Document
NTC thermistors for temperature measurement
Probe assemblies
Series/Type: Date:
B57514K February 2009
© EPCOS AG 2009. Reproduction, publication and dissemination of this publication, enclosures hereto and the information contained therein without EPCOS' prior express consent is prohibited.
Temperature measurement Probe assemblies
B57514K K514
Applications Temperature measurement in household appliances (e.g. dryers, cookers, small appliances)
Features NTC thermistor assembled in a stainless steel case with cable outlet Temperature range 20 to 200 °C Wire heat-resistant up to 200 °C (PTFE-insulated wire in fiberglass sleeve) Fast and simple flange installation
Options Alternative casing, cable lengths, R/T characteristics, connectors available on request.
Delivery mode Bulk
Dimensional drawing
Dimensions in mm Approx. weight 4.5 g
General technical data
Climatic category Resistance tolerance Rated temperature Dissipation factor Thermal time constant Insulation resistance Test voltage
(IEC 60068-1)
(in air) (in water) (V = 500 V DC) (t = 1 s)
Electrical specification and ordering codes
R100 Ω
3300
R25 Ω
48538
No. of R/T characteristic 7002
∆RR/RR TR δth τa Rins Vtest
20/200/42 ±2.5 100 approx. 3 approx. 3 > 100 1250
% °C mW/K s MΩ V AC
B25/100 K
3988 ±1%
Ordering code B57514K0493A001
Please read Cautions and warnings and Important notes at the end of this document.
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Temperature measurement Probe assemblies
B57514K K514
Reliability data
Test Storage in dry heat
Storage in damp heat, steady state Rapid temperature cycling
Voltage proof test
Insulation test
Standard
IEC 60068-2-2
IEC 60068-2-67
Test conditions
Storage at upper category temperature T: 200 °C t: 1000 h Temperature of air: 85 °C Relative humidity of air: 85% Duration: 1000 h Lower test temperature: 20 °C Upper test temperature: 200 °C Number of cycles: 1000 Medium: air Applied voltage between metal housing and sensor wires: 1250 V AC/60 s The sensors are placed in a vessel containing metallic balls of 1 mm diameter (with total immersed head) at room temperature. The applied voltage is 500 V DC.
∆R25/R25 (typical) < 3%
< 3%
< 3%
Remarks No visible damage
No visible damage No visible damage
No flashover
Above 100 MΩ
Please read Cautions and warnings and Important notes at the end of this document.
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Temperature measurement Probe assemblies
B57514K K514
R/T characteristics
R/T No. 7002
T (°C) 55.0 50.0 45.0 40.0 35.0
B25/100 = 3988 K
T (°C)
RT/R25
α (%/K)
96.33 66.866 47.037 33.508 24.156
7.4 65.0 7.2 70.0 6.9 75.0 6.7 80.0 6.4 85.0
B25/100 = 3988 K
T (°C)
RT/R25
α (%/K)
0.20872 0.17558 0.14837 0.12592 0.10731
3.5 185.0 3.4 190.0 3.3 195.0 3.2 200.0 3.2 205.0
B25/100 = 3988 K
RT/R25
α (%/K)
0.0086582 0.0078408 0.0071148 0.0064685 0.005892
2.0 2.0 1.9 1.9 1.8
30.0 25.0 20.0 15.0 10.0
17.613 12.98
9.6643 7.2656 5.5129
6.2
90.0 0.091816 3.1
210.0 0.0053767 1.8
6.0
95.0 0.078862 3.0
215.0 0.0049152 1.8
5.8 100.0 0.067988 2.9 220.0 0.0045011 1.7
5.6 105.0 0.058824 2.9 225.0 0.0041287 1.7
5.4 110.0 0.051071 2.8 230.0 0.0037934 1.7
5.0 0.0 5.0
10.0 15.0
4.22 3.2575 2.5348 1.9876 1.5699
5.3 115.0 0.044489 2.7 235.0 0.0034908 1.6
5.1 120.0 0.03888
2.7 240.0 0.0032173 1.6
4.9 125.0 0.034084 2.6 245.0 0.0029697 1.6
4.8 130.0 0.02997
2.5 250.0 0.0027451 1.6
4.6 135.0 0.02643
2.5 255.0 0.0025412 1.5
20.0 1.2488 25.0 1.0000 30.0 0.80594 35.0 0.65355 40.0 0.53312
4.5 4.4 4.3 4.1 4.0
140.0 145.0 150.0 155.0 160.0
0.023373 0.020727 0.018429 0.016427 0.014679
2.4 2.4 2.3 2.3 2.2
260.0 265.0 270.0 275.0 280.0
0.0023556 0.0021865 0.0020323 0.0018913 0.0017623
1.5 1.5 1.5 1.4 1.4
45.0 0.43735 50.0 0.36074 55.0 0.29911 60.0 0.24925
3.9 3.8 3.7 3.6
165.0 170.0 175.0 180.0
0.013149 0.011806 0.010623 0.0095804
2.2 2.1 2.1 2.0
285.0 290.0 295.0 300.0
0.0016441 0.0015357 0.001436 0.0013444
1.4 1.4 1.3 1.3
Please read Cautions and warnings and Important notes at the end of this document.
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Temperature measurement Probe assemblies
B57514K K514
Cautions and warnings General
See "Important notes" at the end of this document.
Storage
Store thermistors only in original packaging. Do not open the package prior to storage. Storage conditions in original packaging: storage temperature 25 °C ... +45 °C, relative humidity ≤75% annual mean, <95% maximum 30 days per annum, dew precipitation is inadmissible. Do not store thermistors where they are exposed to heat or direct sunlight. Otherwise, the packing material may be deformed or components may stick together, causing problems during mounting. Avoid contamination of thermistor surface during storage, handling and processing. Avoid storage of thermistors in harmful environments like corrosive gases (SOx, Cl etc). Use the components as soon as possible after opening the factory seals, i.e. the polyvinyl-sealed packages. Solder thermistors within the time specified after shipment from EPCOS. For leaded c.