To test the thermister I had to heat the water and check the temp with a thermometer and check for resistance.I did this and got results of
water temp resistance
33°c 1.36kohm
35°c 1.33kohm
40°c 1.14kohm
45°c 0.96kohm
50°c 0.78kohm
55°c 0.68kohm
70°c 0.407kohm
75°c 0.390kohm
The results above shows that the higher the temp of the water the lower the resistance is in the thermister. the thermister i tested was a ntc type wich satnds for negative tempreture coefficient.This thermister is called this because the resistance decreases with increasing temperatures.Thermister is basicly just a resistor and its resistance changes with temperature.
THERMO FAN SWITCH
I put the switch in the water and set up the temp my task was to measure the resistance between the terminals at diferent temp to see wat happens with the resistance in the switch.
temperature resistance
room temperature 70.5 ohm
45°c 0.8 ohm
50°c 0.7ohm
55°c 0.9ohm
This fan switch does not meet manufacturers specifications becaus acaurding to the specifications the fan is meant to switch at 80°c but the switch that i tested switche before 40°c i know this because when it switche the tem drops to under 1°c.The thermo fan switch should not be confused with a thermistor because it is not one.The switch has two resistors inside it,it switches from one resistor to the other when the fan switches on thats y the resistance is so much diferent from when it switches on and when it of.
these results you should had graphed. Also your fan SWITCH does not look correct, it should switch open circuit at about 90 degrees, does this one meat manufactures specifications?
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