> 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/abb/abb_b21_23_24.md). # ABB\_B21\_23\_24 ## `ABB_B21_23_24` (FB) `FUNCTION_BLOCK` ABB\_B21\_23\_24 ### **Representation**
InOut: | Scope | Name | Type | Initial | Comment | | ----------- | -------------------- | ------------------ | ------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | | Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) | | Input | `byUnitId` | `BYTE` | 0 | Address of the device | | Input | `xUpdateActual` | `BOOL` | FALSE |

Update of actual values (on every rising edge
)

| | Input | `xUpdateCounter` | `BOOL` | FALSE |

Update of the meter readings (on every rising
edge)

| | Input | `xUpdateInfo` | `BOOL` | FALSE |

Update of the serial number / device type (on every
rising edge)

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

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

| | Input | `xSendSysCommand` | `BOOL` | FALSE |

Activation of the transmission of system commands (on every
rising edge) (Prerequisite: valid address and
valid value)

| | Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device | | Output | `rU1N` | `REAL` | | Phase voltage L1 - N in V | | Output | `rU2N` | `REAL` | | Phase voltage L2 - N in V | | Output | `rU3N` | `REAL` | | Phase voltage L3 - N in V | | Output | `rU12` | `REAL` | | Line voltage L1 - L2 in V | | Output | `rU23` | `REAL` | | Line voltage L2 - L3 in V | | Output | `rU31` | `REAL` | | Line voltage L3 - L1 in V | | Output | `rIL1` | `REAL` | | Line current L1 in A | | Output | `rIL2` | `REAL` | | Line current L2 in A | | Output | `rIL3` | `REAL` | | Line current L3 in A | | Output | `rILN` | `REAL` | | Current in the neutral conductor in A | | Output | `rPhaseAnglePowTo` | `REAL` | | Phase angle - power - total in degrees | | Output | `rPowerFactorTo` | `REAL` | | Power factor - total | | Output | `rPowerFactorL1` | `REAL` | | Power factor L1 | | Output | `rPowerFactorL2` | `REAL` | | Power factor L2 | | Output | `rPowerFactorL3` | `REAL` | | Power factor L3 | | Output | `rActivePowerTo` | `REAL` | | Active power - total in W | | Output | `rActivePowerL1` | `REAL` | | Active power L1 in W | | Output | `rActivePowerL2` | `REAL` | | Active power L2 in W | | Output | `rActivePowerL3` | `REAL` | | Active power L3 in W | | Output | `rApparentPowerTo` | `REAL` | | Apparent power - total in VA | | Output | `rApparentPowerL1` | `REAL` | | Apparent power L1 in VA | | Output | `rApparentPowerL2` | `REAL` | | Apparent power L2 in VA | | Output | `rApparentPowerL3` | `REAL` | | Apparent power L3 in VA | | Output | `rReactivePowerTo` | `REAL` | | Reactive power - total in var | | Output | `rReactivePowerL1` | `REAL` | | Reactive power L1 in var | | Output | `rReactivePowerL2` | `REAL` | | Reactive power L2 in var | | Output | `rReactivePowerL3` | `REAL` | | Reactive power L3 in var | | Output | `rFrequency` | `REAL` | | Frequency in Hz | | Output | `rActiveTariff` | `REAL` | | Active tariff | | Output | `uliActEneImp` | `ULINT` | | Imported active energy - total in kWh | | Output | `uliActEneImpTotal1` | `ULINT` | | Consumed active energy - Total - Tariff 1 in kWh | | Output | `uliActEneImpTotal2` | `ULINT` | | Consumed active energy - Total - Tariff 2 in kWh | | Output | `uliActEneImpTotal3` | `ULINT` | | Imported active energy - total - tariff 3 in kWh | | Output | `uliActEneImpTotal4` | `ULINT` | | Imported active energy - total - tariff 4 in kWh | | Output | `uliActEneExp` | `ULINT` | | Exported active energy - total in kWh | | Output | `uliActEneExpTotal1` | `ULINT` | | Delivered active energy - Total - Tariff 1 in kWh | | Output | `uliActEneExpTotal2` | `ULINT` | | Delivered active energy - Total - Tariff 2 in kWh | | Output | `uliActEneExpTotal3` | `ULINT` | | Exported active energy - total - tariff 3 in kWh | | Output | `uliActEneExpTotal4` | `ULINT` | | Exported active energy - total - tariff 4 in kWh | | Output | `uliReaEneImp` | `ULINT` | | Imported reactive energy - total in kVarh | | Output | `uliReaEneImpTotal1` | `ULINT` | | Consumed reactive energy - Total - Tariff 1 in kVarh | | Output | `uliReaEneImpTotal2` | `ULINT` | | Consumed reactive energy - Total - Tariff 2 in kVarh | | Output | `uliReaEneImpTotal3` | `ULINT` | | Imported reactive energy - total - tariff 3 in kVarh | | Output | `uliReaEneImpTotal4` | `ULINT` | | Imported reactive energy - total - tariff 4 in kVarh | | Output | `uliReaEneExp` | `ULINT` | | Exported reactive energy - total in kVarh | | Output | `uliReaEneExpTotal1` | `ULINT` | | Delivered reactive energy - Total - Tariff 1 in kVarh | | Output | `uliReaEneExpTotal2` | `ULINT` | | Delivered reactive energy - Total - Tariff 2 in kVarh | | Output | `uliReaEneExpTotal3` | `ULINT` | | Exported reactive energy - total - tariff 3 in kVarh | | Output | `uliReaEneExpTotal4` | `ULINT` | | Exported reactive energy - total - tariff 4 in kVarh | | Output | `uliAppEneImp` | `ULINT` | | Imported apparent energy - total in kVAh | | Output | `uliAppEneExp` | `ULINT` | | Exported apparent energy - total in kVAh | | Output | `sDeviceType` | `STRING` | | Device type and functionality | | Output | `dwSerialNum` | `DWORD` | | Meter serial number (32 bit) | | 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 | `sErrorCodeDev_1` | `STRING` | |

String 1 with the numbers of active device errors (Register
16#8A13)

| | Output | `sErrorCodeDev_2` | `STRING` | |

String 2 with the numbers of active device errors (Register
16#8A14)

| | Output | `sErrorCodeDev_3` | `STRING` | |

String 3 with the numbers of active device errors (Register
16#8A15)

| | Output | `sErrorCodeDev_4` | `STRING` | |

String 4 with the numbers of active device errors (Register
16#8A16)

| | Output | `xBusy` | `BOOL` | | Communication indicator (TRUE = communication) | | Input Const | `wSysRegVal` | `WORD` | 0 | Value of the register for the system command | | Input Const | `wSysRegAdr` | `WORD` | 16#8F00 | Address of the register for the system command | | Input Const | `xEnAlarmDevice` | `BOOL` | FALSE |

Enable / block outputs xAlarmDevice or
stErrorCodeDev\_X (FALSE = blocking of the evaluation of the
alarm states)

| | Input Const | `tTimeUpdateInfo` | `TIME` | TIME#60m0s0ms |

Update interval for the operations that are influenced by the input
xUpdateInfo influenced

| | Input Const | `tTimeUpdateCounter` | `TIME` | TIME#5m0s0ms |

Update interval for the operations that are influenced by the input
xUpdateCounter influenced

| | Input Const | `tTimeUpdateActual` | `TIME` | TIME#1m0s0ms |

Update interval for the operations that are influenced by the input
xUpdateActual influenced

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