PTC thermistors as heating elements
Metallized rectangular disks, 42 V power net
Series/Type: B59044
Date: August 2006
EPCOS AG 2006. Reproduction, publication and dissemination of this publication, enclosures hereto and the
information contained therein without EPCOS' prior express consent is prohibited.
1) Peak value of maximum operating DC voltage, incl. ripple.
Applications
42-V automotive applications
- diesel fuel preheating
- defrosting
- additional cabin heating
Features
Silver metallization
For clamp contacting, not suitable for soldering
Self-regulating
RoHS-compatible
Options
Other dimensions and ratings on request
Delivery mode
Packed in styrofoam trays
Dimensional drawing
Dimensions in mm
General technical data
Max. operating voltage Vmax 50 VDC
Max. operating voltage (t ≤400 ms) Vmax,dyn1) 58 V
Rated voltage VR42 VDC
Breakdown voltage VBD > 100 V
Curvature < 0.05 mm
Operating temperature range (V = 0) Top 40/+200 °C
Operating temperature range (V = VR) Top 25/+125 °C
Tolerance of RR∆RR±50 %
Heating elements B59044
Metallized rectangular disks, 42 V power net R44
Page 2 of 6Please read Important notes and
Cautions and warnings at the end of this document.
1) Measured between points
Electrical specifications and ordering codes
Tref
°C
Rmin
(V = VR)
Ω
Tsurf 1)
(V = VR)
°C
RR
(Vmeas ≤1.5 V)
Ω
Ordering code
120 12 135 40 B59044R0120A010
140 12 155 40 B59044R0140A010
160 10 175 40 B59044R0160A010
Characteristics (typical)
PTC resistance RPTC versus
PTC temperature TPTC
(measured at low signal voltage)
Heating elements B59044
Metallized rectangular disks, 42 V power net R44
Page 3 of 6Please read Important notes and
Cautions and warnings at the end of this document.
Cautions and warnings
General
EPCOS thermistors are designed for specific applications and should not be used for purposes
not identified in our specifications, application notes and data books unless otherwise agreed
with EPCOS during the design-in-phase.
Ensure suitability of thermistor through reliability testing during the design-in phase. The
thermistors should be evaluated taking into consideration worst-case conditions.
Storage
Store thermistors only in original packaging. Do not open the package before storage.
Storage conditions in original packaging: storage temperature 25 °C ... +45 °C, relative
humidity ≤75% annual mean, maximum 95%, dew precipitation is inadmissible.
Avoid contamination of thermistors surface during storage, handling and processing.
Avoid storage of thermistor in harmful environment with effect on function on long-term
operation (examples given under operation precautions).
Use thermistor within 6 months after delivery.
Handling
PTCs must not be dropped. Chip-offs must not be caused during handling of PTCs.
Components must not be touched with bare hands. Gloves are recommended.
Avoid contamination of thermistor surface during handling.
Soldering (where applicable)
Use rosin-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.
Standard PTC heaters are not suitable for soldering.
Mounting
Electrode must not be scratched before/during/after the mounting process.
Contacts and housing used for assembly with thermistor have to be clean before mounting.
Especially grease or oil must be removed.
When PTC thermistors are encapsulated with sealing material, the precautions given in chapter
"Mounting instructions", "Sealing and potting" must be observed.
When the thermistor is mounted, there must not be any foreign body between the electrode of
the thermistor and the clamping contact.
The minimum force of the clamping contacts pressing against the PTC must be 10 N.
During operation, the thermistor’s surface temperature can be very high. Ensure that adjacent
components are placed at a sufficient distance from the thermistor to allow for proper cooling at
the thermistors.
Ensure that adjacent materials are designed for operation at temperatures comparable to the
surface temperature of thermistor. Be sure that surrounding parts and materials can withstand
this temperature.
Avoid contamination of thermistor surface during processing.
Heating elements B59044
Metallized rectangular disks, 42 V power net R44
Page 4 of 6Please read Important notes and
Cautions and warnings at the end of this document.
Operation
Use thermistors only within the specified temperature operating range.
Use thermistors only within the specified voltage and current ranges.
Environmental conditions must not harm the thermistors. Use thermistors only in normal
atmospheric conditions. Avoid use in deoxidizing gases (chlorine gas, hydrogen sulfide gas,
ammonia gas, sulfuric acid gas etc), corrosive agents, humid or salty conditions.Contact with
any liquids and solvents should be prevented.
Be sure to provide an appropriate fail-safe function to prevent secondary product damage
caused by abnormal function (e.g. use VDR for limitation of overvoltage condition).
Heating elements B59044
Metallized rectangular disks, 42 V power net R44
Page 5 of 6Please read Important notes and
Cautions and warnings at the end of this document.
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 passive 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 a passive electronic component
could endanger human life or health (e.g. in accident prevention or life-saving 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 a
passive 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.
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, EPCOS-JONES, Baoke, CeraDiode, CSSP, MLSC, PhaseCap,
PhaseMod, SIFERRIT, SIFI, SIKOREL, SilverCap, SIMID, SIOV, SIP5D, SIP5K, UltraCap,
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.
Important notes
Page 6 of 6
