> 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/damping/ramp.md).

# Ramp

## `Ramp` (FB)

FUNCTION\_BLOCK Ramp

### Short description

> Limitation of the signal change of an analog input signal\
> Typical application: attenuation / filtering

### Representation

<figure><img src="https://2592874069-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQR4vCFzt6ixgsqlR3pdR%2Fuploads%2Fgit-blob-fec3863ea7b47a6a0d292edcf16a4965ca7ce958%2Fimage.png?alt=media" alt=""><figcaption></figcaption></figure>

### Interfaces

#### Inputs

| Name  | Data type | Value range | Initial value | Function     |
| ----- | --------- | ----------- | ------------- | ------------ |
| *rIn* | REAL      |             |               | Analog input |

#### Outputs

| Name          | Data type | Value range | Initial value | Function            |
| ------------- | --------- | ----------- | ------------- | ------------------- |
| *rOut*        | REAL      |             |               | Analog value output |
| *xRampActive* | BOOL      |             |               | Status - ramp       |

#### Setpoints / Parameters

| Name           | Data type | Value range | Initial value    | Function                       |
| -------------- | --------- | ----------- | ---------------- | ------------------------------ |
| **rVariation** | REAL      | 0 …         | 100              | Maximum change per unit time   |
| **tTime**      | TIME      |             | T#10s            | Time unit                      |
| **rInitValue** | REAL      |             | 0                | Initial value                  |
| **eInitial**   | eInit     |             | eInit.InputValue | Selection of the initial value |
| **tInitDelay** | TIME      |             | T#5s             | Start delay                    |

### Functional description

#### General

The analog input signal *rIn* is continuously checked for changes in value.\
If the signal at the analog value output *rOut* deviates from the input signal, it follows the input signal with the maximum signal change rate.

> **Setting the time unit tTime**
>
> This setpoint / parameter may only take values >= 0.\
> The maximum signal change rate is determined by the quotient of the setpoints / parameters **rVariation** and **tTime** formed (**tTime** > 0s).

The maximum signal change rate is determined by the quotient of the setpoints / parameters **rVariation** and task cycle time formed (**tTime** = 0s).\
The maximum signal change rate is effective for both positive and negative value changes at the input *rIn* effective.

#### Type of initialization **eInitial**

With this setpoint / parameter, the type of initialization of the analog value input *rIn* is defined.\
Initialization is performed once after each CPU restart.\
\
The following options are possible:

| Type                    | Value of initialization | Note                     |
| ----------------------- | ----------------------- | ------------------------ |
| eInit.InitValue         | **rInitValue**          | Adjustable initial value |
| eInit.InputValue        | *rIn*                   | eInit2.InputValue        |
| eInit.InputValueDelayed | *rIn*                   | Delayed input value      |

Initialization is performed continuously regardless if the setpoint / parameter **tTime** has the value T#0s.

### CODESYS

InOut:

| Scope       | Name          | Type   | Initial          |
| ----------- | ------------- | ------ | ---------------- |
| Input       | `rIn`         | `REAL` |                  |
| Input Const | `rVariation`  | `REAL` | 100              |
| Input Const | `tTime`       | `TIME` | TIME#10s0ms      |
| Input Const | `rInitValue`  | `REAL` | 0                |
| Input Const | `eInitial`    | eInit  | eInit.InputValue |
| Input Const | `tInitDelay`  | `TIME` | TIME#5s0ms       |
| Output      | `rOut`        | `REAL` |                  |
| Output      | `xRampActive` | `BOOL` |                  |


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