PFlow Industries P118i, Руководство пользователя

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P118i Ultrasonic Flowmeter and Analyzer
Reversion: 3.0.0 Page 19 of 49
3.1.4 N Method (not commonly used)
With the N method, the sound waves traverse the fluid three times and bounce twice off the pipe walls. It is
suitable for small pipe diameter measurement. The measurement accuracy can be improved by extending the
transit distance with the N method ( uncommonly used ).
3.2 Transducer Installation and Fixing
Transducers can be installed onto the pipe with its magnetic racks. If you need to fasten them, then you can use
the chains to make it firm. Show as below:
3.3 Transducer Mounting Inspection
Confirm the transducer is installed properly by checking the detected signal strength, total transit time, delta time
as well as transit time ratio Key 9.
The "mounting" condition directly influences the flow value accuracy and system long-term operation reliability.
In most instances it is only necessary apply a wide band of sonic coupling compound lengthwise on the face of the
transducer and stick it to the outside pipe wall to get good measurement results. However, the following checks
still need to be carried out in order to ensure a high reliability of the measurement and long-term operation of the
instrument.
3.3.1 Signal Strength
Signal strength (displayed in Signal) indicates a detected strength of the signal both from upstream and
downstream directions. The relevant signal strength is indicated by numbers from 00.0 ~ 99.9. 00.0 represents no
signal detected while 99.9 represents maximum signal strength. Normally, the stronger the signal strength detected,
the better the instrument reliably will be. It will also result in a more stable the measurement value.