ADS Environmental Services Eureka2R QR 775019 A1 - Manual (Page 17)

ADS Eureka2R Leak Noise Correlator User Manual
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Sensors
The sensors detect the leak noise and convert it to an electrical signal. Two
types of sensors are available: an accelerometer and a hydrophone.
Accelerometers, which mount magnetically to the external surface of the pipe,
detect noise transmitted through the wall of the pipe. Hydrophones, which
mount inside the pipe for direct contact with the water, are more sensitive than
accelerometers and are preferable for investigations involving low leak noise
level conditions (such as distant leak sites), plastic piping, or large diameter
pipes. Hydrants provide useful access for this purpose.
Attaching Accelerometers to Pipes
The accelerometers supplied with Eureka2R have an integrated magnet for
easy attachment to ferrous pipes. For non-ferrous pipes, clamp the
accelerometer to ensure contact between the base of the sensor and the pipe.
Another option involves attaching a set of mechanical grips to the non-
magnetic valve stem and then attaching the sensor with its magnetic base to
the grip.
Note: The accelerometer requires a good acoustic coupling to the
pipe; therefore, mount it to as smooth a surface as possible.
Accelerometer attached to valve body
Make sure the cable does not pull on the accelerometer because this can affect
the effectiveness of the acoustic coupling. ADS recommends placing any
spare cable into the chamber to minimize the possible effects of wind noise.
Assess the site conditions to determine whether to connect the accelerometer
directly to Eureka2R or to the radio transmitter.