Endress+Hauser Liquisys M CLM253 - Current Outputs

Liquisys M CLM223/253 Commissioning
Endress+Hauser 45
7.4.4 Current outputs
Use the "Current output" function group to configure the individual outputs. You can enter
either a linear characteristic (O3 (1)) or a user-defined current output characteristic in
conjunction with the Plus Package (O3 (3)). Exception: if you have chosen a "continuous
controller" for current output 2, you cannot enter a user-defined current output
characteristic for this current output.
In addition, you can also simulate a current output value (O3 (2)) to check the current
outputs.
If a second current output is present, you can output the controller actuating variable via
the current output in accordance with field R237/O2.
1500
1000
2000
500
0 4 8 12 16 20
I [mA]
D I [mA]
D Signal
[mS/cm]c
A0008943
 27 User-defined current output characteristic (example)
The current output characteristic must increase or decrease very monotonically.
The distance per mA between two table value pairs must be greater than:
• Conductivity: 0.5 % of measuring range
• Temperature: 0.25 °C
The values for the sample characteristic →  27 are entered in the following table. The
distance per mA is calculated from Δ signal / Δ mA.
Current output 1 Current output 2
Value pair [mS/cm]
[%] [°C]
Current
[mA]
Distance
per mA
[mS/cm]
[%] [°C]
Current
[mA]
Distance
per mA
1 500 4
2 1000 16 41.66
3 2000 20 250