Emerson Rosemount FCL, Reference Manual

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c) If you have a Rosemount FCL-02, choose either Live/Continuous or Manual
for Free Cl Correct (free chlorine correction). Live/Continuous means the
transmitter will use the pH measured on the second channel to continuously
correct the chlorine reading for changes in the sample pH. Manual means the
transmitter will use a fixed pH value entered by you to convert the raw
chlorine signal to a ppm reading.
d) If you have a Rosemount FCL-01, Free Cl Correct (free chlorine correction)
will not appear. Instead, enter the desired pH correction value for Manual pH.
The screen summarizes the present configuration for sensor 2 (pH). There are six
items: Measure, Preamp, Sol'n Temp Corr, Resolution, Filter, and Reference Z
(reference impedance). Only four items are shown at a time. To view the remaining
items, scroll to the bottom of the screen and continue scrolling.
6. To make a change move the cursor to the desired line and press ENTER .
A screen appears in which the present setting can be edited.
7. To store the settings, press ENTER .
a) For pH Preamp, choose Analyzer.
b) For pH Reference Z, choose Low.
c) Leave Filter at the default value unless readings are noisy.
For an explanation of terms, see Definitions - chlorine and Definitions - pH/ORP .
8. To return to the main display, press
MENU
and then
EXIT
.
5.6 Configuring temperature related settings
5.6.1 Purpose
This section describes how to do the following:
1. Choose temperature units.
2. Choose automatic or manual temperature correction for membrane permeability.
3. Choose automatic or manual temperature compensation for pH.
4. Enter a temperature for manual temperature compensation.
5.6.2 Definitions - chlorine
Automatic
temperature
correction The free chlorine sensor is a membrane-covered amperometric sensor.
It produces a current directly proportional to the rate of diffusion of free
chlorine through the membrane. The diffusion rate, in turn, depends on
the concentration of free chlorine in the sample and membrane
permeability. Membrane permeability is a function of temperature. As
temperature increases, permeability increases. Thus, an increase in
temperature will cause the sensor current and the transmitter reading
to increase even though the concentration of chlorine remained
constant. In automatic temperature correction, the transmitter uses
Programming the transmitter Reference Manual
May 2019 00809-0100-3412
56 Emerson.com/Rosemount