21
Reference Manual
00809-0100-4530, Rev DD
May 2016
Flange connection on nozzles
Figure 3-2. Mounting in Nozzles
The transmitter can be mounted in nozzles by using an appropriate flange. The nozzle sizes
given in
show the recommended dimensions. For small nozzles, it may be
necessary to increase the Hold Off Distance/Upper Null Zone (UNZ) to reduce the
measuring range in the upper part of the tank. Amplitude Threshold adjustments may also
be needed in this case. A Trim Near Zone is recommended in most nozzle installations, for
example, when there are disturbing obstacles in the near zone.
See
.
Note
The probe should not contact the nozzle, with the exception of the Coaxial Probe. If the
nozzle diameter is less than recommended, the measuring range may be reduced.
Table 3-1. Nozzle Considerations
Single
(rigid/segmented/flexible)
Coaxial
Twin
(rigid/flexible)
Recommended
nozzle diameter (D)
6 in. (150 mm)
> probe diameter
4 in. (100 mm)
Minimum nozzle
diameter (D)
(1)
1.
The Trim Near Zone (TNZ) function may be necessary or an Hold Off Distance/Upper Null Zone (UNZ) setup may be
required to mask the nozzle.
2 in. (50 mm)
> probe diameter
2 in. (50 mm)
Recommended
nozzle height (H)
(2)
2.
Longer nozzles may be used in certain applications. Consult your local Emerson Process Management representative for
details.
4 in. (100 mm)
+ nozzle diameter
(3)
3.
For nozzles taller than 4 in. (100 mm), the Long Stud version is recommended (option code LS) to prevent the flexible
portion from touching the edge of the nozzle.
N/A
4 in. (100 mm)
+ nozzle diameter
Avoid nozzles with reducer
(unless using coaxial probe).
Hold Off Distance/UNZ
H
D
Make sure the nozzle does
not extend into the tank.