YSI IQ S ENSOR N ET System 182 - Manual (Page 120)

Outputs System 182
6 - 30 ba76022e01 12/2011
Within the proportional band, a concentration increase by 1 mg/l
causes a decrease of the current output by 1 mA. If, for example, the
measured concentration is 5 mg/l, 11 mA are output:
The highest concentration with which the controller works within the
proportional band is 8 mg/l (corresponding to Imin = 8 mA), the lowest
one is 2 mg/l (corresponding to Imax = 14 mA).
Settings
( )
mg/l mg/l
mg/l
mA
1 mA 12 I
Controller
5 4 − ⋅ + =
( )
mA 11 mg/l 1
mg/l
mA
1 mA 12 I
Controller
= − ⋅ + =
Setting Selection/Values Explanation
Measured variable Main variable
Adjoining variable Main variable
designates the actual
measured parameter of
the sensor (e.g. pH,
oxygen, etc.).
Adjoining variable
designates an
additional measured
parameter (e.g.
temperature).
Nominal value within the measuring
range (sensor-
dependent) Nominal value the
measured value is
regulated to
Xp 5 ... 100 %
-5 ... -100 %
of the measuring
range Proportional band of
the controller.
Negative values result
in a positive
characteristic curve.
Imin 0 ... 20 mA Lower current limitation
*
Imax 0 ... 20 mA Upper current limitation
*
* Note:
Spacing between Imin
and Imax:
at least 5 mA