Page 1 of 1

Linear Temp Sensor Issue

Posted: Sun Sep 19, 2021 1:03 pm
by maniacalrick
Hello - I just received my Linear 5v temp sensor and installed it in my trans cooler line. I am using Holley Terminator X software/hardware for engine management. Local temperature readings at the sensor are about 78°F, which is ambient right now and the vehicle has been sitting, so these temps make sense. I'm seeing approximately .77 volts from the sensor, which corresponds to 48-49ish°F, which is what my Digital Dash is reading. So the system is working as installed & setup. However, the temperature readings are way off. Supply voltage is 4.99V.

I looked at the Wiki and there isn't a calibration curve for the linear temp sensor. Below is the temp to voltage scale I am running. I wanted to come here and ask questions before I tried to send the sensor back in the event its bad.

32°F = 0.50V
50°F = 0.77V
68°F = 1.03V
86°F = 1.30V
104°F = 1.57V
122°F = 1.83V
140°F = 2.10V
158°F = 2.37V
176°F = 2.63V
194°F = 2.90V
212°F = 3.17V
230°F = 3.43V
248°F = 3.70V
266°F = 3.97V
284°F = 4.23V
302°F = 4.50V

Re: Linear Temp Sensor Issue

Posted: Mon Sep 20, 2021 2:53 am
by brentp
Hi,

The sensor has a linear repsonse of 10mv/C; 0.5V at 0 degrees C

Conversion formula = (volts - 0.5) * 100

Therefore:
(.77 - .5) * 100 = 27.0
27 C = 80.6 F

Hope this helps!