> 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_epxxxx_fw_3_0_8_mod.md).

# BELIMO\_EPXXXX\_FW\_3\_0\_8\_MOD

## `BELIMO_EPXXXX_FW_3_0_8_MOD` (FB)

`FUNCTION_BLOCK` BELIMO\_EPXXXX\_FW\_3\_0\_8\_MOD

### **Representation**

<figure><img src="https://2592874069-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQR4vCFzt6ixgsqlR3pdR%2Fuploads%2FvYnxDkViIUNhZj36khGM%2FBELIMO_EPXXXX_FW_3_0_8_MOD.png?alt=media&amp;token=c1403c30-9143-4693-9071-3b583f46a00a" alt=""><figcaption></figcaption></figure>

### Guidelines - Software creation

The following function codes (FC) are supported: 3, 4 (in addition: 2, 4, 16)

For write operations on 32-bit data points (2 consecutive Modbus registers), FC16 must be used. No additional registers may then be written in this telegram.

Format of 32-bit data points: Register+0 (LSW): H-byte L-byte Register+1 (MSW): H-byte L-byte

FC 02 may only be used for register 105 (Malfunction and service information, start address = 1664).

* For addressing, the address specifications are to be used, not the register addresses.
* For unused registers, the value 65535 (dec.) is read / written
* Modbus addresses 1 - 247 can be set directly on the valve.

{% hint style="info" %}
All writable register addresses > 100 are persistent and must not be written cyclically
{% endhint %}

InOut:

| Scope       | Name                    | Type                                             | Initial                                                               | Comment                                                                                                                                                                                                          |
| ----------- | ----------------------- | ------------------------------------------------ | --------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Input       | `xEn`                   | `BOOL`                                           | TRUE                                                                  | Enable / disable communication (TRUE = enable)                                                                                                                                                                   |
| Input       | `byUnitId`              | `BYTE`                                           | 1                                                                     | 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       | `xUpdateConfig`         | `BOOL`                                           | FALSE                                                                 | <p>Update of configuration (on every rising<br>edge) (write and read access)</p>                                                                                                                                 |
| Input       | `xUpdateInfo`           | `BOOL`                                           | FALSE                                                                 | <p>Information update (on every rising<br>edge)</p>                                                                                                                                                              |
| Input       | `xResError`             | `BOOL`                                           | FALSE                                                                 | <p>Reinitialization of the outputs <code>eErrorCodeCom</code> or<br><code>stErrorCodeDev</code> to the fault-free state (at each<br>rising edge)</p>                                                             |
| Input       | `rRelSetp`              | `REAL`                                           | 0.0                                                                   | <p>Relative setpoint - position/flow in % (0.0 -<br>100.0 %)</p>                                                                                                                                                 |
| Input       | `eOverrideCon`          | BELIMO\_EPXXXX\_FW\_3\_0\_8\_OVERRIDE\_CONTROL   | BELIMO\_EPXXXX\_FW\_3\_0\_8\_OVERRIDE\_CONTROL.None                   | <p>Position control: 0.0 - 100.0% refer to the relative position<br>Flow control: 0.0 - 100.0% refer to the range 0 - Vmax (address 106)<br>Forced override of the control signal - position/flow (0 = None)</p> |
| Input       | `eCommand`              | BELIMO\_EPXXXX\_FW\_3\_0\_8\_COMMAND             | BELIMO\_EPXXXX\_FW\_3\_0\_8\_COMMAND.None                             | Command for service functions (0 = None)                                                                                                                                                                         |
| Inout       | `ModbusClient`          | `ModbusClientBase`                               |                                                                       | Client of the device                                                                                                                                                                                             |
| Output      | `eSetpSourceFb`         | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SETPOINT\_SOURCE    |                                                                       | <p>Feedback - source for the setpoint -<br>position/flow (1 = Modbus)</p>                                                                                                                                        |
| Output      | `eControlModeFb`        | BELIMO\_EPXXXX\_FW\_3\_0\_8\_CONTROL\_MODE       |                                                                       | Feedback - control mode (1 = flow rate)                                                                                                                                                                          |
| Output      | `rRelSetpFb`            | `REAL`                                           |                                                                       | <p>Feedback - relative setpoint - position/flow in<br>% (0.0 - 100.0 %)</p>                                                                                                                                      |
| Output      | `rRelSetpAnalog`        | `REAL`                                           |                                                                       | <p>Relative setpoint - position/flow in V (0.0 - 10.0<br>V) from input 0 - 10V (address 118 = 0 = analog)</p>                                                                                                    |
| Output      | `rRelPos`               | `REAL`                                           |                                                                       | Relative Position in XXX.X %                                                                                                                                                                                     |
| Output      | `rAbsPos`               | `REAL`                                           |                                                                       | <p>Absolute Position in XXX degrees (rotation) or mm (linear<br>movement)</p>                                                                                                                                    |
| Output      | `rRelVolFlow`           | `REAL`                                           |                                                                       | <p>Relative flow rate in % (0.0 - 100.0 %) (relative to<br><code>Vnom</code> - addresses 112 and 113)</p>                                                                                                        |
| Output      | `rRelVolFlowLimitMaxFb` | `REAL`                                           |                                                                       | <p>Feedback - limit value - maximum percentage<br>flow rate (reference: Vnom) (range: 0.3 - 1.0 Vnom)<br>(Control\_Mode = Flow Control or Position Control)</p>                                                  |
| Output      | `rNomAbsVolFlowUnit`    | `REAL`                                           |                                                                       | <p>Nominal flow rate in the selected unit (addresses<br>112 and 113) (unit setting in address 117)</p>                                                                                                           |
| Output      | `rAbsVolFlowUnit`       | `REAL`                                           |                                                                       | <p>Absolute flow rate in the selected unit (unit setting<br>in address 117)</p>                                                                                                                                  |
| Output      | `eVolFlowUnitFb`        | BELIMO\_EPXXXX\_FW\_3\_0\_8\_VOLUME\_FLOW\_UNIT  |                                                                       | <p>Feedback - unit for the absolute flow rate (<br>unit setting in address 117)</p>                                                                                                                              |
| Output      | `eSensor1TypeFb`        | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SENSOR\_1\_TYPE     |                                                                       | Feedback - sensor type (address 107: sensor type)                                                                                                                                                                |
| Output      | `rSensor1ValueUnit`     | `REAL`                                           |                                                                       | <p>Current value of sensor 1 in the selected unit (<br>address 107: sensor type)</p>                                                                                                                             |
| Output      | `eOverrideConFb`        | BELIMO\_EPXXXX\_FW\_3\_0\_8\_OVERRIDE\_CONTROL   |                                                                       | <p>Current state - forced override of the control signal -<br>position/flow (0 = None)</p>                                                                                                                       |
| Output      | `eCommandFb`            | BELIMO\_EPXXXX\_FW\_3\_0\_8\_COMMAND             |                                                                       | <p>Current state - command for service functions (0 = None<br>)</p>                                                                                                                                              |
| Output      | `eDeviceType`           | BELIMO\_EPXXXX\_FW\_3\_0\_8\_DEVICE\_TYPE        |                                                                       | <p>Current state - device type (0 = Device not<br>connected)</p>                                                                                                                                                 |
| Output      | `eBusTermin`            | BELIMO\_EPXXXX\_FW\_3\_0\_8\_BUS\_TERMINATION    |                                                                       | Status of the Modbus terminating resistor (Active = Enabled)                                                                                                                                                     |
| Output      | `sSerialNum`            | `STRING`                                         |                                                                       | Device serial number                                                                                                                                                                                             |
| Output      | `wFirmwareVer`          | `WORD`                                           |                                                                       | Firmware version of the device                                                                                                                                                                                   |
| Output      | `eAO`                   | eManNum                                          | eManNum.Auto                                                          | <p>Display - manual override on the device (actuator disconnected)<br>(0 = automatic)</p>                                                                                                                        |
| 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      | `stErrorCodeDev`        | `STRING`                                         |                                                                       | String with the numbers of the active device errors                                                                                                                                                              |
| Output      | `xBusy`                 | `BOOL`                                           |                                                                       | Communication indicator (TRUE = communication)                                                                                                                                                                   |
| Input Const | `tBusFailTimeout`       | `TIME`                                           | TIME#2m0s0ms                                                          | <p>Time period for evaluating a communication error (0 =<br>disabled, 1 - 3600s)</p>                                                                                                                             |
| Input Const | `eBusFailPosition`      | BELIMO\_EPXXXX\_FW\_3\_0\_8\_BUS\_FAIL\_POSITION | BELIMO\_EPXXXX\_FW\_3\_0\_8\_BUS\_FAIL\_POSITION.None\_Last\_setpoint | <p>Definition of the action in case of a timeout of the<br>communication monitoring</p>                                                                                                                          |
| Input Const | `eSensor_1_Type`        | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SENSOR\_1\_TYPE     | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SENSOR\_1\_TYPE.None                     | Definition of the type of sensor 1 (0 = None)                                                                                                                                                                    |
| Input Const | `rRelVolFlowLimitMax`   | `REAL`                                           | 100.0                                                                 | <p>Limit value - maximum percentage flow rate (reference:<br>Vnom) (range: 0.3 - 1.0 Vnom) (Control\_Mode = Flow<br>Control or Position Control)</p>                                                             |
| Input Const | `eSetpSource`           | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SETPOINT\_SOURCE    | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SETPOINT\_SOURCE.Bus                     | <p>Source for the setpoint - position/volumetric flow (1 = Modbus<br>)</p>                                                                                                                                       |
| Input Const | `eVolFlowUnit`          | BELIMO\_EPXXXX\_FW\_3\_0\_8\_VOLUME\_FLOW\_UNIT  | BELIMO\_EPXXXX\_FW\_3\_0\_8\_VOLUME\_FLOW\_UNIT.m3\_per\_hour         | <p>Unit for the absolute flow rate (unit setting in the<br>address 117)</p>                                                                                                                                      |
| Input Const | `eControlMode`          | BELIMO\_EPXXXX\_FW\_3\_0\_8\_CONTROL\_MODE       | BELIMO\_EPXXXX\_FW\_3\_0\_8\_CONTROL\_MODE.Flow\_Control              | Control mode (1 = volumetric flow)                                                                                                                                                                               |
| Input Const | `tTimeUpdateInfo`       | `TIME`                                           | TIME#0ms                                                              | <p>Update interval for the operations that are influenced by the input<br><code>xUpdateInfo</code> influenced</p>                                                                                                |
| Input Const | `tTimeUpdateConfig`     | `TIME`                                           | TIME#0ms                                                              | <p>Update interval for the operations that are influenced by the input<br><code>xUpdateConfig</code> influenced</p>                                                                                              |
| Input Const | `tTimeUpdateSetp`       | `TIME`                                           | TIME#45s0ms                                                           | <p>Update interval for the operations that are influenced by the input<br><code>xUpdateSetp</code> influenced</p>                                                                                                |
| Input Const | `tTimeUpdateActual`     | `TIME`                                           | TIME#3s0ms                                                            | <p>Update interval for the operations that are influenced by the input<br><code>xUpdateActual</code> influenced</p>                                                                                              |


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