Resistance temp sender equation/formula
Posted: Mon Sep 09, 2013 2:43 am
I'm using an Autometer single wire temp sender, 5V reference from the DL-1, 1000ohm resistor and getting back very clean data, voltage ranging from 2.7 (room temp) to .5 or while hot. I've got an OBDII reader that provides deg F of the same location (the two sensors are in the same coolant passage), the DASH provides the voltage.
From teh variable manager under "create formula" portion inputted the voltages displayed in one column, actual temp in the other column, it created a formula. However, it is incorrect. Here's the values used, and the formula created:
0. * x^3 + 0.00404 * x^2 - 0.692 * x + 40.7
Deg - Volts
150 1
160 .87
170 .81
180 .71
185 .67
When the formula is used to correct the displayed value, it is no where near where it should be. Is there any other way to create a formula like this? Or is there something else within the program that I am doing wrong?
I have more data on the lower scale, starting at about 60deg F, where I need the formula though is where the voltage is down in the .45 range.
From teh variable manager under "create formula" portion inputted the voltages displayed in one column, actual temp in the other column, it created a formula. However, it is incorrect. Here's the values used, and the formula created:
0. * x^3 + 0.00404 * x^2 - 0.692 * x + 40.7
Deg - Volts
150 1
160 .87
170 .81
180 .71
185 .67
When the formula is used to correct the displayed value, it is no where near where it should be. Is there any other way to create a formula like this? Or is there something else within the program that I am doing wrong?
I have more data on the lower scale, starting at about 60deg F, where I need the formula though is where the voltage is down in the .45 range.