TF1100-EH transit-time handheld flowmeter manual
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nearby. Try to relocate the flow meter to a new place where the interference can be
reduced.
(2)
Bad sonic coupling for the transducers with the pipe. Try to apply more coupler or clean
the surface, etc.
(3)
Pipes are difficult to be measured. Relocation is recommended.
2.8.3 TOTAL TRANSIT TIME AND DELTA TIME
The numbers displayed on menu window M93 are called total transit time and delta time
respectively. They are the primitive data for the instrument to calculate the flow rate inside
the pipe. So the flow rate indication will vary accordingly with the total time and delta time.
The total transit time should remain stable or vary little.
If the delta time fluctuates higher than 20%, it means there are certain kinds of problems with
the transducer installation.
2.8.4 TIME RATIO BETWEEN THE MEASURED TOTAL TRANSIT
TIME AND THE CALCULATED TIME (M91)
This ratio would be used to check the transducer installation. If the pipe parameters are
entered correctly and the transducers are installed properly, the value for this ratio (M91)
should be in the range of 100±3. If this range is exceeded, the user should check:
(1)
If the pipe parameters are correctly entered.
(2)
If the actual spacing of the transducers is right and the same as what the window M25
shows.
(3)
If the transducers are installed properly in the right directions.
(4)
If the mounting location is good and if the pipe has changed shape or if there is too much
fouling inside the pipes
(5)
Other poor conditions
