Rosemount 3107, Справочное руководство

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Reference Manual
00809-0200-4841, Rev BA
Section 3: Installation
December 2014
Section 3: Installation 14
When setting the bottom reference on a ‘V’ notch weir, it is important the true invert is used and
not the meniscus level (
Figure 3-5 ).
Figure 3-5. Bottom reference of a ‘V’ notch weir
A. Transmitter bottom reference (i.e. true invert)
B. Meniscus level
Positioning of the remote temperature sensor (3108 only)
The Rosemount 3108 transmitter has a factory fitted remote temperature sensor. The
temperature sensor is enclosed in a M8 x 1.5 threaded stainless steel body.
Figure 3-6 and Figure 3-7 on page 15 show two typical arrangements for installing the
temperature sensor in an open or enclosed chamber. The sensor may be installed in a suitable
plastic conduit box and clamped in place using a suitable compression type cable gland.
1. Open weir chamber ( Figure 3-6 on page 15 )
Mount the remote temperature sensor so that it is representative of the mean air
temperature in the chamber and is in a shaded area away from direct sunlight and solar
radiation.
2. Enclosed or partially covered flume chamber ( Figure 3-7 on page 15 )
Mount the remote temperature sensor in the approach channel, in a shaded area away
from direct sunlight and solar radiation. In
Figure 3-7 on page 15 , the sensor is partially
covered by grating which helps prevent solar gain. (Full grating is removed for clarity.)
The temperature sensor should be positioned in the weir chamber or flume approach channel so
the average air temperature can be accurately measured. The temperature sensor
must be
protected at all times from direct sunlight and any radiated heat.
In extreme high temperatures, for the best accuracy and stability of level measurement reading,
the transmitter should be shrouded to prevent the incidence of direct sunlight and solar
radiation. If the flow structure permits, mount the transmitter within the flow channel or
chamber.
B
A