TurbiTechw² LR Instruction Manual
12 Sensor Faults
12.1 Unstable reading on controller
The following can cause an unstable display value:
•
Material (rag, weed, etc.) caught inside the flowcell (LR) and affecting the measuring system -
remove sensor, manually clean and re-install.
•
Turbulence (caused by high flow, aeration etc.) in the solution being measured - increase the level of
damping on the 7300w² Monitor.
•
Bad connection in the sensor cable - check all connections are secured.
12.2 Error Codes from 7300w² Monitor
The 7300w² Monitor will provide a number of error codes, the majority are generated by and stored in
the sensor. Some messages are warnings, such as Clean In Progress which do not require any action.
12.2.1 Input High Limit/Low Limit
This indicates that the measured value is outside the normal operating limits of the sensor. This could
be caused by sensor fouling but can also indicate a genuine failure of the optical components.
The following action is recommended:
1. Clean the optical surface of the sensor by hand
2. Place the sensor in a sample (alternatively place an object in front of the optics.
At each stage observe the behaviour of the displayed value. If the error message clears then it is
possible that the problem was caused by fouling or by the presence of an object in the sensors optical
path.
If the problem returns when the sensor is returned to it's normal location, it is worth checking the
Suspended Solids/Turbidity present in the sample against the specified range of the sensor. It is
possible that the nature of the application has changed.
If the problem persists please contact Partech or your local representative for further guidance.
12.2.2 Over range/Under range
This indicates that the sensor is receiving a valid measured value that is outside the limits of the
measurement configuration. i.e 1,000 NTU when the display range has been set to 500 NTU.
Firstly check that the plant is working normally and that the sensor has not become damaged or
fouled.
If the sensor is working correctly and the site is operating normally then it may be necessary to change
the configuration of the measurement. This is explain earlier in this manual.
Page 28 of 34
225769IM - Issue - 05 Issue Date 30/04/2019
