> 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/bd_sensors/bd_sensors_dct_531.md).

# BD\_SENSORS\_DCT\_531

## `BD_SENSORS_DCT_531` (FB)

`FUNCTION_BLOCK` BD\_SENSORS\_DCT\_531

### **Representation**

<figure><img src="/files/a1f3380e7b7a8a5cad3a402c83a70ecbd2a81af8" alt=""><figcaption></figcaption></figure>

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      | <p>Update of actual values (on every rising edge<br>)</p>                                                                                                           |
| Input       | `xUpdateInfo`           | `BOOL`             | FALSE      | Device information update (on every rising edge)                                                                                                                    |
| Inout       | `ModbusClient`          | `ModbusClientBase` |            | Client of the device                                                                                                                                                |
| Output      | `rPressureUnit`         | `REAL`             |            | Current actual pressure value in the unit of measurement                                                                                                            |
| Output      | `rPressureMinUnit`      | `REAL`             |            | <p>Minimum value - actual pressure value in the unit of measurement (<br>measured value memory)</p>                                                                 |
| Output      | `rPressureMaxUnit`      | `REAL`             |            | <p>Maximum value - actual pressure value in the unit of measurement (<br>measured value memory)</p>                                                                 |
| Output      | `rPressureRangeMinUnit` | `REAL`             |            | Minimum value - measuring range in the unit of measurement                                                                                                          |
| Output      | `rPressureRangeMaxUnit` | `REAL`             |            | Maximum value - measuring range in the unit of measurement                                                                                                          |
| Output      | `sUnit`                 | `STRING`           |            | Unit of measurement                                                                                                                                                 |
| Output      | `xSensorOffsetInDevice` | `BOOL`             |            | <p>Indication of whether the sensors must be calibrated in the device<br>(TRUE = calibration in the device required, FALSE = calibration in the<br>FB required)</p> |
| Output      | `dwSerialNum`           | `DWORD`            |            | Device serial number                                                                                                                                                |
| 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 | `rPressureOffset`       | `REAL`             | 0.0        | <p>Constant measured value offset for the transmitted pressure -<br>actual value</p>                                                                                |
| Input Const | `diAdrOffset`           | `DINT`             | 0          | <p>Offset for calculating the Modbus addresses (from the Modbus<br>registers) (permitted range: -1, 0, +1)</p>                                                      |
| Input Const | `tTimeUpdateInfo`       | `TIME`             | TIME#0ms   | <p>Update interval for the processes influenced by the input<br><code>xUpdateInfo</code> influenced</p>                                                             |
| Input Const | `tTimeUpdateActual`     | `TIME`             | TIME#3s0ms | <p>Update interval for the processes influenced by the input<br><code>xUpdateActual</code> influenced</p>                                                           |


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