Triumph "Fast Reacting" IAT Sensor Calibration
07-01-20, 09:24 AM
#3
Senior Member
The little bit of info I've seen is that it is a "direct replacement"
Clearly it bolts in with no mods
However, it's an assumption that "direct replacement" means the same resistance values as well.
I guess your have to get one and do a side by side test of the resistance at 3 different temperatures
Clearly it bolts in with no mods
However, it's an assumption that "direct replacement" means the same resistance values as well.
I guess your have to get one and do a side by side test of the resistance at 3 different temperatures
07-01-20, 12:22 PM
#4
full thread here:
https://www.rx7club.com/3rd-generati...sensor-882534/
https://www.rx7club.com/3rd-generati...sensor-882534/
When I first got the sensor to see if it was a suitable alternative I tested it according to the FSM. I used hot and cold water, a thermometer, and ohm meter for the test. This was the data collected.
FSM STOCK SENSOR RESISTANCE................................. FAST REACTING SENSOR
@68 *F (20c) 2.20 - 2.70 Ohms..................................Tested @68 *F (20c) = 2.27 Ohms
@176*F (80c) 0.29 - 0.35 Ohms.................................Tested @176*F (80c) = 0.34 Ohms
As you can see it's at least in line with the stock FSM resistance from 20-80*C, and I'm sure its quite close above and below that as well.
FSM STOCK SENSOR RESISTANCE................................. FAST REACTING SENSOR
@68 *F (20c) 2.20 - 2.70 Ohms..................................Tested @68 *F (20c) = 2.27 Ohms
@176*F (80c) 0.29 - 0.35 Ohms.................................Tested @176*F (80c) = 0.34 Ohms
As you can see it's at least in line with the stock FSM resistance from 20-80*C, and I'm sure its quite close above and below that as well.
Made comparison and took voltage measurements in the range 30-80 deg C. Results were excellent.
The V-ohm curves of the two sensors are very consistent, both have the same shape. Difference was systematically 1.5 C
Below is the list of all measurements taken.
Temp - C ----- V stock ----- V fast
88.2 ---------- 0.26
85.4 ---------- ---------- ---------- 0.28
84.1 ---------- 0.28
83.1 ---------- 0.29
82.6 ---------- ---------- ---------- 0.30
81.1 ---------- ---------- ---------- 0.31
80.6 ---------- 0.31
80.0 ---------- 0.32
78.9 ---------- ---------- ---------- 0.33
78.0 ---------- ---------- ---------- 0.34
77.4 ---------- 0.34
77.2 ---------- 0.35
76.6 ---------- ---------- ---------- 0.35
76.1 ---------- ---------- ---------- 0.36
75.0 ---------- 0.37
74.0 ---------- 0.38
73.8 ---------- ---------- ---------- 0.38
73.2 ---------- ---------- ---------- 0.39
72.5 ---------- 0.40
72.0 ---------- 0.41
71.5 ---------- ---------- ---------- 0.40
71.0 ---------- ---------- ---------- 0.41
70.3 ---------- 0.43
69.6 ---------- ---------- ---------- 0.43
69.0 ---------- ---------- ---------- 0.44
68.6 ---------- 0.45
68.0 ---------- 0.46
67.5 ---------- ---------- ---------- 0.46
67.0 ---------- ---------- ---------- 0.47
66.2 ---------- 0.48
65.5 ---------- 0.49
65.0 ---------- ---------- ---------- 0.49
64.5 ---------- ---------- ---------- 0.50
63.5 ---------- 0.52
63.0 ---------- ---------- ---------- 0.52
62.5 ---------- ---------- ---------- 0.53
62.0 ---------- 0.55
61.5 ---------- ---------- ---------- 0.55
61.0 ---------- 0.57
60.5 ---------- 0.58
60.0 ---------- ---------- ---------- 0.57
59.5 ---------- 0.60
69.0 ---------- ---------- ---------- 0.59
58.5 ---------- 0.62
58.0 ---------- ---------- ---------- 0.60
57.5 ---------- 0.64
57.0 ---------- ---------- ---------- 0.63
56.5 ---------- 0.65
56.0 ---------- ---------- ---------- 0.64
55.5 ---------- 0.67
55.0 ---------- ---------- ---------- 0.66
54.5 ---------- 0.70
54.0 ---------- ---------- ---------- 0.69
53.5 ---------- 0.72
53.0 ---------- ---------- ---------- 0.71
52.5 ---------- 0.75
52.0 ---------- ---------- ---------- 0.74
51.5 ---------- 0.77
51.0 ---------- ---------- ---------- 0.76
50.5 ---------- 0.80
50.0 ---------- ---------- ---------- 0.79
49.5 ---------- 0.83
49.0 ---------- ---------- ---------- 0.82
48.5 ---------- 0.86
48.0 ---------- ---------- ---------- 0.84
47.5 ---------- 0.90
47.0 ---------- ---------- ---------- 0.87
46.5 ---------- 0.93
46.0 ---------- ---------- ---------- 0.90
45.5 ---------- 0.96
45.0 ---------- ---------- ---------- 0.93
44.5 ---------- 0.99
44.0 ---------- ---------- ---------- 0.96
43.5 ---------- 1.03
43.0 ---------- ---------- ---------- 1.00
42.5 ---------- 1.07
42.0 ---------- ---------- ---------- 1.04
41.5 ---------- 1.11
41.0 ---------- ---------- ---------- 1.09
40.5 ---------- 1.16
40.0 ---------- ---------- ---------- 1.13
39.5 ---------- 1.20
39.0 ---------- ---------- ---------- 1.16
38.5 ---------- 1.24
38.0 ---------- ---------- ---------- 1.21
37.5 ---------- 1.30
37.0 ---------- ---------- ---------- 1.25
36.5 ---------- 1.35
36.0 ---------- ---------- ---------- 1.30
35.5 ---------- 1.40
35.0 ---------- ---------- ---------- 1.35
34.5 ---------- 1.46
34.0 ---------- ---------- ---------- 1.40
33.5 ---------- 1.52
33.0 ---------- ---------- ---------- 1.46
32.5 ---------- 1.59
32.0 ---------- ---------- ---------- 1.52
31.5 ---------- 1.65
31.0 ---------- ---------- ---------- 1.58
30.5 ---------- 1.71
30.0 ---------- ---------- ---------- 1.64
I also measured response time from ambient temperature to around 40 C.
Compared with the static table and stopped the clock at 90% of static voltage (actually 110% because voltage decrease as temp increases). Fast acting sensor response time was below 15 sec; OE sensor response time was above 30 sec.
- Sandro
The V-ohm curves of the two sensors are very consistent, both have the same shape. Difference was systematically 1.5 C
Below is the list of all measurements taken.
Temp - C ----- V stock ----- V fast
88.2 ---------- 0.26
85.4 ---------- ---------- ---------- 0.28
84.1 ---------- 0.28
83.1 ---------- 0.29
82.6 ---------- ---------- ---------- 0.30
81.1 ---------- ---------- ---------- 0.31
80.6 ---------- 0.31
80.0 ---------- 0.32
78.9 ---------- ---------- ---------- 0.33
78.0 ---------- ---------- ---------- 0.34
77.4 ---------- 0.34
77.2 ---------- 0.35
76.6 ---------- ---------- ---------- 0.35
76.1 ---------- ---------- ---------- 0.36
75.0 ---------- 0.37
74.0 ---------- 0.38
73.8 ---------- ---------- ---------- 0.38
73.2 ---------- ---------- ---------- 0.39
72.5 ---------- 0.40
72.0 ---------- 0.41
71.5 ---------- ---------- ---------- 0.40
71.0 ---------- ---------- ---------- 0.41
70.3 ---------- 0.43
69.6 ---------- ---------- ---------- 0.43
69.0 ---------- ---------- ---------- 0.44
68.6 ---------- 0.45
68.0 ---------- 0.46
67.5 ---------- ---------- ---------- 0.46
67.0 ---------- ---------- ---------- 0.47
66.2 ---------- 0.48
65.5 ---------- 0.49
65.0 ---------- ---------- ---------- 0.49
64.5 ---------- ---------- ---------- 0.50
63.5 ---------- 0.52
63.0 ---------- ---------- ---------- 0.52
62.5 ---------- ---------- ---------- 0.53
62.0 ---------- 0.55
61.5 ---------- ---------- ---------- 0.55
61.0 ---------- 0.57
60.5 ---------- 0.58
60.0 ---------- ---------- ---------- 0.57
59.5 ---------- 0.60
69.0 ---------- ---------- ---------- 0.59
58.5 ---------- 0.62
58.0 ---------- ---------- ---------- 0.60
57.5 ---------- 0.64
57.0 ---------- ---------- ---------- 0.63
56.5 ---------- 0.65
56.0 ---------- ---------- ---------- 0.64
55.5 ---------- 0.67
55.0 ---------- ---------- ---------- 0.66
54.5 ---------- 0.70
54.0 ---------- ---------- ---------- 0.69
53.5 ---------- 0.72
53.0 ---------- ---------- ---------- 0.71
52.5 ---------- 0.75
52.0 ---------- ---------- ---------- 0.74
51.5 ---------- 0.77
51.0 ---------- ---------- ---------- 0.76
50.5 ---------- 0.80
50.0 ---------- ---------- ---------- 0.79
49.5 ---------- 0.83
49.0 ---------- ---------- ---------- 0.82
48.5 ---------- 0.86
48.0 ---------- ---------- ---------- 0.84
47.5 ---------- 0.90
47.0 ---------- ---------- ---------- 0.87
46.5 ---------- 0.93
46.0 ---------- ---------- ---------- 0.90
45.5 ---------- 0.96
45.0 ---------- ---------- ---------- 0.93
44.5 ---------- 0.99
44.0 ---------- ---------- ---------- 0.96
43.5 ---------- 1.03
43.0 ---------- ---------- ---------- 1.00
42.5 ---------- 1.07
42.0 ---------- ---------- ---------- 1.04
41.5 ---------- 1.11
41.0 ---------- ---------- ---------- 1.09
40.5 ---------- 1.16
40.0 ---------- ---------- ---------- 1.13
39.5 ---------- 1.20
39.0 ---------- ---------- ---------- 1.16
38.5 ---------- 1.24
38.0 ---------- ---------- ---------- 1.21
37.5 ---------- 1.30
37.0 ---------- ---------- ---------- 1.25
36.5 ---------- 1.35
36.0 ---------- ---------- ---------- 1.30
35.5 ---------- 1.40
35.0 ---------- ---------- ---------- 1.35
34.5 ---------- 1.46
34.0 ---------- ---------- ---------- 1.40
33.5 ---------- 1.52
33.0 ---------- ---------- ---------- 1.46
32.5 ---------- 1.59
32.0 ---------- ---------- ---------- 1.52
31.5 ---------- 1.65
31.0 ---------- ---------- ---------- 1.58
30.5 ---------- 1.71
30.0 ---------- ---------- ---------- 1.64
I also measured response time from ambient temperature to around 40 C.
Compared with the static table and stopped the clock at 90% of static voltage (actually 110% because voltage decrease as temp increases). Fast acting sensor response time was below 15 sec; OE sensor response time was above 30 sec.
- Sandro
Last edited by neit_jnf; 07-02-20 at 09:05 AM.
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candrzej2 (07-02-20)
09-13-20, 03:55 PM
#6
^^ Thanks for posting the above. I'm kind of unclear, but it seems what the guy was actually measuring was kOhms. What I was in search of was voltage values that could be used to create a custom sensor for my Haltech Elite.
I ended up doing some testing with the Triumph sensor and thought I'd post my findings here in case anyone needs the data.
The Testing:
First I placed the IAT sensor in ambient room air and documented the resistance value using a multi meter. I used a k-type thermocoupler to (digital bbq temp probe) to measure air temps. I verified the accuracy of the thermocoupler at ambient air temp to be accurate.
Then I placed both sensors in the freezer to get a low end reading.
Next I placed both sensors into a glass jar and sealed the top with plastic wrap to create a chamber. Both sensors were suspended in air, about the same depth into the jar, and not touching the glass or each other. Placed the jar into a pot of water on the stove in order to manipulate the temp of the air inside the chamber. I started by putting ice into the water to get some cool air temp numbers.
I documented resistance values about every 10F in a range of about 32F-180F. I repeated the test 3 or 4 times to ensure the accuracy of the data. I also contrasted the resistance values seen while heating the air temp versus cooling, as these values proved to show small variations (prob due to sensor response lag). I tried to take this into consideration in my voltage map by choosing values that represented something between the heating and cooling values.
The Math:
Next I needed to translate the resistance values into voltages that the ECU can understand.
I used this equation: (5V/(pull up resistance + measured resistance))measured resistance = Sensor voltage
It's kind of hard to write algebra here, so in other words...
* Add the pull up resistor value (Haltech uses 1000Ohm pull up resistor) + the resistance measured at the sensor. This is the total resistance.
* Divide the circuit voltage by the total resistance. This is a 5V circuit so we use 5V here. This is the current running through the circuit.
* Multiply the current by the sensor resistance and you get the voltage the ECU will be seeing coming from the sensor.
I found this article to be really helpful:
https://www.hpacademy.com/previous-w...ommon-sensors/
The Data:
(deg F = Ohm = Voltage)
32.2F = 4000 = 4V
46F = 3500 = 3.89V
54F = 2750 = 3.67V
65F = 2300 = 3.48V
78F = 1950 = 3.31V
90F = 1440 = 2.95V
103F = 1070 = 2.58V
117F = 800 = 2.22V
120F = 750 = 2.14V
130F = 600 = 1.88V
140F = 500 = 1.67V
150F = 400 = 1.43V
160F = 340 = 1.27V
170F = 310 = 1.18V
178F = 270 = 1.06V
I created a custom sensor in the Elite and plugged in some voltage values from 54F-150F (I live in CA where we don't know what cold is). To my satisfaction, when viewing live sensor data after sitting all night my ETG, oil temp, water temp, and IAT all agree +/- a few degrees. I've attached my .cal file here for anyone who would find it handy.
Disclaimer: I haven't got to test this outside of just idling because my FD is the bane of my existence and not road worthy at the moment. So if you choose to use this data you should verify yourself before trusting the accuracy.
I ended up doing some testing with the Triumph sensor and thought I'd post my findings here in case anyone needs the data.
The Testing:
First I placed the IAT sensor in ambient room air and documented the resistance value using a multi meter. I used a k-type thermocoupler to (digital bbq temp probe) to measure air temps. I verified the accuracy of the thermocoupler at ambient air temp to be accurate.
Then I placed both sensors in the freezer to get a low end reading.
Next I placed both sensors into a glass jar and sealed the top with plastic wrap to create a chamber. Both sensors were suspended in air, about the same depth into the jar, and not touching the glass or each other. Placed the jar into a pot of water on the stove in order to manipulate the temp of the air inside the chamber. I started by putting ice into the water to get some cool air temp numbers.
I documented resistance values about every 10F in a range of about 32F-180F. I repeated the test 3 or 4 times to ensure the accuracy of the data. I also contrasted the resistance values seen while heating the air temp versus cooling, as these values proved to show small variations (prob due to sensor response lag). I tried to take this into consideration in my voltage map by choosing values that represented something between the heating and cooling values.
The Math:
Next I needed to translate the resistance values into voltages that the ECU can understand.
I used this equation: (5V/(pull up resistance + measured resistance))measured resistance = Sensor voltage
It's kind of hard to write algebra here, so in other words...
* Add the pull up resistor value (Haltech uses 1000Ohm pull up resistor) + the resistance measured at the sensor. This is the total resistance.
* Divide the circuit voltage by the total resistance. This is a 5V circuit so we use 5V here. This is the current running through the circuit.
* Multiply the current by the sensor resistance and you get the voltage the ECU will be seeing coming from the sensor.
I found this article to be really helpful:
https://www.hpacademy.com/previous-w...ommon-sensors/
The Data:
(deg F = Ohm = Voltage)
32.2F = 4000 = 4V
46F = 3500 = 3.89V
54F = 2750 = 3.67V
65F = 2300 = 3.48V
78F = 1950 = 3.31V
90F = 1440 = 2.95V
103F = 1070 = 2.58V
117F = 800 = 2.22V
120F = 750 = 2.14V
130F = 600 = 1.88V
140F = 500 = 1.67V
150F = 400 = 1.43V
160F = 340 = 1.27V
170F = 310 = 1.18V
178F = 270 = 1.06V
I created a custom sensor in the Elite and plugged in some voltage values from 54F-150F (I live in CA where we don't know what cold is). To my satisfaction, when viewing live sensor data after sitting all night my ETG, oil temp, water temp, and IAT all agree +/- a few degrees. I've attached my .cal file here for anyone who would find it handy.
Disclaimer: I haven't got to test this outside of just idling because my FD is the bane of my existence and not road worthy at the moment. So if you choose to use this data you should verify yourself before trusting the accuracy.
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dawggpie (09-14-20)
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