Temperature Limits; Hardware And Software Failure Mode; Custom Alarm And Saturation Level; Turn-On Time - Emerson Rosemount 644 HART Reference Manual

Reference Manual
00809-0100-4728, Rev MB
A.2.3 Temperature limits
Operating limit Storage limit
–4 to 185 °F
With LCD Display
–20 to 85 °C
–40 to 185 °F
Without LCD Display
–40 to 85 °C
A.2.4 Hardware and software failure mode
The Rosemount 644 features software driven alarm diagnostics.
The independent circuit is designed to provide backup alarm
output if the microprocessor software fails. The alarm directions
(HIGH/LO) are user-selectable using the failure mode switch. If
failure occurs, the position of the switch determines the direction
in which the output is driven (HI or LO). 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, custom, or NAMUR-compliant (NAMUR
recommendation NE 43, June 1997) operation.
the alarm ranges available for the device to be configured to.
A.2.8 Accuracy
Table A-2. Rosemount 644 Input Options and Accuracy
Sensor
options
2-, 3-, 4-wire RTDs
Pt 100 ( = 0.00385)
Pt 200 ( = 0.00385)
Pt 500 ( = 0.00385)
Pt 1000 ( = 0.00385)
Pt 100 ( = 0.003916)
Pt 200 ( = 0.003916)
Ni 120 Edison Curve No. 7
Cu 10
Winding No. 15
Pt 50 ( = 0.00391)
Pt 100 ( = 0.00391)
Cu 50 ( = 0.00426)
Cu 50 ( = 0.00428)
Cu 100 ( = 0.00426)
Cu 100 ( = 0.00428)
(4)
Thermocouples
NIST Monograph
(5)
Type B
NIST Monograph
Type E
86
–50 to 185 °F
–45 to 85 °C
–58 to 248 °F
–50 to 120 °C
Table A-1
Sensor
reference
°C
IEC 751 –200 to 850
IEC 751 –200 to 850
IEC 751 –200 to 850
IEC 751 –200 to 300
JIS 1604 –200 to 645
JIS 1604 –200 to 645
–70 to 300
Edison Copper
–50 to 250
GOST 6651-94 –200 to 550
GOST 6651-94 –200 to 550
GOST 6651-94 –50 to 200
GOST 6651-94 –185 to 200
GOST 6651-94 –50 to 200
GOST 6651-94 –185 to 200
100 to 1820
175, IEC 584
–50 to 1000
175, IEC 584
Table A-1. Available Alarm Range
Linear Output: 3.9  I
Fail High:
Fail Low:
1. Measured in milliamperes.
2. I = Process Variable (current output).
A.2.5 Custom alarm and saturation level
Custom factory configuration of alarm and saturation level is
available with option code C1 for valid values. These values can
also be configured in the field using a Field Communicator.
A.2.6 Turn-on time
Performance within specifications in less than 5.0 seconds after
power is applied, when damping value is set to 0 seconds.
shows
A.2.7 Transient protection
The Rosemount 470 prevents damage from transients induced by
lightning, welding, or heavy electrical equipment. For more
information, refer to the Rosemount 470 Product Data Sheet
(document number 00813-0100-4191).
Input Recommended
ranges Min. Span
°F °C
–328 to 1562 10
–328 to 1562 10
–328 to 1562 10
–328 to 572 10
–328 to 1193 10
–328 to 1193 10
–94 to 572 10
–58 to 482 10
–328 to 1022 10
–328 to 1022 10
–58 to 392 10
–301 to 392 10
–58 to 392 10
–301 to 392 10
212 to 3308 25
–58 to 1832 25
Specifications and Reference Data
(1)
NAMUR- NE 43
Standard
Compliant
 20.5 3.8  I  20.5
(2)
21  I  23 21  I  23
3.5  I  3.75 3.5  I  3.6
Digital
(1) (2)

accuracy

°F °C °F
18 ± 0.15 ± 0.27
18 ± 0.15 ± 0.27
18 ± 0.19 ± 0.34
18 ± 0.19 ± 0.34
18 ± 0.15 ± 0.27
18 ± 0.27 ± 0.49
18 ± 0.15 ± 0.27
18 ±1.40 ± 2.52
18 ± 0.30 ± 0.54
18 ± 0.15 ± 0.27
18 ±1.34 ± 2.41
18 ±1.34 ± 2.41
18 ±0.67 ± 1.20
18 ±0.67 ± 1.20
45 ± 0.77 ± 1.39
45 ± 0.20 ± 0.36
Specifications and Reference Data
July 2016
D/A
(3)
accuracy
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span
±0.03% of span