Emerson Rosemount X-well 648, Справочное руководство

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Reference Manual
00809-0200-4648, Rev BB
Installation
July 2016
Installation
3.5 Physical installation
When selecting an installation location and position, consider the need for access to the
mesh network, transmitter, and power module compartment for ease of power module
replacement.
Verify the operating atmosphere of the transmitter is consistent with the appropriate
hazardous locations certifications.
The Rosemount 648 Wireless can be installed in one of two configurations: Direct Mount,
where the sensor is connected directly to the Rosemount 648 Wireless housing’s conduit
entry, or Remote Mount, where the sensor is mounted separate from the Rosemount 648
Wireless housing, then connected to the Rosemount 648 Wireless via conduit. Select the
installation sequence that corresponds to the mounting configuration.
Figure 3-4 provides an example of the relationship between transmitter housing
temperature rise and extension length.
Figure 3-4. Rosemount 648 Wireless Connection Head Temperature Rise vs. Extension
Length
Example
The transmitter specification limit is 85 °C. If the ambient temperature is 55 °C and the max
process temperature to be measured is 815 °C, the maximum permissible connection head
temperature rise is the transmitter specification limit minus the ambient temperature
(moves 85 to 55 °C), or 30 °C.
In this case, a 5-in. extension meets this requirement, but a 6-in. extension provides an
additional margin of thermowell protection, thereby reducing risk of ambient thermal
damage.
Housing Temperature Rise, Above Ambient
°C (°F)
60 (108)
50 (90)
40 (72)
30 (54)
20 (36)
10 (18)
0
55
3 4
4.2
8 7 6
5
9
815°C (1500 °F) Process Temperature
540°C (1000°F) Process Temperature
250°C (482°F) Process Temperature
Extension Length (in.)