Configuring Temperature Related Settings; Purpose; Definitions - Emerson Rosemount MCL-220 Manual

4.
5.
6.
6.6

Configuring temperature related settings

6.6.1

Purpose

This section describes how to do the following:
1.
2.
3.
6.6.2

Definitions

Automatic
temperature
correction
Manual
temperature
correction
Instruction Manual
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.
To store the setting, press ENTER.
a. For Measurement, choose Chloramine.
b. Leave Filter at the default value unless readings are noisy.
To return to the main display, press MENU and then EXIT.
Choose temperature units.
Choose automatic or manual temperature correction for membrane permeability.
Enter a temperature for manual temperature compensation.
The monochloramine sensor is a membrane-covered amperometric
sensor. It produces a current directly proportional to the rate of
diffusion of monochloramine through the membrane. The diffusion
rate, in turn, depends on the concentration of monochloramine 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 monochloramine remained constant. In automatic
temperature correction, the transmitter uses the temperature
measured by the sensor to continuously correct for changes in
membrane permeability.
In manual temperature correction, the transmitter uses the
temperature you enter for correction. It does not use the actual process
temperature. Do not use manual temperature correction unless the
Programming the transmitter
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