521-OM0108.88
Copyright
2009 Nalco Company
4-21
Technical Help
(630) 305-CHEM
3D TRASAR
5500 - Installation & Operation Manual
4.10.5 ORP Calibration Screens
Select
ORP
from the
Calibration
menu and follow screen directions to per-
form calibration.
A
1-point calibration
utilizes the system water as the calibration point.
It is best used to fine-tune your calibration to compensate for minor drift-
ing.
A
2-point calibration
is best utilized when installing a new probe or if a
major error has developed due to excessive fouling or probe degradation.
Control
Settings
Alarm
Settings
Preferences
System
Info
Network
Information
Manual
Relay
Actions
Menu
Alarms
For a 1-point calibration
STEP 1
- Leave probe in tee with water flowing. Select
1-point
calibration.
STEP 2
- Using a handheld instrument of known accuracy and calibration,
sample the process water and determine the ORP value.
STEP 3
- Enter this value.
For a 2-point calibration
STEP 1
- Select a
2-point
calibration.
STEP 2
- Close the sample inlet, lower sensor outlet, and 3-way valves.
STEP 3
- Remove the ORP probe the tee.
STEP 4
- Swirl the probe in a beaker of clean, fresh ORP 200 mV buffer
solution
(P/N 460-S0932A.75)
. Press
Continue
.
STEP 5
- After prompt, rinse probe well in clean DI water and wipe clean.
STEP 6
- Swirl probe in a beaker of clean, fresh 600 mV buffer solution
(P/N 460-S0933A.75)
. Press
Continue
.
STEP 7
- After successful calibration reinstall probe and open valves.
!
If probe calibration is unsuccessful, check standards, wiring
connections, or handheld ORP meter for accuracy. Clean the
ORP probe tip and recalibrate.