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Trouble with creating an INC file for a thermistor

Posted: Sat Jul 22, 2017 3:57 pm
by glowryder
I've been trying to add thermistor for trans temp.

Its a Auto Meter 2259

wired to EXT_MAP Light Blue/Red In 0-5V analog input
In tuner studio I have set generic sensor 03 to read the EXT_MAP channel.

Using the below info I have tried to make an INC file (attached)

Temperature = Ohms
100°F = 1123Ω ±102Ω (Right)
120°F = 708Ω ±59Ω
140°F = 460Ω ±35Ω
150°F = 374Ω ±27Ω
170°F = 253Ω ±17Ω
190°F = 175Ω ±10Ω
200°F = 149Ω ±8Ω )
210°F = 123Ω ±7Ω
212°F = 119Ω ±6Ω
220°F = 105Ω ±5Ω
230°F = 89Ω ±5Ω
250°F = 65Ω ±4Ω
280°F = 42Ω ±3Ω
300°F = 32Ω ±2Ω
320°F = 25Ω ±2Ω
340°F = 20Ω ±1Ω

I used the wizard In TS to create the channel.
input Sensor 03
new channel name - Transmission
Transformation: INC file (selected the INC file I created that is located in the projects INC folder)


Any help would be much appreciated.

Re: Trouble with creating an INC file for a thermistor

Posted: Sat Jul 22, 2017 3:58 pm
by glowryder
Here is the INI that im guessing the wizard created.

Re: Trouble with creating an INC file for a thermistor

Posted: Sun Jul 23, 2017 6:36 am
by LT401Vette

Re: Trouble with creating an INC file for a thermistor

Posted: Sun Jul 23, 2017 11:19 am
by glowryder
Phil,

Thats what I have been referencing. Thats how I came up with my attached INC file, using format 1. When I look in TS the gauge just reads 32. I'm not sure If I :
A. did something wrong with format 1, or
I need Format B, which I don't even know where to start on how to create a format B.
or could it be the channel Im using? Im coming in on the EXT_MAP.

I figured format 1 would work since its a look up with interpolation.

Re: Trouble with creating an INC file for a thermistor

Posted: Mon Jul 24, 2017 6:31 am
by LT401Vette
It looks like your values are upside down.
TS expects the look up keys to go low to high.

Re: Trouble with creating an INC file for a thermistor

Posted: Mon Jul 24, 2017 6:38 am
by LT401Vette
Also, on the above chart you have temperatures to ohms. Is sensor03 reading RAW? That would mean it is ADC, not ohms.

An Alternate way to get the inc data you need is to use TS's Calibrate Thermoster Tables. If you put in 3 volt, Temp points and Write to controller.
TS will place a file 'std_ms2gentherm.log' in your project folder with all 1024 points it wrote to the controller.

Remember to put back your proper Thermoster Calibrations afterwards.

Re: Trouble with creating an INC file for a thermistor

Posted: Mon Jul 24, 2017 2:01 pm
by jsmcortina
Another option. If you use the 1.5.x firmware, there's a user-defined thermistor calibration curve available.

James

Re: Trouble with creating an INC file for a thermistor

Posted: Mon Jul 24, 2017 7:15 pm
by glowryder
using the custom sensor 1 seemed to get me some where! now the issue is bias resistor. Do I need to add one some where? I set it to 0, and it was way off. the higher I went (up to 5k) bias resistor setting, the more sense the temp reading made.

Looks like i need to add a 2.49K br to R65.
:R65,R66,R67 are optional 'bias' resistors on the analogue inputs EXT_MAP, EGO2, SPARE_ADC respectively.
These would be typically used when connecting a resistive temperature sensor to one of the inputs. For
standard calibration, use a 2.49K resistor with a GM style coolant or air temperature sensor

Re: Trouble with creating an INC file for a thermistor

Posted: Tue Jul 25, 2017 3:26 am
by jsmcortina
Absolutely you need a bias resistor and need to know exactly what value it is.

James