Specifications

Section 4. Sensor Support
4-24
Reference Temperature Errors Due to Panel Gradient
Chamber Changed from 85 to 25 degrees C
-6
-5
-4
-3
-2
-1
0
1
2
1 3 5 7 9 1113151719212325272931333537394143454749515355
Time Minutes
Measured - Actual degrees C
20
30
40
50
60
70
80
90
Chamber and Reference Temperatures deg. C
Channel 1
Channel 3
Channel 4
Channel 6
Channel 8
RefTemp_Avg
Chamber Temp
FIGURE 4.4-3. Panel Temperature Gradients during 80 to 25 °C Change
4.4.1.2 Thermocouple Limits of Error
The standard reference that lists thermocouple output voltage as a function of
temperature (reference junction at 0
o
C) is the NIST (National Institute of
Standards and Technology) Monograph 175 (1993). ANSI (American National
Standards Institute) has established limits of error on thermocouple wire which
is accepted as an industry standard (ANSI MC 96.1, 1975). TABLE 4.4-1
g
ives the ANSI limits of error for standard and special grade thermocouple
wire of the types accommodated by the CR1000.
TABLE 4.4-1. Limits of Error for Thermocouple Wire (Reference Junction at 0
o
C)
Limits of Error
Thermocouple Temperature (Whichever is greater)
Type Range
o
C Standard Special
T -200 to 0 ± 1.0
o
C or 1.5%
0 to 350 ± 1.0
o
C or 0.75% ± 0.5
o
C or 0.4%
J 0 to 750 ± 2.2
o
C or 0.75% ± 1.1
o
C or 0.4%
E -200 to 0 ± 1.7
o
C or 1.0%
0 to 900 ± 1.7
o
C or 0.5% ± 1.0
o
C or 0.4%
K -200 to 0 ± 2.2
o
C or 2.0%
0 to 1250 ± 2.2
o
C or 0.75% ± 1.1
o
C or 0.4%
R or S 0 to 1450 ± 1.5
o
C or 0.25% ± 0.6
o
C or 0.1%
B 800 to 1700 ± 0.5% Not Estab.