Emerson Rosemount, Reference Manual

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199
Reference Manual
00809-0100-4021, Rev GC
Appendix A: Reference Data
April 2014
Reference data
Temperature limits
Field communicator connections
Field communicator connections are permanently fixed to power/signal block.
Failure mode
The 3144P features software and hardware failure mode detection. An independent circuit
is designed to provide backup alarm output if the microprocessor hardware or software fails.
The alarm level is user-selectable using the failure mode switch. If failure occurs, the position of
the hardware switch determines the direction in which the output is driven (HIGH or LOW). The
switch feeds into the digital-to-analog (D/A) converter, which drives the proper alarm output
even if the microprocessor fails. The values at which the transmitter drives its output in failure
mode depends on whether it is configured to standard, or NAMUR-compliant (NAMUR
recommendation NE 43, 2003) operation. The values for standard and NAMUR-compliant
operation are as follows:
Load limitations
Note
HART Communication 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.
Description Operating limit Storage limit
Without LCD display –40 to 185 °F
–40 to 85 °C
–60 to 250 °F
–50 to 120 °C
With LCD display Meter –4 to 185 °F
–20 to 85 °C
–50 to 185 °F
–45 to 85 °C
Table A-2. Operation Parameters
Standard
(1)
(1) Measured in milliamperes
NAMUR-Compliant
(1)
Linear Output: 3.9

I

20.5 3.8

I

20.5
Fail HIGH: 21.75

I

23 (default) 21.5

I

23 (default)
Fail Low: I

3.75 I

3.6
Maximum Load = 40.8 X (Supply Voltage - 12.0)
(1)
(1) Without transient protection (optional).
1240
1000
750
250
0
10
12.0 Min
18.1 30 42.4
Supply Voltage (Vdc)
HART and Analog
Operating Range
4–20 mA dc
Lo
ad
(
O
h
m
s)
500
1100
Analog Only
Operating Range