Table 4-3
Type
Alpha
Beta
Delta
R-zero
PT100
0.003850
0.10863
1.49990
100Ω
D100
0.003920
0.10630
1.49710
100Ω
F100
0.003900
0.11000
1.49589
100Ω
PT385
0.003850
0.11100
1.50700
100Ω
PT3916
0.003916
0.11600
1.50594
100Ω
NTCT
0.003850
0.10863
1.49990
100Ω
Here is the temperature equation that is used to determine the RTD
temperature:
When
C
t
°
<
0
:
(
)
[
]
100
1
3
2
0
−
+
+
+
=
t
Ct
Bt
At
R
R
t
When
C
t
C
°
<
<
°
630
0
:
(
)
2
0
1
Bt
At
R
R
t
+
+
=
Where:
+
=
100
1
δ
α
A
4
10
−
⋅
−
=
α δ
B
8
10
−
⋅
−
=
α β
C
If you are using SPRTD(Standard Platinum RTD), select SPRTD and
specify the seven coefficients under SPRTD submenu.
The ITS (International Temperature Scale) -90 standard provides two
reference equations for Standard Platinum Thermometers covering
temperature range from 18.8033K to 1234.93K. However, one SPRTD
usually cannot cover the entire range, so the temperature range is
broken up into a few subranges. These subranges depend on the
calibration point of temperature scale and are based on the melting or
triple points of various pure substances. For an exact list of the
elements needed and details on RTD calibration, refer to NIST
Technical Note 1265 “Guidelines For Realizing the International
Temperature Scale of 1990”. In each subrange, the calibration
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