ADS Environmental Services Eureka2R QR 775019 A1 - Manual (Page 30)

ADS Eureka2R Leak Noise Correlator User Manual
26
Survey
This mode provides a quick overview of the leak noise and automatically
restores the pipe details to the default conditions. This is ideal for applications
where a leak is suspected because it allows for the identification of any peaks
in the noise spectrum while, for example, the sensors are reading successive
lengths of pipe.
Leak Locate
Leak Locate is the standard mode of operation through which you can change
the pipe details as required and use functions, such as Go to Peak, on the
main Correlate screen.
Measure Velocity
Measure Velocity allows you to measure the actual velocity of sound in the
pipe(s). However, there must be a leak in the pipe line at a known position,
commonly produced by opening a hydrant. Two main options are available
for the leak position: Out of Brackets or Towards Red/ Towards Blue.
Out of Brackets means the intentional leak exists at one of the sensor positions
or beyond the length bracketed by the sensors, at either end.
Towards Red or Towards Blue means the leak is reasonably close to the Red
or Blue sensor, within the bracketed length. To ensure accuracy, the distance
from the sensor should be less than one third of the total pipe length.
This technique involves entering the pipe material and length measured with
the usual method, selecting Mode > Measure Velocity, and then selecting
from Out of Brackets/Towards Red/Towards Blue. When selecting
Towards Red/Towards Blue, enter the distance from the intentional leak to
the sensor.
Perform correlation in the usual manner, using zoom if necessary to locate the
exact peak. Note that an over-range area always exists beyond the ends of the
pipe. This is to cover conditions where the nominal velocity is significantly
inaccurate, but the correlation in this area is valid.
After calculating the velocity value, hit the Leak Locate button. At the
prompt, choose whether to use the velocity value instead of the default by
selecting one of the two soft keys labeled Yes and No. Then, turning off the
manufactured leak allows for location of the unknown leak with improved
accuracy.
Note: Measuring velocity using this method does not account for
more than one pipe material because it can only measure the average
velocity over the given pipe length.