# AbsB

## `AbsB` (FB)

FUNCTION\_BLOCK AbsB

### Short description

> Anti-blocking protection for a binary signal

### Representation

<figure><img src="/files/17da8b8f3a666ae976f08fc72f137f74fa6285ab" alt=""><figcaption></figcaption></figure>

### Interfaces

#### Inputs

| Name  | Data type | Value range | Initial value | Function          |
| ----- | --------- | ----------- | ------------- | ----------------- |
| *xFb* | BOOL      |             |               | Operating message |

#### Outputs

| Name          | Data type       | Value range | Initial value | Function                                          |
| ------------- | --------------- | ----------- | ------------- | ------------------------------------------------- |
| *xOut*        | BOOL            |             |               | Enable - Output                                   |
| *xAbsOn*      | BOOL            |             |               | Indicator - anti-blocking process                 |
| *dtAbsLastOn* | DATE\_AND\_TIME |             |               | Start date/time of the last anti-blocking process |

#### Setpoints / parameters

| Name             | Data type | Value range | Initial value | Function                                |
| ---------------- | --------- | ----------- | ------------- | --------------------------------------- |
| **tMinFbTime**   | TIME      |             | T#30s         | Minimum run time                        |
| **tTime**        | TIME      |             | 120s          | Duration of the anti-blocking process   |
| **eDay**         | eDoW      |             | eDow\.Monday  | Weekday of the anti-blocking process    |
| **todStartTime** | TOD       |             | 08:00:00      | Start time of the anti-blocking process |

### Function description

#### General

This function block is used to monitor the operating message *xFb* for activity. The inspection period covers 168 hours each time (= 1 week).\
The operating message *xFb* is active if it is continuously active once during the inspection period for the minimum operating duration **tMinFbTime** The blocking protection process is thereby prevented, the inspection period starts again.\
If no operating message is available, the request / release can alternatively be connected.\
\
If no activity is recorded during the inspection period, the blocking protection process (release - output *xOut* = TRUE) is triggered after the time duration **tTime** on the weekday **eDay** at the time **todStartTime** .\
At the same time, the inspection period starts again.\
The initial triggering of the blocking protection process can, depending on the relevant settings (weekday **eDay** and **todStartTime**).

> **Example**
>
> inspection period ends on Tuesday morning, triggering of the blocking protection process only on the following Monday.\
> At the output *dtAbsLastOn* the start date and start time of the last anti-blocking process are available.
>
> \
> Prerequisite for the use of the AbsB function block
>
> The use of the TimeRead2 function block is required for correct operation.

#### Enable - Output *xOut*

| *xFb* | Anti-blocking process | *xOut* | Notes                            |
| ----- | --------------------- | ------ | -------------------------------- |
| X     | FALSE                 | FALSE  | Anti-blocking process not active |
| X     | TRUE                  | TRUE   | Anti-blocking process active     |

Legend: X = any

#### Indicator - anti-blocking process *xAbsOn*

| *xFb* | Anti-blocking process | *xAbsOn* | Notes                            |
| ----- | --------------------- | -------- | -------------------------------- |
| X     | FALSE                 | FALSE    | Anti-blocking process not active |
| X     | TRUE                  | TRUE     | Anti-blocking process active     |

Legend: X = any

#### Setpoint / parameters **eDay**

The anti-blocking function can be globally disabled by setting **eDay** = eDow\.Inactive.

#### Setpoint / parameters **tTime**

The anti-blocking function can be globally disabled by setting **tTime** = 0s can be globally disabled.

### CODESYS

InOut:

| Scope       | Name           | Type   | Initial           |
| ----------- | -------------- | ------ | ----------------- |
| Input       | `xFb`          | `BOOL` |                   |
| Input Const | `tMinFbTime`   | `TIME` | TIME#30s0ms       |
| Input Const | `tTime`        | `TIME` | TIME#2m0s0ms      |
| Input Const | `eDay`         | eDoW   | eDow\.Monday      |
| Input Const | `todStartTime` | `TOD`  | TIME\_OF\_DAY#8:0 |
| Output      | `xOut`         | `BOOL` |                   |
| Output      | `xAbsOn`       | `BOOL` |                   |
| Output      | `dtAbsLastOn`  | `DT`   |                   |


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