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2009 Nalco Company
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Technical Help
(630) 305-CHEM
3D TRASAR
5500 - Installation & Operation Manual
Adjusting the conductivity temperature coefficient (TempCoEff)
Calibrated conductivity systems will use a default temperature coefficient to compensate the tem-
perature effect on conductivity. The default temperature coefficient may not fit for your process
water perfectly and may need to be adjusted.
Diagnose the TempCoEff Problem
During operations, you may have an inaccurate temperature coefficient for the system if the follow-
ing are true:
• The output conductivity is accurate after the calibration, and becomes deviated from the true value
as temperature changes, and
• The changes between conductivity and temperature are consistently correlated (i.e. conductivity
always changes in the same manner as temperature increases and
vice versa
).
!
NOTE
: Conductivity fluctuations that do not consistently correlate with tempera-
ture changes may indicate other issues such as probe malfunction, loose wire
connections, etc. Call the Nalco Help Desk for assistance.
Adjust the TempCoEff value
To adjust the temperature coefficient of your conductivity detection system:
• Connect your Configurator with the 3D Controller.
• Using the pull down Menu, choose Controller – Tools – Adjust Cond Probe Temp Coeff.
• In the dialogue box, choose “Get Values” button, then fill in the accurate conductivity value obtained
from a calibrated conductivity meter.
• Choose “Calculate” button, the new Temp coefficient should be in the field.
• Choose Upload
!
NOTE
: To make an accurate temperature coefficient change, make sure the
temperature of the process water is less than 71
o
F (22
o
C) or greater than
83
o
F
(28
o
C)
.
The best time to perform this adjustment is when the process water temperature is in a stable state
at which the temperature is different from the temperature when a 2-point calibration was performed
(avoid performing a temperature coefficient adjustment if process water temperature is quickly
changing).
