Dynasonics TFXM Series Ultrasonic Multi-Channel Flow Meter - Manual (Page 87)

Rev. 8/02 -5. 5- TFXM
Difference Flow Meter
The difference of two pipes can be utilized to measure the flow in
two pipes and calculate the flow rate in a third trunk line in a pip-
ing system. (The difference meter can also be applied to two
ends of a piping system to display an alarm to leak between the
two measuring points.) Apply a coefficient of +1.00 to one chan-
nel and a coefficient of –1.00 to the second channel. The sum of
the two manipulated values will be the difference in the flow rates.
See Figure 5.4.
Coefficients for measurement channels can also be established
on the TFXM keypad in the AUX Com Port Menu.
MULTICHANNEL OPERATION
Difference
Configuration
Figure 5.4
Subtraction Flow Measurement
Setting Coeffi-
cients on the
Keypad