87
11 Appendix
Pulse frequency controller (output is active for X > W and a P control structure)
If the process value X exceeds setpoint W, the P controller will control
proportionally to the control deviation. On going outside the proportional
band, the controller operates with an output level of 100% (maximum
switching frequency).
Special controller functions
The following functions can be activated in this menu:
- Manual mode (activate controller outputs manually), see section 6.6
"MANUAL mode / simulation mode", page 33
- Separate controllers (see below)
- I-component switch-off (see below)
Separate controllers
This function is normally deactivated (factory setting or "No" selection).
In the deactivated state, the software prevents the two controller outputs from
being able to work "against each other". So, for example, it is not possible to
dose acid and lye at the same time.
If the controllers are separate ("Yes" selection), each controller can be freely
configured.
I-component switch-off
This function is normally deactivated (factory setting or "No" selection).
In the deactivated state, the controller works in accordance with general con-
troller theory.
When I-component switch-off is activated ("Yes" selection), the part of the out-
put level that can be traced back to the I-component is set to zero when the
setpoint is reached.
This can be useful with mutual neutralization (acid and lye dosing both pos-
sible) in one treatment tank.
100%
50%
0%
No pulses
50% of pulse frequency
Maximum pulse frequency
Setpoint W
Proportional band X
P
X
P
X - W
0
1
Output level y
Process value X
Summary of Contents for AQUIS 500 CR
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