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XDI200 Manual Version 0.1
- Page 49 -
©2017 Electromotive, Inc.
Table 5.
CLT and MAT sensor resistance
Temp,
o
C
Temp,
o
F
Resistance, ohms
-40
-40
100700
-18
0
25000
-7
19
13500
4
39
7500
20
68
3400
38
100
1800
70
158
450
100
212
185
110
230
133
120
248
102
140
284
62
5.5 Manifold Air Temperature Sensor
Like the Coolant Temperature Sensor, the Manifold Air Temperature (MAT)
Sensor is an NTC thermistor. The MAT input is used for data logging purposes.
The
XDI200
is set up to use the GM-style MAT sensors. These sensors are
sold by Electromotive under part number 305-
71220. They are threaded for a 3/8”
NPT hole. Wiring the MAT sensor is very easy. See
Figure 52
for details.
Install the MAT sensor in an area that is representative of the air temperature
entering the engine. If it is mounted directly in the intake manifold (particularly in
aluminum and iron manifolds), it may be getting a slightly warmer reading than the
actual air temperature due to the conduction of heat through the manifold and the
radiation of heat onto the sensor tip. It is sometimes better to install the sensor
upstream a bit, particularly if the air intake (or filter box) is made of a material that
does not conduct heat very well (like plastic). This will give the MAT sensor a more appropriate
reading for intake air temperature.
The MAT sensor resistance curve is identical to that of the CLT sensor. See
Figure 50
and Table 5
for details. The sensor resistance test can be done the same way as well:
70
o
F (20
o
C):
~3300
180
o
F (80
o
C):
~350
