Fenwal 10k thermistors, curve 16
New "lookup table" spreadsheet for LibraOffice or Zipped Version for download issues. Type in resistance - get temperature.

The lookup function should be easy to examine and understand for making more sophisticated spreadsheets. My plan is to build a PicAXE ohmmeter that will send data to this spreadsheet for conversion and plotting, probably using the ratiometric V/F for conversion.


Also: (Here's a .pdf with 0.1 degree steps and Fahrenheit conversion. Here's a spreadsheet to make building a lookup table a bit easier.) These values were calculated by me using the Steinhart-Hart equation over several smaller temperature ranges on the theory that would yield a better result. But it's been decades since I did it, so I hope it's accurate and I can't defend it, either! These values do compare well against published values. The values in between integer degrees are calculated by linear interpolation. Grab a 0.1 degree "interchangeable" thermistor and you have a pretty spectacular temperature reference for the experimenter's lab. The chart goes to 100C but I'd recommend not heating such a good thermistor above 70C to prevent temperature-induced drift.

-50    670,100
-49    623,682
-48    580,809
-47    541,260
-46    504,665
-45    470,830
-44    439,540
-43    410,529
-42    383,656
-41    358,723
-40    335,615
-39    314,145
-38    294,195
-37    275,646
-36    258,390
-35    242,329
-34    227,358
-33    213,433
-32    200,440
-31    188,315
-30    176,998
-29    166,434
-28    156,562
-27    147,337
-26    138,704
-25    130,630

-25    130,630
-24    123,070
-23    115,991
-22    109,358
-21    103,141
-20    97,313
-19    91,839
-18    86,705
-17    81,888
-16    77,355
-15    73,100
-14    69,098
-13    65,337
-12    61,797
-11    58,466
-10    55,330
-9      52,391
-8      49,626
-7      47,026
-6      44,581
-5      42,280
-4      40,110
-3      38,068
-2      36,142
-1      34,327
0       32,613

0      32,613
1      30,996
2      29,469
3      28,026
4      26,664
5      25,375
6      24,157
7      23,004
8      21,912
9      20,879
10    19,900
11    18,973
12    18,094
13    17,259
14    16,469
15    15,719
16    15,007
17    14,331
18    13,689
19    13,079
20    12,500
21    11,948
22    11,425
23    10,926
24    10,451
25    10,000

25    10,000
26    9,570.7
27    9,162.8
28    8,774.4
29    8,404.9
30    8,053.3
31    7,718.4
32    7,399.4
33    7,095.4
34    6,805.8
35    6,529.5
36    6,266.0
37    6,014.4
38    5,774.7
39    5,545.7
40    5,327.2
41    5,118.1
42    4,918.5
43    4,727.7
44    4,545.3
45    4,370.9
46    4,204.0
47    4,044.5
48    3,891.7
49    3,745.4
50    3,605.3

50    3,605.3
51    3,471.1
52    3,342.7
53    3,219.5
54    3,101.4
55    2,988.3
56    2,879.8
57    2,775.7
58    2,675.8
59    2,580.0
60    2,488.0
61    2,400.1
62    2,315.8
63    2,234.89
64    2,157.32
65    2,082.82
66    2,011.31
67    1,942.66
68    1,876.72
69    1,813.37
70    1,752.49
71    1,693.98
72    1,637.72
73    1,583.62
74    1,531.59
75    1,481.52

75    1,481.52
76    1,433.36
77    1,387.00
78    1,342.39
79    1,299.39
80    1,258.00
81    1,218.16
82    1,179.72
83    1,142.70
84    1,107.03
85    1,072.64
86    1,039.47
87    1,007.49
88    976.630
89    946.900
90    918.150
91    890.430
92    863.670
93    837.830
94    812.860
95    788.790
96    765.520
97    743.030
98    721.300
99    700.300
100   680.000

Surplus Thermistors:

-40     100,707
-35     72,458
-30     52,684
-25     38,688
-20     28,677
-15     21,488
-10     16,176
-5       12,300
0         9,423
5         7,282
10       5,672
15       4,450
20       3,515
25       2,796
30       2,238
35      1,802
40      1,459
45      1,188
50      973
55      804
60      667
65      557
70      467
75      393
80      332
85      282
0        241
95      206
100    177
105    152
110    132
115    115
120    99.9
121    97.2
122    94.6
123    92.1
124    89.7
125    87.4
126    85.1
127    82.9
128    80.8
129    78.7
130    76.8
140    59.8
150    47.2

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