Table of Contents
Advertisement
OPM223/253
5.4.4
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 in
accordance with field R 237 / R 266 via the current output.
Fig. 27:
The current output characteristic must be extremely monotonic increasing or extremely
monotonic decreasing.
The distance per mA between two table value pairs must be greater than:
• pH: 0.03
• ORP: 5 mV
• Temperature: 0.25 C
The values for the sample characteristic (Fig. 27) are entered in the following table. The
distance per mA can be calculated from Δ signal / Δ mA.
Value pair
1
2
3
First enter the desired current output configuration into the following blank table with a pencil.
Calculate the resulting signal distance per mA to observe the necessary minimum slope. Then
enter the values in the device.
Current outputs
pH
12
10
8
6
0
4
User-defined current output characteristic (example)
Current output 1
pH / mV /
Current
% / C
[mA]
6
4
8
16
12
20
8
12
D I [mA]
Distance
pH / mV /
per mA
% / C
0,166
1,000
Operation
16
20
I [mA]
C07-OPM2x3xx-05-06-00-xx-004.eps
Current output 2
Current
Distance
[mA]
per mA
35
Advertisement
Table of Contents
