Chapter 2
Configuration and Installation
2-30
ni.com
where
V
TEMPOUT
is the temperature sensor output and T (°F) and T (°C) are
the temperature readings in degrees Fahrenheit and degrees Celsius,
respectively.
The SCXI-1328 temperature sensor outputs 0.62 to 0.07 V from 0 to 55 °C
and has an accuracy of ±0.35 °C over the 15 to 35 °C range and ±0.65 °C
over the 0 to 15 °C and 35 to 55 °C ranges. To determine the temperature,
use the following formulas:
where T
K
is the temperature in kelvin
a
= 1.288
×
10
–3
b
= 2.356
×
10
–4
c
= 9.556
×
10
–8
R
T
= resistance of the thermistor in
Ω
V
TEMPOUT
= output voltage of the temperature sensor
where T (°F) and T (°C) are the temperature readings in degrees Fahrenheit
and degrees Celsius, respectively.
Terminal Block Jumper Configuration
In addition to the screw terminals, the terminal block has one jumper for
configuring the onboard temperature sensor. When you set jumper W1 on
the SCXI-1320 or SCXI-1328 (jumper W5 on the SCXI-1321) to the
MTEMP position, the jumper connects the temperature sensor output to the
T
°
F
( )
T
°
C
( )
[
]
9
5
-----------------------
32
+
=
T
°
C
( )
T
K
273.15
–
=
T
K
1
a b
R
T
ln
(
)
c
R
T
ln
(
)
3
+
+
[
]
--------------------------------------------------------------
=
R
T
50,000
V
TEMPOUT
2.5
V
TEMPOUT
–
--------------------------------------
=
T
°
F
( )
T
°
C
( )
[
]
9
5
-----------------------
32
+
=