Mounting The Transmitter Above The Liquid Surface; Mounting Bracket - Emerson Rosemount Ultrasonic 3107 Quick Start Manual

Quick Start Guide
Obstructions in the tank, or well, may generate echoes which can be confused with

the real liquid surface echo. Obstructions within the beam angle generate strong
false echoes. Wherever possible, the transmitter should be positioned to avoid
false echoes.
To avoid detecting unwanted objects in the tank or well, it is advisable to maintain

a distance of at least 1.3 in. from the center line of the transmitter for every foot
(11 cm per meter) range to the obstruction. (See
No false echoes are generated if the transmitter is located near the side of the tank

or well and the wall is smooth and free of protrusions. However, there will still be a
reduction in the echo size. It is recommended that the transmitter be mounted no
closer than 12 in. (0,3 m) to the wall to avoid a large reduction in the echo size
If the transmitter is mounted in an enclosed tank with a domed top, avoid

mounting the transmitter in the center of the tank roof because this could act as a
parabolic reflector and create unwanted echoes
Avoid applications where heavy condensation could form on the transmitter face

If the transmitter is mounted in a stand-off or nozzle, the transmitter face should

protrude at least 0.2 in. (5 mm) into the tank
If the transmitter is used in environments where direct sunlight can cause high

surface temperatures on exposed instruments, a sun-shade is recommended

Mounting the transmitter above the liquid surface

A 1 in. thread is provided to mount the transmitter
or
BSPP (G1) NPT

Mounting bracket

The transmitter is supplied with a purpose made 316 Stainless Steel mounting bracket
(Figure 4) which should be used to mount the transmitter over the liquid surface.
The bracket is designed to fit over the threaded neck of the transmitter and is retained
by a locknut
Use a or
chain
ensure that the transmitter will hang perpendicular to the liquid surface.
Never suspend the transmitter by the cable
wire is corrosion resistant to the liquids and any vapors present.
The bracket may be bolted to a suitable cross member above the liquid surface. Ensure
the transmitter is perpendicular to the surface to maximise the return echo size.
Figure 4. Mounting bracket
A. 1-in. mounting thread
6
, and is marked below the mounting thread.
through the hole provided in the bracket, which is shaped to
wire
A
Figure 5 on page
(Figure 4). The thread form is either
.
Check that the material of the chain or
July 2016
7).