| Volume pwrb | |
| Attributes: Runtime | Development | System | Template | Detail C Binding: Struct | Class | Code ClassTree | INDEX NO INDEX |
|
Class Filter
|
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|---|---|---|
| Version | 1.0 | |
| Modified | 26-MAY-2023 14:29:26.00 | |
| Code | rt_plc_arithm.c | |
First Order Lag Filter.
The input signal gets an exponential smoothing.
VAL = a * In + (1 - a) * X = X + a * (In - X) , where
X = FeedB, if FeedB is connected,
ActVal[t-1] otherwise
a = 1 - 1 / (1 + ScanTime / FiltCon)
An external signal may also be used as feedback; e.g.
Example
If a (= ScanTime / FiltCon) is small, 0.1 - 0.2, the output gets a character of a slowly moving average.
| RtBody attributes pwr_sClass_filter | |||
|---|---|---|---|
| Float32 | In | IN | Value of the input signal. |
| Float32 | FeedB | FB | External feedback. If the input is left open the VAL-output will be used as an internal input signal. |
| Float32 | ActVal | VAL | Output signal, see above. |
| Pointer to Float32 | ScanTime | ScanTime | The program cycle period (= sampling interval), in seconds, is stored automatically at the compilation. |
| Float32 | FiltCon | FiltCon | The filter constant, in seconds, can be fixed or adjustable. FiltCon > ScanTime is a valid value. FiltCon = ScanTime makes no filtering. |
| Int32 | AccCon | AccCon | The operator's authorities to change FiltCont. 0 -- Changes not allowed. != 0 -- Changes allowed. |
| Float32 | MinCon | MinCon | The minimum and maximum allowed value of FiltCon at changes made by an operator. |
| Float32 | MaxCon | MaxCon | |
| DevBody attributes | |||
|---|---|---|---|
| PlcNode | PlcNode | ||
| GraphPlcNode | |
|---|---|
| object_type | 127 |
| parameters[0] | 2 |
| parameters[1] | 0 |
| parameters[2] | 1 |
| parameters[3] | 0 |
| subwindows | 0 |
| graphmethod | 0 (standard, individual attributes) |
| graphindex | 0 |
| default_mask[0] | 1 |
| default_mask[1] | 1 |
| segname_annotation | 1 |
| compmethod | 32 |
| compindex | 0 |
| tracemethod | 0 |
| traceindex | 0 |
| executeordermethod | 2 |
| objname | Filter |
| graphname | Filter |
| debugpar | |
| In Input | ||
|---|---|---|
| Class | Input | |
| Type | Float32 | |
| Flags | REDUTRANSFER | |
| GraphName | IN | |
| Body | RtBody | |
Value of the input signal.
| FeedB Input | ||
|---|---|---|
| Class | Input | |
| Type | Float32 | |
| Flags | STATE | NOEDIT | REDUTRANSFER | |
| GraphName | FB | |
| Body | RtBody | |
External feedback. If the input is left open the VAL-output will be used as an internal input signal.
| ActVal Output | ||
|---|---|---|
| Class | Output | |
| Type | Float32 | |
| Flags | STATE | NOEDIT | REDUTRANSFER | |
| GraphName | VAL | |
| Body | RtBody | |
Output signal, see above.
| ScanTime Intern | ||
|---|---|---|
| Class | Intern | |
| Type | Pointer to Float32 | |
| Flags | INVISIBLE | POINTER | PRIVATE | |
| GraphName | ScanTime | |
| Body | RtBody | |
The program cycle period (= sampling interval), in seconds, is stored automatically at the compilation.
| FiltCon Intern | ||
|---|---|---|
| Class | Intern | |
| Type | Float32 | |
| Flags | REDUTRANSFER | |
| GraphName | FiltCon | |
| Body | RtBody | |
The filter constant, in seconds, can be fixed or adjustable. FiltCon > ScanTime is a valid value. FiltCon = ScanTime makes no filtering.
| AccCon Intern | ||
|---|---|---|
| Class | Intern | |
| Type | Int32 | |
| Flags | ||
| GraphName | AccCon | |
| Body | RtBody | |
The operator's authorities to change FiltCont. 0 -- Changes not allowed. != 0 -- Changes allowed.
| MinCon Intern | ||
|---|---|---|
| Class | Intern | |
| Type | Float32 | |
| Flags | ||
| GraphName | MinCon | |
| Body | RtBody | |
The minimum and maximum allowed value of FiltCon at changes made by an operator.
| MaxCon Intern | ||
|---|---|---|
| Class | Intern | |
| Type | Float32 | |
| Flags | ||
| GraphName | MaxCon | |
| Body | RtBody | |
| PlcNode Buffer | ||
|---|---|---|
| Class | Buffer | |
| Type | PlcNode | |
| Flags | INVISIBLE | |
| Body | DevBody | |