1: Priority
This setting determines whether it is min. or max. output that is prioritised. This setting is used for the dynamic input selection
feature. “Maximum output” results in selection of the input that gives the greatest output. “Minimum output” results in selection of the
input that gives the smallest output.
2: Output type
Choose between relay or analogue output. The following parameters marked “analogue” only apply to the use of analogue
regulation, in the same way as parameters marked “relay” only apply to relay regulation.
3: Analogue Kp
This is the proportional gain value. Increasing this value gives a more aggressive reaction. Adjusting this value also affects the
integral and derivative output. If Kp needs adjustment without affecting the Ti or Td part, adjust these accordingly.
4: Analogue Ti
Increasing the Ti results in less aggressive integral action.
5: Analogue Td
Increasing the Td gives more aggressive derivative action.
6: Analogue output
Choose the physical internal or external output.
7: Analogue output inverse
Enabling this inverses the output function.
t
Set point
0
100
Result
Output [%]
Direct reg. output
Inverse reg. output
Result of output
• Direct error = SP - PV
• Inverse error = PV - SP
Direct output is used in applications where a rise in analogue output increases the process variable.
Inverse output is used in applications where a rise in analogue output decreases the process variable.
Example explaining direct and indirect regulation:
Typically, heating applications use direct output and cooling applications use inverse output. Imagine a container of water, which
must be kept at a set point of 20 °C at all times. The container can be exposed to temperatures between 0 and 40 °C, hence it is
fitted with both a heating coil and a cooling coil. See the illustrations of this below here.
DESIGNER'S HANDBOOK 4189341275A EN Page 187 of 196
To Next Page
Loading...
