Endress+Hauser Topclean S CPC30, Руководство по эксплуатации

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6 Commissioning Topclean S
74 Hauser
6.6.12 Set up 2 – Controller settings
Requirements for controller settings:
You have carried out the following settings which are necessary for controller configuration
either in the First start up, page 51 or on the appropriate menu page.
• Set the number of relays available to the controller (field "Contact functions", page 52 or page 61).
• Define current output
2 as continuous controller (when controling the actuator via a 20 mA
interface, field "Select current output parameter", page 53 or page 59).
If you have not yet made the settings, please do this before configuring the controller.
!
Note!
•
Danger of data loss.
– If you assign the relays which are used by the controller with another function (field "Contact
functions", page 61), the complete controller settings are reset to the default values.
– If you change the function of current output 2 from "controller" to another function, the
complete controller settings are reset to the default values.
• If you change the relay assignment for the controller in field "Contact functions" (page 61), you
must use the controller menu to reassign all the functions selected there to a relay.
Example:
– Relays 4 and 5 are assigned to the controller.
– You change the controller assignment to relays 5 and 6 (number of relays remains 2).
–
No data loss, providing the number of assigned relays is not reduced!
• Relays 3, 4 and 5 are located on the additional plug-in card. If you want/have to remove this card
from the device, check whether you have used one of these relays for the controller function. If
so, change the controller settings before removing the second card, so that the controller works
with the basic device equipment (relays 1 and 2). Otherwise, you cannot use the controller
function as long as the additional card is not plugged into the device.
Definition of terms
Actuators: Valves, gate valves, pumps and similar
Acid/base: The terms "acid" and "base" used in the menu are used here relating to the direction of action.
Acid = Dosing medium which lowers the pH value.
Base = Dosing medium which raises the pH value.
Example : A fluid (pH value 14) needs to be brought to the reference value of pH 12 with a base (pH
value 9). In the "Dosing" menu, choose "Acid" as the addition of this dosing medium will lower the
pH value of the fluid.
Process: The control or the process (to simplify matters this will, from henceforth, be referred to as the
"process") can be differentiated on account of their different features:
Direction of action, one or
two-sided: One-sided control only works in one of two directions. This can be, for example, a neutralisation
process in which a dosing medium is used (acid or base).
With a two-sided process, control can generally work in two-directions (use of acid and base). This
means that you can both increase and decrease the value of the actuating variable (here = pH value).
To implement this, the set reference value of your process must lie between the pH values of the
two dosing media.
P controller Used for simple linear control purposes with small system deviations. Where major changes are to
be controlled, overshooting may occur. In addition, a lasting control deviation is to be expected.
PI controller Used for control systems where overshooting is to be avoided and no lasting control deviation
should occur.
PD controller Used for processes that require quick changes and where peaks are to be corrected.