Reference Manual
00809-0100-4825, Rev BB
August 2005
Rosemount 248
1-4
Figure 1-1. Rosemount 248
Transmitter Connection Head
Temperature Rise vs. Extension
Length
Example
The transmitter specification limit is 85 °C. If the ambient temperature is 55 °C
and the process temperature to be measured is 800 °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, an extension of 100 mm meets this requirement, but 125 mm
provides a margin of 8 °C, thereby reducing any temperature effects in the
transmitter.
RETURN OF MATERIALS To expedite the return process in North America, call the Emerson Process
Management National Response Center toll-free at 800-654-7768. This
center, available 24 hours a day, will assist you with any needed information
or materials.
The center will ask for the following information:
• Product model
• Serial numbers
• The last process material to which the product was exposed
The center will provide
• A Return Material Authorization (RMA) number
• Instructions and procedures that are necessary to return goods that
were exposed to hazardous substances
NOTE
If a hazardous substance is identified, a Material Safety Data Sheet (MSDS),
required by law to be available to people exposed to specific hazardous
substances, must be included with the returned materials.
Outside North America, contact a local Emerson Process Management
representative.
60
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75
100 125 150 175 200 225
Temperature Rise Above Ambient
Extension Length (mm)
8
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