SWI_2P: On/off switch with adjustable switch-on and switch-off point
The SWI_2P (FB411) block generates a binary output signal after a comparison between the input signal and the switch-on and switch-off point.
Functionality
The block generates the binary output signal [Out] after a comparison between the input signal [In] and the switch-on point [SwiOnPt] and the switch-off point [SwiOffPt].
The relative mutual position of the switch-on point [SwiOnPt] and the switch-off point [SwiOffPt] defines the direction of control action.
The block function can be fully enabled or disabled via pin [EnFnct].
Action: direct
Action: reverse
Inputs
Pin | E | Description |
EnFnct | p | Enable function. 1 (Yes) = The function is enabled. 0 (No) = The function is disabled. |
In | pa | Input. |
SwiOnPt | pa | Switch-on point. The switch-on and switch-off points define the switching frequency and the direction of control action. The direction of control action is direct if [SwiOnPt] ≥ [SwiOffPt]. The direction of control action is reverse if [SwiOnPt] < [SwiOffPt]. |
SwiOffPt | pa | Switch-off point. The switch-on and switch-off points define the switching frequency and the direction of control action (see [SwiOnPt]). |
Outputs
Pin | E | Description |
Out | a | Output. |
Input values
Pin | Description | Data type | Default value | E.g. Engineering unit or Text group | Min. | Max. |
EnFnct | Enable function. | Boolean | 1 (Yes) | No, Yes |
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In | Input. | Real | 0.0 |
| -3.403E38 | 3.403E38 |
SwiOnPt | Switch-on point. | Real | 0.0 |
| -3.403E38 | 3.403E38 |
SwiOffPt | Switch-off point. | Real | 0.0 |
| -3.403E38 | 3.403E38 |
Output values
Pin | Description | Data type | Default value | E.g. Engineering unit or Text group | Min. | Max. |
Out | Output. | Boolean | 0 (Off) | Off, On |
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Application
- In air conditioning and heating to control (disable and enable) components and aggregates.
- General: Performance of switching functions with known and settable switch-on and switch-off point.
If a setpoint with settable position relative to the switch-on and switch-off point for On/Off switches/On/Off controllers represents a known or adjustable variable, block SWI_2PH (FB432) is to be used.
Process response
The block is processed with the values at the inputs, starting from the first cycle in the process. During start-up, if the value [In] is between the switch-on and switch-off point, the output is set to [Out] = 0 (Off).
Troubleshooting
Standard (see General rules and information).