Rosemount 3244MV, Справочное руководство

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Reference Manual
00809-0100-4799, Rev BA
September 2002
A-3
Model 3244MV
Update Time
Approximately 0.5 seconds for a single sensor (1.0 second for two sensors).
Performance
The Model 3244MV with Profibus-PA maintains a specification conformance
of at least 3
.
Accuracy
Stability
±0.1% of reading or 0.1 °C, whichever is greater, for 24 months for RTDs.
±0.1% of reading or 0.1 °C, whichever is greater, for 12 months
for thermocouples.
Sensor Lead Wire Resistance Effect
RTD Input
When using a 4-wire RTD, the effect of lead resistance is eliminated and has
no impact on accuracy. However, a 3-wire sensor will not fully cancel lead
resistance error because it cannot compensate for imbalances in resistance
between the lead wires. A 2-wire sensor will produce the largest error
because it directly adds the lead wire resistance to the sensor resistance. For
2- and 3-wire RTDs, an additional lead wire resistance error is induced with
ambient temperature variations. Table A-2 and the examples shown below
help quantify these errors.
Sensor Options Input Ranges Accuracy
(1)
2-, 3-, 4-Wire RTDs °C °F °C °F
Pt 100 ( = 0.00385)
(2)
200 to 850 –328 to 1562 ± 0.10 ± 0.18
Pt 100 ( = 0.003916)
(3)
200 to 645 –328 to 1193 ± 0.10 0.18±
Pt 200
(2)
200 to 850 –328 to 1562 ± 0.22 ± 0.40
Pt 500
(2)
200 to 850 –328 to 1562 0.14 ± 0.25
Pt 1000
(2)
200 to 300 –328 to 572 ± 0.08 ± 0.14
Ni 120
(4)
200 to 300 –94 to 572 ± 0.08 ± 0.14
Cu 10
(5)
200 to 250 –58 to 482 ± 1.00 ± 1.80
Thermocouples °C °F °C °F
NIST Type B
(6) (7) (8)
212 to 3308 100 to 1820 ± 0.75 ± 1.35
NIST Type E
(5) (8)
–58 to 1832 –50 to 1000 ± 0.20 ± 0.36
NIST Type J
(6) (8)
–292 to 1400 –180 to 760 ± 0.25 ± 0.45
NIST Type K
(6) (8)
–292 to 2502 –180 to 1372 ± 0.50 ± 0.90
NIST Type N
(6) (8)
32 to 2372 0 to 1300 ± 0.40 ± 0.72
NIST Type R
(6) (8)
32 to 3214 0 to 1768 ± 0.60 ± 1.08
NIST Type S
(6) (8)
32 to 3214 0 to 1768 ± 0.50 ± 0.90
NIST Type T
(6) (8)
–328 to 752 –200 to 400 ± 0.25 ± 0.45
Millivolt Input
(9)
–10 to 100 mV ± 0.015 mV
2-, 3-, 4-Wire Ohm Input 0 to 2000 ohms ±0.35 ohm
(1) The transmitter’s accuracy is valid for the entire input range of the sensor.
(2) IEC 751;
α = 0.00385, 1995.
(3) JIS 1604, 1981.
(4) Edison Curve No. 7.
(5) Edison Copper Winding No. 15.
(6) NIST Monograph 175.
(7) Accuracy for NIST Type B T/C is ±3.0 °C (5.4 °F) from 100 to 300 °C (212 to 572°F).
(8) Total accuracy for thermocouple only: sum of ac0.25 °C (cold junction accuracy).
(9) Millivolt inputs are not approved for use with CSA option code I6.