> 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-library/functionblocks/counter/servicecounter.md).

# ServiceCounter

## `ServiceCounter` (FB)

FUNCTION\_BLOCK ServiceCounter

### Short description

> Signaling of maintenance

### Representation

<figure><img src="https://2592874069-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQR4vCFzt6ixgsqlR3pdR%2Fuploads%2Fgit-blob-fd522374603dc373e13bad1b08fb131339c8c0ee%2Fimage.png?alt=media" alt=""><figcaption></figcaption></figure>

### Interfaces

#### Inputs

#### Outputs

| Name                | Data type | Value range | Initial value | Function                                                |
| ------------------- | --------- | ----------- | ------------- | ------------------------------------------------------- |
| *dLastService*      | DATE      |             |               | Date of the last maintenance                            |
| *dNextService*      | DATE      |             |               | Due date of the next maintenance                        |
| *xAlarm1*           | BOOL      |             |               | Indication that maintenance will be due soon            |
| *xAlarm2*           | BOOL      |             |               | Indication that maintenance is due today                |
| *xAlarm3*           | BOOL      |             |               | Indication that maintenance was already due             |
| *diServiceInDay*    | DINT      |             |               | Display of in how many days the next maintenance is due |
| *diServiceSinceDay* | DINT      |             |               | Days since the last maintenance                         |

#### Setpoints / Parameters

| Name                  | Data type | Value range             | Initial value | Function                                                 |
| --------------------- | --------- | ----------------------- | ------------- | -------------------------------------------------------- |
| **iAlarm1**           | INT       | (0-diServiceInterval)…0 | -10           | Alarm threshold 1 in days (maintenance will be due soon) |
| **iAlarm3**           | INT       | 0…diServiceInterval     | 10            | Alarm threshold 3 in days (maintenance was already due)  |
| **diServiceInterval** | UINT      | 1…1825                  | 365           | Maintenance interval (in days)                           |
| **xReset**            | BOOL      |                         | FALSE         | Reset maintenance day counter                            |
| **xEn**               | BOOL      |                         | TRUE          | Enable outputs xAlarm1 to 3                              |

### Functional description

#### General

This function block provides functionality for signaling maintenance intervals and for resetting the counter after maintenance has been carried out.\
The three outputs for signaling can be temporarily switched off.\
The number of days until the next maintenance (maintenance interval) can be set freely. The number of days since the last maintenance is calculated and displayed.

#### Outputs *xAlarm1*, *xAlarm2* and *xAlarm3*

With the setpoint / parameter **xEn** set to FALSE, the outputs *xAlarm1*, *xAlarm2* and *xAlarm3* are temporarily disabled.\
When the next service interval expires, the setpoint / parameter is reset to the initial value TRUE again.\
\
The output *xAlarm1* is TRUE when the next maintenance date is reached in less than *iAlarm1* days. Since the period is before the maintenance date, the value must be **negative** entered.\
The output *xAlarm2* is TRUE when maintenance is due today (*diServcieInDay* <= 0).\
The output *xAlarm3* is TRUE when the next maintenance date is already at least *iAlarm3* days in the past.\
The three outputs are set to FALSE again when the maintenance day counter is reset with the setpoint / parameter **xReset** . In the process, the variable *dLastService* is assigned the current date.

#### Setpoints / Parameters **iAlarm1**, **iAlarm3** and **diServiceInterval**

The setpoints / parameters are provided with input limits according to the following table:

| Setpoint / parameter                                                | Minimum value         | Maximum value              | Note                           |
| ------------------------------------------------------------------- | --------------------- | -------------------------- | ------------------------------ |
| **diServiceInterval**                                               | 0                     | 5 \* **diServiceInterval** | Service interval               |
| **iAlarm1**                                                         | (0-diServiceInterval) | 0                          | Threshold for output *xAlarm1* |
| **iAlarm2**                                                         | **iAlarm1**           | **iAlarm3**                | Threshold for output *xAlarm2* |
| **iAlarm3**                                                         | **iAlarm2**           | diServiceInterval          | Threshold for output *xAlarm3* |
| The setpoint / parameter **iAlarm2** cannot be changed by the user. |                       |                            |                                |

\
The setpoints / parameters are checked cyclically and, if necessary, limited to the corresponding limit values.\
Any change to a setpoint / parameter can therefore cause a change in another setpoint / parameter.

{% hint style="info" %}
Prerequisite for using the ServiceCounter function block

For correct operation, the use of the TimeRead2 function block is required.
{% endhint %}

### CODESYS

InOut:

| Scope       | Name                | Type   | Initial |
| ----------- | ------------------- | ------ | ------- |
| Input Const | `xEn`               | `BOOL` | TRUE    |
| Input Const | `xReset`            | `BOOL` | FALSE   |
| Input Const | `diServiceInterval` | `UINT` | 365     |
| Input Const | `iAlarm3`           | `INT`  | 10      |
| Input Const | `iAlarm1`           | `INT`  | -10     |
| Output      | `dLastService`      | `DATE` |         |
| Output      | `dNextService`      | `DATE` |         |
| Output      | `xAlarm1`           | `BOOL` |         |
| Output      | `xAlarm2`           | `BOOL` |         |
| Output      | `xAlarm3`           | `BOOL` |         |
| Output      | `diServiceInDay`    | `DINT` |         |
| Output      | `diServiceSinceDay` | `DINT` |         |


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