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SC-2071 Board
Chapter 3
SC-207X Series User Manual
3-18
© National Instruments Corporation
Table 3-4. NBS Polynomial Coefficients
Type
E
J
K
R
S
T
Temp.
-100
°
to 1,000
°
C
0
°
to 760
°
C
0
°
to 1,370
°
C
0
°
to 1,000
°
C
0
°
to
1,750
°
C
-160
°
to 400
°
C
Range
±
0.5
°
C
1
±
0.1
°
C
1
±
0.7
°
C
1
±
0.5
°
C
1
±
1
°
C
1
±
0.5
°
C
1
a
0
0.104967248
-0.048868252
0.226584602
0.263632917
0.927763167
0.100860910
a
1
17189.45282
19873.14503
24152.10900
179075.491
169526.5150
25727.94369
a
2
-282639.0850
-218614.5353
67233.4248
-48840341.37
-31568363.94
-767345.8295
a
3
12695339.5
11569199.78
2210340.682
1. 10
8990730663
78025595.81
a
4
-448703084.6
-264917531.4
-860963914.9
-4. 12
-1. 12
-9247486589
a
5
1. 10
2018441314
4. 10
7. 14
1. 14
6. 11
a
6
-1. 11
-1. 12
-7. 16
-1. 16
-2. 13
a
7
1. 12
1. 13
3. 18
6. 17
3. 14
a
8
-9. 12
-6. 13
-8. 19
-1. 19
a
9
2. 13
1. 20
1
The accuracies shown apply only to the polynomial and do not take into consideration errors introduced by
the SC-2071 board, the Lab/1200 device, or the thermocouple itself.
These polynomials are accurate only within the temperature ranges specified. Also, all terms
must be included to achieve the specified accuracy.
To avoid the long computation time required for these high-order polynomials, you can
subdivide the operating range of a thermocouple into several smaller ranges. Each of the smaller
ranges can then be approximated by a much lower order polynomial, such as the polynomial in
Formula 3-6. Further examples of polynomials, including lower-order polynomials for
subdivided temperature ranges, can be found in NIST Monograph 175, Temperature-
Electromotive Force Reference Functions and Tables for the Letter-Designated Thermocouple
Types Based on the ITS-90 (National Institute of Standards and Technology, Gaithersburg, MD
20899).
Measurement Connections
Connect the temperature sensor to channel 0 by configuring jumper W1 as shown in Figure 3-3.
Connect the positive leads of the thermocouples to any SC-2071 board input channels except
CH0. Connect the negative leads to AIGND. Notice that some thermocouples, such as those
from Omega Engineering (Stamford, CT), have red insulation on the negative terminal. Check
with the vendor to determine the output polarity of any particular thermocouple. For more
information about signal sources and their connections, see Chapter 2 in your Lab/1200 device
user manual.
Summary of Contents for SC-207 Series
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