Endress+Hauser Liquiline CM44P - Page 88

Operation Liquiline CM44P
88 Endress+Hauser
Source of data Measured value
TU/TS Selection
• Temperature
• Turbidity g/l
(only TU/TS)
• Turbidity FNU
(only TU/TS)
• Turbidity Formazine
(only TU)
• Turbidity solid
(only TU)
TU
Nitrate Selection
• Temperature
• NO3
• NO3-N
Ultrasonic interface Selection
• Temperature
• Interface
• Turbidity
SAC Selection
• Temperature
• SAC
• Transm.
• Absorption
• COD
• BOD
Controller 1 Selection
• Bipolar
(only for current outputs)
• Unipolar+
• Unipolar-
Controller 2
Mathematical functions All the mathematical functions can also be used as a data source and the calculated
value can be used as the measured value.
Outputting the controller manipulated variable via the current output
Unipolar+ Assign to the output to which an actuator that can increase the measured value
is connected. Unipolar- Assign to the output to which an actuator that can decrease the
measured value is connected.
To output the manipulated variable of a two-sided controller, positive manipulated
variables and negative manipulated variables generally have to be output to different
actuators, as most actuators are able to influence the process in one direction only (not in
both). For this purpose, the instrument splits the bipolar manipulated variable y into two
unipolar manipulated variables, y+ and y‐.
Only the two unipolar manipulated variable parts are available for selection for outputting
to modulated relays. If outputting the values via a current output, you also have the
possibility of outputting the bipolar manipulated variable y to one current output only
(split range).
10.4.2 Alarm relay and optional relays
The basic version of the device always has one alarm relay. Additional relays are also
available depending on the version of the device.
The following functions can be output via a relay:
• Limit switch status
• Controller manipulated variable for controlling an actuator
• Diagnostic messages
• Status of a cleaning function in order to control a pump or a valve
You can assign a relay to multiple inputs in order to clean several sensors with just
one cleaning unit, for example.