*
H3
Rev. 10/16/12
29
31
33
35
23
25
27
15
17
19
21
5
7
9
11
13
-5
-3
-1
1
3
°F °C
-39 -39.44
-27
-25
-23
-21
-19
-17
-15
-13
-37
-35
-33
-31
-29
-11
-9
-7
-38.33
-37.22
-36.11
-35.00
-33.89
-32.78
-31.67
-30.56
-29.44
-28.33
-27.22
-26.11
-25.00
-23.89
-22.78
-21.67
-20.56
-19.44
-18.33
-17.22
-16.11
-5.00
-3.89
-2.78
-1.67
-0.56
0.56
1.67
-15.00
-13.89
-12.78
-11.67
-10.56
-9.44
-8.33
-7.22
-6.11
12791
12106
11468
10868
10303
6159
5861
5580
5314
5062
4822
4596
9771
9270
8798
8352
7933
7533
7159
6807
6473
Ohms
34389
32336
30419
28628
26955
25390
23927
22557
21275
20064
18939
17885
16896
15969
15098
14281
13512
°F °C Ohms
37 2.78
4383
91
93
95
83
85
87
89
73
75
77
79
81
67
69
71
97
99
101
103
105
107
109
111
59
61
63
65
53
55
57
45
47
49
51
39
41
43
28.33
29.44
30.56
31.67
32.78
33.89
35.00
19.44
20.56
21.67
22.78
23.89
25.00
26.11
27.22
36.11
37.22
38.33
39.44
40.56
41.67
42.78
43.89
11.67
12.78
13.89
15.00
16.11
17.22
18.33
3.89
5.00
6.11
7.22
8.33
9.44
10.56
1590
1527
1466
1408
1353
1300
1250
2225
2131
2042
1957
1877
1800
1727
1657
1201
1155
1111
1069
1029
990
954
918
3028
2895
2769
2649
2535
2426
2323
4180
3989
3807
3635
3471
3316
3167
°F °C Ohms
113 45.00
885
115 46.11
852
163
165
167
169
171
173
175
149
151
153
155
157
159
161
177
179
181
183
185
187
135
137
139
141
143
145
147
117
119
121
123
125
127
129
131
133
72.78
73.89
75.00
76.11
77.22
78.33
79.44
65.00
66.11
67.22
68.33
69.44
70.56
71.67
57.22
58.33
59.44
60.56
61.67
62.78
63.89
47.22
48.33
49.44
50.56
51.67
52.78
53.89
55.00
56.11
80.56
81.67
82.78
83.89
85.00
86.11
372
360
349
338
327
317
307
468
452
438
423
410
396
384
298
289
280
272
264
256
595
574
555
536
518
500
484
822
792
763
736
710
685
661
638
616
* All Passive Thermistors 10K Ω and smaller are CE compliant.
Building Automation Products, Inc. • 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel: +1-608-735-4800 • Fax: +1-608-735-4804 • Email: sales@bapihvac.com • Web: www.bapihvac.com

H2
*
Rev. 01/06/14
BAPI Thermistors are thermally sensitive resistors known for exhibiting a large change in resistance with only a small change in temperature.
It is important to note that a thermistor’s change in resistance is non-linear. It follows a pre-defined curve which is provided by the thermistor manufacturer. An example of a thermistor output curve can be seen in Figure 1 .
Thermistors are manufactured to follow a specific curve with a high degree of accuracy. All BAPI thermistors have a standard accuracy of ± 0.2 °C throughout the commercial temperature range of
0 to 70 °C. BAPI also has available a higher accuracy sensor for meeting tougher specs. The extra precision [XP] line has an initial accuracy of ± 0.1 °C throughout the commercial temperature range of 0 to 70 °C. Please call for availability and pricing on [XP] line thermistors. Both accuracy levels allow BAPI thermistors to be interchanged without the extra expense of offsetting the controller.
* All Passive Thermistors 10K Ω and smaller are CE compliant.
DEFINITION OF SPECIFICATION TERMS
Interchangeability Tolerance (Accuracy):
The maximum amount that thermistors following the same curve will differ from each other.
Dissipation Constant:
The power needed to raise the thermistor’s body temperature by 1°C. At the heart of all
BAPI thermistor products is a sensor with a 2.7 mW/°C dissipation constant to ensure that selfheating stays at an absolute minimum.
Stability (drift):
The amount that the resistance characteristics of a thermistor will change. BAPI uses only the highest quality, “pre-aged” thermistors with very small drift values. Over a ten year span, BAPI thermistors will not change more than 0.1°C.
Operating Range:
The operating range shown is for the thermistor only. The mounting package may further limit the operating range and is described on each mounting type specification. The thermal time constant will also be affected based on the added mass of the stainless steel probe and moisture protection encapsulation.
Thermal Time Constant
Bare sensors are typically measured and specified in still air and are timed at the statistical 63.2% of the step temperature change. A stirred liquid test will typically result in a much faster response time and is also timed at 63.2% of the step temperature change. The time constant is always the same whatever the temperature step change may be.
Interchangeability Tolerance (Accuracy):
Standard Sensor: ± 0.2 °C (0 to 70 °C)
Wide Range Standard: ± 0.4 °C (-55 to 150 °C)
High Accuracy [XP] Sensor: ± 0.1 °C (0 to 70 °C)
Wide Range High Accuracy: ± 0.2 °C (-55 to 150 °C)
Dissipation Constant: 2.7 mW/°C
Stability (drift): Less than 0.02 °C / year
The r mal Time Constant: 5 seconds (bead in still air)
.5 seconds (stirred liquid)
Sensor
Type
1.8K
2.2K
3K**
3.3K
10K-2**
10K-3**
20K**
47K
50K
100K**
Reference
Resistance
1.8 K Ω @ 25 °C
2.2 K Ω @ 25 °C
3 K Ω @ 25 °C
3.3 K Ω @ 25 °C
10 K Ω @ 25 °C
10 K Ω @ 25 °C
10K-3(11K)** 5.2 K Ω @ 25 °C
20 K Ω @ 25 °C
47 K Ω @ 25 °C
50 K Ω @ 25 °C
Operating
Range
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-55 to 150 °C
-80 to 150 °C
100 K Ω @ 25 °C -55 to 150 °C
Other Thermistors are available. Contact BAPI for availability and specifications of additional thermistors.
**Available as an [XP] high accuracy sensor.
Minimum quantities and long lead times may apply.
10K-2[XP] and 10K-3[XP] thermistors are typically stocked items
Building Automation Products, Inc. • 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel: +1-608-735-4800 • Fax: +1-608-735-4804 • Email: sales@bapihvac.com • Web: www.bapihvac.com