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National Instruments Corporation
11
SCXI-1327 Installation Guide
Electromagnetic Compatibility
EMC/EMI............................................... CE, C-Tick, and FCC Part 15
(Class A) Compliant
Electrical emissions................................ EN 55011 Class A at 10 m
FCC Part 15A above 1 GHz
Electrical immunity................................ Evaluated to EN 61326:1998,
Table 1
Note
This device should only be operated with shielded cabling for full EMC and EMI
compliance. See the
Declaration of Conformity
for this product for any additional
regulatory compliance information.
Temperature Sensor Output and Accuracy
The SCXI-1327 temperature sensor outputs 1.91 to 0.65 V from 0 to 50 °C.
Converting a Thermistor Voltage to a Temperature
National Instruments software can convert a thermistor voltage to
the thermistor temperature for the circuit diagram shown in Figure 3.
In LabVIEW, you can use the Convert Thermistor Reading VI that is found
in the
Data Acquisition»Signal Conditioning
palette. If you are using
CVI or NI-DAQ, use the
Thermistor_Convert
function. The VI takes
the output voltage of the temperature sensor, the reference voltage, and the
precision resistance and returns the thermistor temperature.
Alternatively, you can use the following formulas:
where
T
K
is the temperature in Kelvin
a
= 1.295361
×
10
–
3
b
= 2.343159
×
10
–
4
c
= 1.018703
×
10
–
7
R
T
= resistance of the thermistor in ohms
T
°
C
( )
T
K
273.15
–
=
T
K
1
a
b
R
T
ln
(
)
c
R
T
ln
(
)
3
+
+
[
]
----------------------------------------------------------------
=
R
T
5 000
V
TEMPOUT
2.5
V
TEMPOUT
–
--------------------------------------
,
=
Содержание SCXI-1327
Страница 15: ......
