1. Zero power resistance
At the specified temperature, the resistance value measured at the measurement power that causes the resistance change to be negligible relative to the total measurement error is used.
2. β value
The beta value is the thermal index of a negative temperature coefficient thermistor, which is defined as the ratio of the natural logarithmic difference of the zero power resistance at two temperatures to the difference between the reciprocals of these two temperatures.
Where: RT1 - zero power resistance at temperature T1
RT2 - zero power resistance at temperature T2
Unless otherwise specified, β values are calculated from the zero resistance values at 25°C (298.15K) and 50°C (323.15K). The β value is not a strict constant over the operating temperature range.
3.Dissipation coefficient
The ratio of the dissipation power change of the thermistor to its corresponding temperature change at the specified ambient temperature, ie:
In the operating temperature range, δ varies with the ambient temperature.
4. Thermal time constant
At zero power conditions, the temperature of the thermistor body changes by 63.2% of the difference between the two temperatures at the time when the temperature changes abruptly.
τ is proportional to the thermal capacity C of the thermistor and inversely proportional to its dissipation factor δ, ie:
5. Resistance-temperature characteristics
The relationship between the zero-power resistance value of the thermistor and the temperature of the resistor body.
6.Common sensor temperature resistance characteristics
|
|
3275K |
3380K |
3470K |
3600K |
3920K |
3950K |
4050K |
|
-30 |
52.87 |
111.3 |
63.73 |
132.4 |
33.81 |
181.7 |
|
|
-25 |
41.21 |
86.39 |
48.60 |
100.7 |
25.17 |
133.5 |
|
|
-20 |
32.44 |
67.74 |
37.40 |
77.30 |
18.90 |
98.99 |
|
|
-15 |
25.66 |
53.39 |
29.03 |
59.85 |
14.31 |
74.06 |
|
|
-10 |
20.48 |
42.45 |
22.72 |
46.70 |
10.92 |
56.06 |
288.6 |
|
-5 |
16.43 |
33.89 |
17.91 |
36.72 |
8.392 |
42.81 |
219.6 |
|
0 |
13.29 |
27.28 |
14.23 |
29.08 |
6.495 |
32.96 |
168.3 |
|
5 |
10.80 |
22.05 |
11.39 |
23.20 |
5.060 |
25.57 |
130.1 |
|
10 |
8.840 |
17.96 |
9.181 |
18.62 |
3.972 |
20.00 |
101.3 |
|
15 |
7.267 |
14.68 |
7.451 |
15.05 |
3.141 |
15.76 |
79.57 |
|
20 |
6.013 |
12.09 |
6.085 |
12.23 |
2.501 |
12.51 |
62.68 |
|
25 |
5.000 |
10.00 |
5.000 |
10.00 |
2.005 |
10.00 |
50.00 |
|
30 |
4.179 |
8.313 |
4.132 |
8.000 |
1.617 |
8.048 |
40.02 |
|
35 |
3.508 |
6.941 |
3.434 |
6.797 |
1.312 |
6.517 |
32.24 |
|
40 |
2.961 |
5.828 |
2.869 |
5.646 |
1.071 |
5.321 |
26.13 |
|
45 |
2.509 |
4.912 |
2.407 |
4.715 |
0.8789 |
4.356 |
21.30 |
|
50 |
2.137 |
4.161 |
2.032 |
3.954 |
0.7251 |
3.588 |
17.47 |
|
55 |
1.826 |
3.537 |
1.723 |
3.333 |
0.6015 |
2.972 |
14.41 |
|
60 |
1.567 |
3.021 |
1.467 |
2.821 |
0.5016 |
2.467 |
11.94 |
|
65 |
1.350 |
2.589 |
1.253 |
2.937 |
0.4025 |
2.073 |
9.954 |
|
70 |
1.168 |
2.229 |
1.073 |
2.046 |
0.3543 |
1.734 |
8.338 |
|
75 |
1.014 |
1.924 |
0.9225 |
1.752 |
0.2999 |
1.473 |
7.019 |
|
80 |
0.8835 |
1.669 |
0.7959 |
1.507 |
|
1.250 |
5.938 |
|
85 |
0.7722 |
1.451 |
0.6887 |
1.301 |
|
1.065 |
5.046 |
|
90 |
0.6771 |
1.226 |
0.5975 |
1.126 |
|
0.9110 |
4.306 |
|
95 |
0.5961 |
1.108 |
0.5196 |
0.9790 |
|
0.7824 |
3.690 |
|
100 |
0.5265 |
0.9735 |
0.4533 |
0.8535 |
|
0.6744 |
3.175 |
|
105 |
0.4654 |
0.8574 |
0.3974 |
0.7465 |
|
0.5834 |
2.742 |
|
110 |
0.4128 |
0.7579 |
0.3514 |
0.6549 |
|
0.5066 |
2.377 |
