LRF-3000H Handheld Ultrasonic Flowmeter
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free of excessive corrosion or scaling.
4.
Transducer Installation
4.1.
Installing the Transducers
Before installing the transducers, clean the pipe surface where the transducers are to be mounted.
Remove any rust, scale or loose paint and make a smooth surface. Apply a wide band of sonic coupling
compound down the center of the face of each transducer as well as on the pipe surface, and then attach
the transducers to the pipe with the straps provided and tighten them securely.
Note:
1. The two transducers should be mounted at the pipe’s centerline on horizontal pipes. Make sure that the
transducer mounting direction is parallel with the flow.
2. During the installation, there should be no air bubbles or particles between the transducer and the pipe
wall. On horizontal pipes, the transducers should be mounted in the 3 o’clock and 9 o’clock positions of
the pipe section in order to avoid any air bubbles inside the top portion of the pipe.
3. Refer to Transducer Mounting on Menu 25.
4. If the transducers cannot be mounted horizontally symmetrically due to limitation of the local
installation conditions, it may be necessary to mount the transducers at a location where there is a
guaranteed full pipe condition (the pipe is always full of liquid).
4.1.1.
Transducer Mounting Methods
Four transducer mounting methods are available. They are respectively: V method, Z method and N
method . The V method is primarily used on small diameter pipes (DN100~300mm, 4”~12”). The Z
method is used in applications where the V method cannot work due to poor signal or no signal detected.
In addition, the Z method generally works better on larger diameter pipes (over DN300mm, 12”) or cast
iron pipes.
The N method is an uncommonly used method. It is used on smaller diameter pipes (below DN50mm,
2”).
4.1.2.
V Method
The V method is considered as the standard method. It usually gives a more accurate reading and is used
on pipe diameters ranging from 50mm to 400mm (2”~16”) approximately. Also, it is convenient to use,
but still requires proper installation of the transducer, contact on the pipe at the pipe’s centerline and
equal spacing on either side of the centerline.
Downstream Transducer
Upstream Transducer
Flow
Transducer Space
Flow
Side View
Top View
Section
Pipe Strap
Transducer
