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LMT10 0 A N D LMT 20 0 |
M AG N E TOS T R I C T I V E L E V EL T R A N SM I T T ER S | FF O I/L M T 10 0/ 2 0 0/FF - EN R E V. A
Troubleshooting using waveform display
Error
Possible Cause
Suggested Action
The presence of dashed lines in place
of the process variable value
Indicates that a valid level cannot be detected
• Navigate to the waveform screen to verify the presence of a
signal with amplitude equal or close to 2V unless the probe
length exceeds 20 feet
• Verify that the float is not damaged
• Make sure the blanking value does not exceed the signal to be
detected
• Make sure the threshold is not set too high
Small amplitude of the signal
Degradation of the signal amplitude could be an
indication of other underlying problems like
weakening of the magnetic flux of the float or
sensor deterioration issues
If the signal is present but the amplitude does not cross the
threshold line, verify that:
• The float is present and not damaged
• The strength of the magnetic field of the float is correct
If the sensor has deteriorated or been damaged, navigate to
the pulse width parameter to change it to a larger value This
temporary remedy might give enough time to perform a
deeper evaluation of the instrument and replace defective
components
The float is moving along the probe
as well as the signal, but the level
does not change
Artifacts could be created as result of magnetic
materials or components in the proximity of the
probe
Check for artifacts with an amplitude larger than the threshold
value located on the left side of the signal Adjust the blanking
to bypass the artifacts seen in the waveform screen
