EPCOS B57276K0123A024

NTC thermistors for
temperature measurement
Probe assemblies
Series/Type:
B57276K
Date:
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
B57276K
Probe assemblies
K276
Applications
Washing machines
Dish washers
Tumble-dryers
Water boilers
Features
Suitable for use in corrosive environments
Compact stainless steel case
RAST 2.5 or RAST 5 connector
Cost-effective ready-to-use sensor
UL approval (E69802)
VDE approval (DIN EN 60539-1: 2002)
Options
Alternative resistance ratings, rated temperatures and resistance tolerances
available on request.
RAST 5 plug terminals or RAST 2.5 connector with bar available on request.
Type Z276 and Z278 with different geometry and faster response time available on request.
Delivery mode
Bulk
Dimensional drawings
Dimensions
R60
Ω
A max. Plug terminal
mm
mm
RAST 2.5 connector
1204
∅ 14.5
3243
∅ 12.4
RAST 5 connector
1082
∅ 14.5
3243
∅ 12.4
Approx. weight 9 g
Approx. weight 9 g
Please read Cautions and warnings and
Important notes at the end of this document.
Page 2 of 11
6.3 x 0.8
4.8 x 0.8
Temperature measurement
B57276K
Probe assemblies
K276
General technical data
Climatic category
Max. power
Resistance tolerance
Dissipation factor
Thermal time constant
Heat capacity
Insulation resistance
Test voltage
(IEC 60068-1)
(at 25 °C)
(in water)
(in water)
(V = 100 V DC)
(t = 1 s)
P25
∆RR/RR
δth
τa
Cth
Rins
Vtest
10/100/56
500
±2
approx. 20
approx. 20
approx. 500
> 1000
3750
mW
%
mW/K
s
mJ/K
MΩ
V AC
Electrical specification and ordering codes
TR
°C
RR
Ω
RAST 2.5 connector
60
1204
60
3243
RAST 5 connector
63
1082
60
3243
R25
Ω
No. of R/T
B25/100
characteristic K
4829
11981
2003
2901
3980 ±1%
3760 ±1.5%
B57276K0482A007
B57276K0123A028
4829
11981
2003
2901
3980 ±1.5%
3760 ±1.5%
B57276K0482A009
B57276K0123A024
Please read Cautions and warnings and
Important notes at the end of this document.
Page 3 of 11
Ordering code
Temperature measurement
B57276K
Probe assemblies
K276
Reliability data
Test
Standard
Storage in
dry heat
IEC
60068-2-2
Storage in damp
heat, steady state
Rapid temperature
cycling
Endurance
Long-term stability
(empirical value)
Robustness of
terminations
Test conditions
Storage at upper
category temperature
T: 100 °C
t: 1000 h
IEC
Temperature of air: 40 °C
60068-2-78 Relative humidity of air: 93%
Duration: 56 days
IEC
Lower test temperature: 10 °C
60068-2-14 Upper test temperature: 100 °C
Number of cycles: 10
Pmax: 500 mW
t: 1000 h
Temperature: 100 °C
t: 10000 h
DIN
Pull-out force
46 249
(both connectors together)
F = 50 N
Please read Cautions and warnings and
Important notes at the end of this document.
Page 4 of 11
∆R25/R25
(typical)
< 2%
Remarks
< 1%
No visible
damage
< 1%
No visible
damage
< 2%
No visible
damage
No visible
damage
No visible
damage
< 3%
No visible
damage
Temperature measurement
B57276K
Probe assemblies
K276
R/T characteristics
R/T No.
T (°C)
2003
2901
B25/100 = 3980 K
B25/100 = 3760 K
RT/R25
α (%/K) RT/R25
α (%/K)
55.0
50.0
45.0
40.0
35.0
97.578
67.65
47.538
33.831
24.359
7.5
7.2
7.0
6.7
6.5
63.969
46.179
33.738
24.927
18.611
6.7
6.4
6.2
6.0
5.8
30.0
25.0
20.0
15.0
10.0
17.753
13.067
9.7228
7.3006
5.5361
6.3
6.0
5.8
5.6
5.5
14.033
10.679
8.198
6.3123
4.9014
5.6
5.4
5.3
5.2
5.1
5.0
0.0
5.0
10.0
15.0
4.2332
3.266
2.5392
1.9902
1.5709
5.3
5.1
5.0
4.8
4.7
3.821
3.0027
2.3801
1.9
1.5257
4.9
4.7
4.6
4.5
4.3
20.0
25.0
30.0
35.0
40.0
1.2492
1.0000
0.80575
0.65326
0.5329
4.5
4.4
4.3
4.1
4.0
1.233
1.0000
0.81679
0.67166
0.55527
4.3
4.1
4.0
3.9
3.8
45.0
50.0
55.0
60.0
65.0
0.43715
0.36064
0.29908
0.24932
0.20886
3.9
3.8
3.7
3.6
3.5
0.46095
0.38459
0.32184
0.27068
0.22907
3.8
3.7
3.6
3.5
3.3
70.0
75.0
80.0
85.0
90.0
0.17578
0.14863
0.12621
0.10763
0.092159
3.4
3.3
3.2
3.1
3.1
0.19468
0.16607
0.14221
0.12218
0.10533
3.2
3.1
3.1
3.0
2.9
95.0
100.0
105.0
110.0
115.0
0.079225
0.068356
0.059247
0.051531
0.044921
3.0
2.9
2.8
2.8
2.7
0.09123
0.079284
0.069062
0.06034
0.052886
2.8
2.8
2.7
2.7
2.6
120.0
125.0
130.0
135.0
140.0
0.039282
0.034387
0.030186
0.02665
0.023594
2.7
2.6
2.5
2.5
2.4
0.046482
0.040985
0.036233
0.032101
0.02851
2.5
2.5
2.5
2.4
2.4
145.0
150.0
155.0
0.020931
0.018616
0.016612
2.4
2.3
2.3
0.025373
0.022633
0.020231
2.3
2.3
2.3
Please read Cautions and warnings and
Important notes at the end of this document.
Page 5 of 11
Temperature measurement
B57276K
Probe assemblies
Please read Cautions and warnings and
Important notes at the end of this document.
K276
Page 6 of 11
Temperature measurement
B57276K
Probe assemblies
K276
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 components this is 24 months, for SMDs 12 months.
Handling
NTC thermistors must not be dropped. Chip-offs or any other damage must not be caused
during handling of NTCs.
Do not touch components with bare hands. Gloves are recommended.
Avoid contamination of thermistor surface during handling.
Bending / twisting leads
A lead (wire) may be bent at a minimum distance of twice the wire’s diameter plus 4 mm from
the component head or housing. When bending ensure the wire is mechanically relieved at the
component head or housing. The bending radius should be at least 0.75 mm.
Twisting (torsion) by 180° of a lead bent by 90° is permissible at 6 mm from the bottom of the
thermistor body.
Soldering
Use resin-type flux or non-activated flux.
Insufficient preheating may cause ceramic cracks.
Rapid cooling by dipping in solvent is not recommended.
Complete removal of flux is recommended.
Please read Cautions and warnings and
Important notes at the end of this document.
Page 7 of 11
Temperature measurement
B57276K
Probe assemblies
K276
Mounting
Ensure that no thermo-mechanical stress occurs due to production processes (curing or
overmolding processes) when thermistors are sealed, potted or overmolded or during their
subsequent operation. The maximum temperature of the thermistor must not be exceeded.
Ensure that the materials used (sealing/potting compound and plastic material) are chemically
neutral.
Electrodes/contacts must not be scratched or damaged before/during/after the mounting
process.
Contacts and housing used for assembly with the thermistor must be clean before mounting.
Ensure that adjacent materials are designed for operation at temperatures comparable to the
surface temperature of the thermistor. Be sure that surrounding parts and materials can
withstand the temperature.
Avoid contamination of the thermistor surface during processing.
The connections of sensors (e.g. cable end, wire end, plug terminal) may only be exposed to
an environment with normal atmospheric conditions.
Tensile forces on cables or leads must be avoided during mounting and operation.
Bending or twisting of cables or leads directly on the thermistor body is not permissible.
Avoid using chemical substances as mounting aids. It must be ensured that no water or other
liquids enter the NTC thermistors (e.g. through plug terminals). In particular, water based
substances (e.g. soap suds) must not be used as mounting aids for sensors.
Operation
Use thermistors only within the specified operating temperature range.
Use thermistors only within the specified power range.
Environmental conditions must not harm the thermistors. Only use the thermistors under
normal atmospheric conditions or within the specified conditions.
Contact of NTC thermistors with any liquids and solvents should be prevented. It must be
ensured that no water enters the NTC thermistors (e.g. through plug terminals). For
measurement purposes (checking the specified resistance vs. temperature), the component
must not be immersed in water but in suitable liquids (e.g. Galden).
Avoid dewing and condensation unless thermistor is specified for these conditions.
Bending or twisting of cables and/or wires is not permissible during operation of the sensor in
the application.
Be sure to provide an appropriate fail-safe function to prevent secondary product damage
caused by malfunction.
This listing does not claim to be complete, but merely reflects the experience of EPCOS AG.
Please read Cautions and warnings and
Important notes at the end of this document.
Page 8 of 11
Temperature measurement
B57276K
Probe assemblies
K276
Symbols and terms
Symbol
English
German
A
AWG
Area
American Wire Gauge
Fläche
Amerikanische Norm für Drahtquerschnitte
B
B25/100
B value
B value determined by resistance
measurement at 25 °C and 100 °C
B-Wert
B-Wert, ermittelt durch Widerstandsmessungen bei 25 °C und 100 °C
Cth
Heat capacitance
Wärmekapazität
I
Current
Strom
N
Number (integer)
Anzahl (ganzzahliger Wert)
P25
Pdiss
Pel
Pmax
Maximum power at 25 °C
Power dissipation
Electrical power
Maximum power within stated
temperature range
Maximale Leistung bei 25 °C
Verlustleistung
Elektrische Leistung
Maximale Leistung im
angegebenenTemperaturbereich
∆RB/RB
Resistance tolerance caused by
spread of B value
Insulation resistance
Parallel resistance
Rated resistance
Resistance tolerance
Series resistance
Resistance at temperature T
(e.g. R25 = resistance at 25 °C)
Widerstandstoleranz, die durch die
Streuung des B-Wertes verursacht wird
Isolationswiderstand
Parallelwiderstand
Nennwiderstand
Widerstandstoleranz
Serienwiderstand
Widerstand bei Temperatur T
(z.B. R25 = Widerstand bei 25 °C)
T
∆T
t
TA
Tmax
Temperature
Temperature tolerance
Time
Ambient temperature
Upper category temperature
Tmin
Lower category temperature
Temperatur
Temperaturtoleranz
Zeit
Umgebungstemperatur
Obere Grenztemperatur
(Kategorietemperatur)
Untere Grenztemperatur
(Kategorietemperatur)
Top
TR
Tsurf
Operating temperature
Rated temperature
Surface temperature
Betriebstemperatur
Nenntemperatur
Oberflächentemperatur
V
Vins
Vop
Vtest
Voltage
Insulation test voltage
Operating voltage
Test voltage
Spannung
Isolationsprüfspannung
Betriebsspannung
Prüfspannung
Rins
RP
RR
∆RR/RR
RS
RT
Please read Cautions and warnings and
Important notes at the end of this document.
Page 9 of 11
Temperature measurement
B57276K
Probe assemblies
K276
Symbol
English
German
α
Temperature coefficient
Temperaturkoeffizient
∆
Tolerance, change
Toleranz, Änderung
δth
Dissipation factor
Wärmeleitwert
τc
τa
Thermal cooling time constant
Thermal time constant
Thermische Abkühlzeitkonstante
Thermische Zeitkonstante
Abbreviations / Notes
Symbol
English
German
Surface-mounted devices
Oberflächenmontierbares Bauelement
*
To be replaced by a number in ordering Platzhalter für Zahl im Bestellnummerncodes, type designations etc.
code oder für die Typenbezeichnung.
+
To be replaced by a letter.
Platzhalter für einen Buchstaben.
All dimensions are given in mm.
Alle Maße sind in mm angegeben.
The commas used in numerical values
denote decimal points.
Verwendete Kommas in Zahlenwerten
bezeichnen Dezimalpunkte.
Please read Cautions and warnings and
Important notes at the end of this document.
Page 10 of 11
Important notes
The following applies to all products named in this publication:
1. Some parts of this publication contain statements about the suitability of our products for
certain areas of application. These statements are based on our knowledge of typical requirements that are often placed on our products in the areas of application concerned. We
nevertheless expressly point out that such statements cannot be regarded as binding
statements about the suitability of our products for a particular customer application.
As a rule, EPCOS is either unfamiliar with individual customer applications or less familiar
with them than the customers themselves. For these reasons, it is always ultimately incumbent on the customer to check and decide whether an EPCOS product with the properties described in the product specification is suitable for use in a particular customer application.
2. We also point out that in individual cases, a malfunction of electronic components or
failure before the end of their usual service life cannot be completely ruled out in the
current state of the art, even if they are operated as specified. In customer applications
requiring a very high level of operational safety and especially in customer applications in
which the malfunction or failure of an electronic component could endanger human life or
health (e.g. in accident prevention or lifesaving systems), it must therefore be ensured by
means of suitable design of the customer application or other action taken by the customer
(e.g. installation of protective circuitry or redundancy) that no injury or damage is sustained by
third parties in the event of malfunction or failure of an electronic component.
3. The warnings, cautions and product-specific notes must be observed.
4. In order to satisfy certain technical requirements, some of the products described in this
publication may contain substances subject to restrictions in certain jurisdictions (e.g.
because they are classed as hazardous). Useful information on this will be found in our Material Data Sheets on the Internet (www.epcos.com/material). Should you have any more detailed questions, please contact our sales offices.
5. We constantly strive to improve our products. Consequently, the products described in this
publication may change from time to time. The same is true of the corresponding product
specifications. Please check therefore to what extent product descriptions and specifications
contained in this publication are still applicable before or when you place an order. We also
reserve the right to discontinue production and delivery of products. Consequently, we
cannot guarantee that all products named in this publication will always be available. The
aforementioned does not apply in the case of individual agreements deviating from the foregoing for customer-specific products.
6. Unless otherwise agreed in individual contracts, all orders are subject to the current version of the "General Terms of Delivery for Products and Services in the Electrical Industry" published by the German Electrical and Electronics Industry Association
(ZVEI).
7. The trade names EPCOS, BAOKE, Alu-X, CeraDiode, CSMP, CSSP, CTVS, DSSP,
MiniBlue, MKK, MLSC, MotorCap, PCC, PhaseCap, PhaseCube, PhaseMod, SIFERRIT,
SIFI, SIKOREL, SilverCap, SIMDAD, SIMID, SineFormer, SIOV, SIP5D, SIP5K, ThermoFuse,
WindCap are trademarks registered or pending in Europe and in other countries. Further
information will be found on the Internet at www.epcos.com/trademarks.
Page 11 of 11