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MAN-147-0018-A
Installation of the magnetic type LNS sensor:
The logger uses the sensor to listen to sounds produced from the pipe network. It then
uses special algorithms to judge whether a leak is likely to be present nearby.
The audio sensor within the LNS unit is
attached to the outside of the pipe network
for use, usually using a magnet to attach it
to a metal pipe asset (hydrant or valve) within
a chamber. Refer to Figure 16.
The sensor should ideally be attached to an
upper surface of the asset, with the sensor
facing downwards. (This reduces the risk of
the sensor falling).
Prior to installing the sensor, clean the asset
attachment point and remove any rust from
it, using a wire brush; this ensures a good
contact will be made with the pipe (for
conducting sound).
Then connect the sensor cable to the logger.
Installation of the Hydrophone-2 sensor:
The audio sensor within the Hydrophone-2 unit
connects directly to the water inside the pipe via an
access point, such as a hydrant (see Figure 17). This
gives it a longer range of operation than the LNS,
especially in plastic pipes.
Installing the unit into the water network can be a
dangerous operation unless carried out correctly.
Refer to the Hydrophone-2 user-guide (MAN-165-0001)
for installation and use details.
Behaviour of Logger and Server:
The use of a Leak-Noise sensor or Hydrophone can cause some changes (additions) to
the logger’s pattern of behaviour. This section provides a summary of the loggers use of
the sensors; For a detailed explanation, refer to the P with Hydrophone-2
user-guide (MAN-148-0007).
The output from the logger will include a variety of parameters, each of which will be a
datapoint channel.
The leak detection parameters will include:
•
Level
•
Spread
•
Leak / No-leak judgement
Figure 17. Example of a
Hydrophone-2 installation
LNS
Sensor
Top of
asset
(e.g., Tap
for a valve)
Clean and
rust-free
surface
Magnet
Figure 16. Example of LNS installation
