Regal RH40, Руководство пользователя

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The flow meter will operate well when the signal strength ranges from 500 to 999 . Regardless of the
functioning range, higher signal strength is always desirable
—the higher the number, the more reliable
and accurate the results will be. The following methods are recommended to obtain strong signals:
1) Make sure the pipe is in excellent condition. Polish the outer surface of the pipe and apply more
couplant between the pipe and transducers.
2)
Carefully adjust the position of the two transducers, both vertically and horizontally. Check the
signal strength after each movement. Stop at the position where the signal strength reaches a
maximum. Be sure to check the transducer spacing to make sure it is still the same or very close
to the figure displayed in S1, Step 5 (see Section §2.6).
3)
If the current location of the transducers provides a signal strength that is lower than 700, try
relocating into a location in more favorable condition.
§3.4.B Signal Quality
Signal quality is indicated as the Q value for this instrument. This value can be seen on the main menu. A
higher Q value means a higher Signal to Noise Ratio (SNR). Higher signal quality yields a higher degree
of accuracy. Under normal pipe conditions, the Q value should be in the range of 60 to 90 . A higher
quality is always more desirable.
Causes for a low Q value may be:

Interference from other instruments and devices nearby, such as a power frequency transverter,
which could cause strong interference. If possible, relocate the flow meter to a location where
interference is minimal.

Bad sonic coupling between the transducers and the pipe. If the Q value is not in the desired
range, we recommend polishing the pipe surface again. It is important to clean the surface after
polishing. We also recommend adding more couplant. Finally, the pipe needs to be in the best
condition possible.

The selected pipe section is not conducive to accurate measurement. In some cases, the pipe
material causes this problem with signal quality. For example, carbon steel pipes frequently
feature corroded pipe sections, which would change pipe wall thickness values. In this case, we
recommend using the Z-method for transducer installation. Increase or decrease the spacing
between the transducers until the ratio is 100±3. See section §3.4.D for more details. The user
may also move the transducers to a pipe section that is in more favorable condition.