL` | |

Status of the frequency converter (FALSE = not ready, TRUE
= ready)

| | Output | `xBit2_FreeRun` | `BOOL` | |

Status of free run (FALSE = active, TRUE = motor in
operation)

| | Output | `xBit3_AlarmOff` | `BOOL` | |

Status of the fault with shutdown (FALSE = not active,
TRUE = active)

| | Output | `xBit4_Alarm` | `BOOL` | |

Status of the fault without shutdown (FALSE = not active,
TRUE = active)

| | Output | `xBit6_AlarmOffBl` | `BOOL` | |

Status of the fault with shutdown and blocking (FALSE
= not active, TRUE = active)

| | Output | `xBit7_Warn` | `BOOL` | | Status of the warning (FALSE = not active, TRUE = active) | | Output | `xBit8_SetpActual` | `BOOL` | |

Status of speed setpoint/actual value (FALSE = different, TRUE =
equal)

| | Output | `xBit9_LocalBus` | `BOOL` | |

Status of local operation/bus control (FALSE = local
operation, TRUE = bus control)

| | Output | `xBit10_FreqLimit` | `BOOL` | |

Status of the frequency limits (FALSE = frequency is
outside, TRUE = frequency is within)

| | Output | `xBit12_OverTInv` | `BOOL` | |

Status of the inverter overtemperature message (
FALSE = Off, TRUE = On)

| | Output | `xBit13_OverVolt` | `BOOL` | | Status of the overvoltage message (FALSE = Off, TRUE = On) | | Output | `xBit14_OverMomen` | `BOOL` | |

Status of the overtorque message (FALSE = Off, TRUE = On
)

| | Output | `xBit15_OverTherm` | `BOOL` | |

Status of the thermal protective devices (FALSE = no
exceedance, TRUE = limit exceeded)

| | 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 | `dwErrorCode1Dev` | `DWORD` | 0 | Alarm word 1 - Device | | Output | `dwErrorCode2Dev` | `DWORD` | 0 | Alarm word 2 - Device | | Output | `dwWarnCode1Dev` | `DWORD` | 0 | Warning word 1 - Device | | Output | `dwWarnCode2Dev` | `DWORD` | 0 | Warning word 2 - Device | | Output | `dwStateCode1Dev` | `DWORD` | 0 | Extended status word 1 - Device | | Output | `dwStateCode2Dev` | `DWORD` | 0 | Extended status word 2 - Device | | Output | `xBusy` | `BOOL` | | Communication indicator (TRUE = communication) | | Input Const | `wControlMode` | `WORD` | 0 | 0 = speed control, 3 = PID controller | | Input Const | `xCW_Bit15` | `BOOL` | FALSE | FALSE = No reversal, TRUE = Reversal | | Input Const | `xCW_Bit14` | `BOOL` | FALSE |

Most Significant Bit - parameter set selection (00 =
parameter set 1)

| | Input Const | `xCW_Bit13` | `BOOL` | FALSE |

Least Significant Bit - parameter set selection (00 =
parameter set 1)

| | Input Const | `xCW_Bit12` | `BOOL` | FALSE |

FALSE = Relay 02 not activated, TRUE = Relay 02
activated

| | Input Const | `xCW_Bit11` | `BOOL` | FALSE |

FALSE = Relay 01 not activated, TRUE = Relay 01
activated

| | Input Const | `xCW_Bit10` | `BOOL` | TRUE | FALSE = data invalid 1, TRUE = data valid | | Input Const | `xCW_Bit9` | `BOOL` | FALSE | FALSE = Ramp 1, TRUE = Ramp 2 | | Input Const | `xCW_Bit8` | `BOOL` | FALSE | FALSE = No function, TRUE = fixed speed JOG | | Input Const | `xCW_Bit5` | `BOOL` | TRUE | FALSE = hold frequency output, TRUE = use ramp | | Input Const | `xCW_Bit1` | `BOOL` | FALSE |

Most Significant Bit - fixed setpoint selection (00 = setpoint
0)

| | Input Const | `xCW_Bit0` | `BOOL` | FALSE |

Least Significant Bit - fixed setpoint selection (00 = setpoint
0)

| | Input Const | `eDisableMode` | VLT\_HVAC\_DRIVE\_DISABLE\_MODE | VLT\_HVAC\_DRIVE\_DISABLE\_MODE.FREE\_RUN\_STOP | Type of shutdown of the frequency converter | | Input Const | `eCWTimeoutMode` | VLT\_HVAC\_DRIVE\_CONTROL\_WORD\_TIMEOUT\_MODE | VLT\_HVAC\_DRIVE\_CONTROL\_WORD\_TIMEOUT\_MODE.OFF | Function after a control word timeout | | Input Const | `tTimeUpdateCW` | `TIME` | TIME#30s0ms |

Update interval for transmission of the control word (CW =
Control word)

| | Input Const | `tTimeUpdateConfig` | `TIME` | TIME#0ms |

Update interval for the processes influenced by the input
xUpdateConfig influenced

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

Update interval for the processes influenced by the input
xUpdateSetp influenced

| | Input Const | `tTimeUpdateActual` | `TIME` | TIME#3s0ms |

Update interval for the processes influenced by the input
xUpdateActual influenced

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