Advanced Operations
6.3.3.9 Function set to FREQ. Control/PID CONTROL mode
FREQ. Control /PID CONTROL
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| Default value: LINEAR |
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| There are two SET FUNCTION menus. |
| SET FUNCTION | First menu: Selects the basic function of the relay. | |
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| Second menu: Defines whether the output frequency signal is depending linear to the process |
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| value or the output frequency signal is working as a PID controller. |
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| LINEAR | Signal is linearly dependent on the process value. |
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| PID CONTROL | Signal works as a PID controller. |
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| Default value: 0 seconds |
| SET TRANSFER | Sets a substitute output frequency when some error conditions are detected in the selected | |
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| source or if the source is missing. |
| SET MODE | Default value: AUTOMATIC | |
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| AUTOMATIC | The relay output works as a PID controller |
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| MANUAL | The relay output frequency has a cycle duration which is set in the MANUAL OUTPUT menu. |
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| MANUAL OUTPUT | Indicates the current cycle duration of the output frequency. | |
| Additionally the cycle duration can be set (condition: SET MODE=MANUAL). | ||
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| PHASE | Default value: DIRECT | |
| With this menu the leading sign of the control deviation for the PID controller can be reversed. | ||
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| SET POINT | Default value: 10 | |
| Sets the process value which is controlled by the PID controller. | ||
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| Default value: 1 |
| DEAD ZONE | The dead zone is a band around the set point. In this band the PID controller does not change | |
| the output frequency. This band is determined as set point +/- dead zone. The dead zone | ||
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| stabilizes the PID controlled system which have a tendency to oscillate. |
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| HIGH ALARM | Default value: 1 second | |
| Sets the maximum cycle duration which can be set by the PID controller. | ||
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| LOW ALARM | Default value: 10 seconds | |
| Sets the minimum cycle duration which can be set by the PID controller. | ||
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| Default value: 1 |
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| Sets the proportional part of the PID controller. |
| PROPORTIONAL | The proportional part of the controller generates an output signal which is linearly dependent to | |
| the control deviation. The proportional part reacts on any changes at the input but starts to | ||
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| oscillate easily if the value is set to high. The proportional part cannot completely compensate |
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| disturbances. |
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| Default value: 15 minutes |
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| Sets the integration part of the PID controller. |
| INTEGRAL | The integration part of the controller generates an output signal. The output signal increases | |
| linearly if the control deviation is constant. The integration part responds slower than the | ||
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| proportional part and can completely compensate disturbances. The higher the integration part, |
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| the slower it responds. If the integration part is set to low, it starts to oscillate. |
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| Default value: 5 minutes |
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| Sets the derivative part of the PID controller. |
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| The derivative part of the PID controller generates an output signal which depends on the control |
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| deviation changes. The faster the control deviation changes, the higher the output signal gets. |
| DERIVATIVE | The derivative part creates an output signal as long as the control deviation changes. If the | |
| control deviation is constant, no signal is created. | ||
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| The derivative part is able to smoothen the oscillation caused by the proportional part. The |
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| derivative part allows the proportional part to be set higher and the controller responds faster. |
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| If there is no knowledge about the controlled process behavior, it is recommended to set this part |
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| to “0”, because this part tends to oscillate strongly. |
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