Emerson Rosemount 248, Справочное руководство

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Reference Manual
00809-0100-4825, Rev CB
Appendix A: Specifications and reference data
March 2014
51
Specifications and Reference Data
Appendix A Specifications and reference
data
Transmitter specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 51
Sensor specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 57
Dimensional drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 60
Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 62
A.1 Transmitter specifications
A.1.1 Functional specifications
Inputs
User-selectable. See
“Transmitter accuracy and ambient temperature effects” on page 55
for sensor
options.
Output
2-wire 4–20 mA, linear with temperature or input; digital output signal superimposed on 4–
20 mA signal, available for a Field communicator or control system interface
Isolation
Input/output isolation tested to 500 Vac rms (707 Vdc) at 50/60 Hz
Power supply
An external power supply is required. The transmitter operates on 12.0 to 42.4 Vdc transmitter
terminal voltage with load resistance between 250 and 1100 ohms. A minimum of 17.75 Vdc
power supply is required with a load of 250 ohms. Transmitter power terminals are rated to
42.4 Vdc. A Field Communicator requires a loop resistance between 250 and 1100 ohms. Do
not communicate with the transmitter when power is below 12 Vdc at the transmitter
terminals.
Humidity limits
0–99% relative humidity, non-condensing
NAMUR recommendations
The Rosemount 248 meets the following NAMUR recommendations:

NE 21 – Electromagnetic compatibility (EMC) for Process and Laboratory Apparatus

NE 43 – Standard of the signal level breakdown information of digital transmitters

NE 89 – Standard of temperature transmitters with digital signal processing