> 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/belimo/belimo_cq24a_bac_mod.md).

# BELIMO\_CQ24A\_BAC\_MOD

## `BELIMO_CQ24A_BAC_MOD` (FB)

`FUNCTION_BLOCK` BELIMO\_CQ24A\_BAC\_MOD

### **Representation**

<figure><img src="/files/fd8bf007b25305fa856e1988fefa1499bd3a9a4e" 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 (1 .. 247)                                                                                                                         |
| Input       | `xUpdateActual`     | `BOOL`                                | FALSE                                                    | <p>Update of actual values (on every rising edge<br>)</p>                                                                                         |
| Input       | `xUpdateSetp`       | `BOOL`                                | FALSE                                                    | <p>Update of setpoints (on every rising edge<br>)</p>                                                                                             |
| Input       | `xResError`         | `BOOL`                                | FALSE                                                    | <p>Reinitialization of the outputs <code>eErrorCodeCom</code> or<br><code>sErrorCodeDev</code> to the fault-free state (on every rising edge)</p> |
| Input       | `rSetp`             | `REAL`                                | 0.0                                                      | Setpoint - position in % (0.0 - 100.0 %)                                                                                                          |
| Inout       | `ModbusClient`      | `ModbusClientBase`                    |                                                          | Client of the device                                                                                                                              |
| Output      | `rRelPos`           | `REAL`                                |                                                          | Relative position in XXX.X %                                                                                                                      |
| Output      | `rAbsPos`           | `REAL`                                |                                                          | Absolute position in XXX.X degrees (rotation)                                                                                                     |
| Output      | `eOverrideConFb`    | BELIMO\_OverrideControl               |                                                          | <p>Current state - forced override of the actuating signal -<br>position (0 = None)</p>                                                           |
| Output      | `sSerialNum`        | `STRING`                              |                                                          | Serial number of the device                                                                                                                       |
| 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`     | `STRING`                              |                                                          | String with the numbers of the active device errors                                                                                               |
| Output      | `xBusy`             | `BOOL`                                |                                                          | Communication indicator (TRUE = communication)                                                                                                    |
| Input Const | `eRelPosMode`       | BELIMO\_CQ24A\_BAC\_MOD\_RELPOS\_MODE | BELIMO\_CQ24A\_BAC\_MOD\_RELPOS\_MODE.RELATIVE\_TO\_RMAX |                                                                                                                                                   |
| Input Const | `eCommand`          | BELIMO\_Command                       | BELIMO\_Command.None                                     | Triggering of test functions (0 = None)                                                                                                           |
| Input Const | `wTimeBusFail`      | `WORD`                                | 0                                                        | <p>Duration of the bus watchdog timeout (60 - 3600s, 0 =<br>disabling)</p>                                                                        |
| Input Const | `rBusFailPos`       | `REAL`                                | 0.0                                                      | <p>Position in the event of a bus watchdog timeout in % (0.0 -<br>100.0 %)</p>                                                                    |
| Input Const | `rMax`              | `REAL`                                | 100.0                                                    | <p>Absolute maximum value - actuating signal - position in % (0.0 -<br>100.0 %)</p>                                                               |
| Input Const | `eOverrideCon`      | BELIMO\_OverrideControl               | BELIMO\_OverrideControl.None                             | Forced override of the actuating signal - position (0 = None)                                                                                     |
| Input Const | `tTimeUpdateSetp`   | `TIME`                                | TIME#45s0ms                                              | <p>Update interval for the processes influenced by the input<br><code>xUpdateSetp</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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