GE PanaFlow HT User Manual page 87

E15
E6
E5
E4
E3
E2
E1
PanaFlow HT User's Manual
Table 5: Flow Error String (cont.)
ActiveTw
CycleSkip
Amplitude
SignalQuality
VelocityRange
SoundSpeed
SNR
Chapter 4. Error Codes and Troubleshooting
E15 indicates an error with the active Tw
measurement. This may be caused by a transducer
error, a parameter programming error, or extreme
process temperatures. The error means that the
measurement of how long it is taking the ultrasonic
signal to pass through the bundled waveguide is
outside reasonable limits.
E6 indicates that a cycle skip has occurred in the
signal processing measurement. This is usually due to
poor signal integrity, possibly because of bubbles in
the pipeline, sound absorption by very viscous fluids,
or cavitation.
E5 indicates an amplitude error in the signal
processing measurement. The signal amplitude is
either excessively high or low. This is also due to poor
signal integrity, much like an E6 error.
E4 indicates a Signal Quality error. This means the
signal shape, upstream to downstream reciprocity, or
signal correlation value is poor. The cause is usually
the same as E6 or E5.
E3 is a velocity range error, meaning that the
calculated velocity is outside the velocity limits
defined for this application. The velocity we are
measuring is not reasonable for the fluid and pipe size
programmed in the data set. This could be a
programming error, a poor signal, or an actual flow
condition that is unexpectedly high in the positive or
negative direction.
E2 is a sound speed error. One benefit of ultrasonic
flow measurement is that the process can determine
the sound speed of the fluid. If this sound speed is
beyond the limits set for the programmed application,
an E2 error is set. This can alert the operator that the
wrong fluid is in the pipe, or that the program
parameters are out of date. It may also occur if signal
quality is poor.
E1 indicates a low signal to noise ratio (SNR). This
means the flowmeter is not getting very much acoustic
signal from the process. This could be due to bubbles
or other fluid conditions, an empty pipe, or other
possible causes that are listed in the Diagnostics
section.
77