User's Manual

35
Calculate Velocity
Press 8(Calc Vel) After stopping correlating the option to calculate velocity appears. A
velocity check gives a more accurate velocity of the pipe to be correlated instead of using the
default velocity value.
To calculate velocity a leak must be present, either real or induced. The leak can either be
between the sensors called an “In Bracket” check or outside of the sensors called an “Out of
Bracket” check. Unlike correlation, where the more central the leak is positioned between the
sensors, the more accurate the result. A velocity check requires the leak to be positioned
closer to one of the sensors to create a larger time delay.
The procedure for a velocity check is to position your sensors as described above. Induce
your leak or use the real leak. Correlate as normal entering the correct pipe data. After a good
correlation peak, stop correlating and press 8(Calc vel). The screen below will be displayed.
Enter the position of the leak from the RED Out Station.
If the leak is “In Bracket” between the sensors, then enter the distance from the leak to the
RED sensor. (In this example 92.7m)
If the leak is “Out of Bracket” to the left of the RED sensor, then enter the distance 0
If the leak is “Out of Bracket” to the right of the second sensor, then enter the distance
between the RED sensor and second sensor.