Hach Polymentron 9500 Basic User Manual page 26

Problem
Display is lit but shows no characters or
characters are faint or blurry.
Controller will not power up, or powers up
intermittently
Network or sensor module not recognized
Sensor not recognized
Device Missing error message appears
26 English
Resolution
Adjust the display contrast
Make sure protective film has been removed from display.
Clean the outside of the controller, including the display screen.
Make sure the AC power connections are properly terminated in
the controller.
Make sure the power strip, line power, wall plug are all properly
plugged in.
Contact Technical Support
Make sure the module is properly installed.
Make sure the module selector switch is set to the proper
number.
Remove sensor module and install the module into the second
analog slot. Apply power to the controller and allow the controller
to perform a device scan.
Contact Technical Support.
If the sensor and a corresponding module is installed in the
controller, refer to the instructions supplied with the Network or
Sensor Module.
Contact Technical Support
Perform a Device Scan from the Test/Maintenance menu.
Power cycle the controller