S/Controller Menu - Hach POLYMETRON 8362 User Manual

Transmitter 9135 - pH measurement in pure water
0.0 pH
-1500 mV

S/CONTROLLER Menu

The built-in proportional
controller P. The controller output Y activates the limit
switch relays. Y value may correspond to a control by
impulse or a control by frequency. The Y value is
determined by the parameters below :
•
A setpoint (W) : corresponds to the pH value to
control.
•
Within this neutral band the control element (valve,
dosing pump) is always inactive.
•
A proportional band (XP) : represents the
regulation slope. A XP value equal to 100% is
defined as a Y controlling value of 100% for a 5 pH
(or 1000 V in redox) drift according to the neutral
zone extremity.
•
A power factor (Exponent) : which calculates a
controlling value from a lineary (exponent = 1) or
an exponential function.
The value of Y in pH corresponds to the equation
below :
Y
Y value is represented as follows :
controller,
[ pH - (W +
100
= *
XP
Y
(XP=50%)
100%
50%
0%
2.5
0.0
W
Z N
abbreviation
Exponent
ZN
] )
2
5
(XP=100%)
(XP=200%)
5.0 pH
14.0 pH
+1500 mV
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