Rosemount 3107, Reference Manual

Page: 22 / 148

Reference Manual
00809-0200-4841, Rev BA
Section 3: Installation
December 2014
Section 3: Installation 12
Bracket mounting
The transmitter is supplied with a purpose made 316 Stainless Steel mounting bracket 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 (see
“1-in. NPT/BSPP
bracket kits” on page 117 for dimensions).
Use a chain or wire through the hole provided in the bracket, which is shaped to ensure that the
transmitter will hang perpendicular to the liquid surface. Check that the material of the chain or
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 that the
transmitter is
perpendicular to the liquid surface to maximise the return echo size.
Note

Check that the maximum liquid level will not enter the 12 in. (0.3 m) blanking zone of
the transmitter.

To help with alignment, the echo size (signal strength) can be indicated on the
Rosemount 3490 Series Control Unit or a Field Communicator.
Flange mounting
The instrument (accessory) flanges supplied by Emerson are manufactured from PVC and are a
full face design. Care must be taken when installing to a raised face mating flange on the tank or
vessel to prevent distortion of the PVC flange by over-tightening the bolts. See
“Spare parts and
accessories” on page 120 for part numbers.
Mounting from a conduit
The 3107 and the 3108 can be mounted from a conduit using the optional adaptor
(03107-7003-0003 and 03107-7003-1004). See
“Spare parts and accessories” on page 120 .
3.3.4 Open channel flow installations
There are normally two distinct parts to an open channel flow measurement system; the
primary element (flow structure) and the secondary element (Head measurement instrumenta-
tion). For accurate open channel flow measurement, both parts of the system must be correctly
installed. This section explains the important parts of installing the transmitter (secondary
element). The flow structure (primary element) installation can be referenced in the British
(BS3680) or ISO International standards.
Note

The transmitter should be free from a situation where it is likely to 'drown' (refer to the
relevant standard for further information)

The Rosemount 3108 has a factory-fitted Remote Temperature Sensor.
See
“Positioning of the remote temperature sensor (3108 only)” on page 14 .

For some installations, the use of a calibration device is mandatory. Emerson offers the
Rosemount Head Verification Device (HVD) for this purpose. See
“Spare parts and
accessories” on page 120 for further information.