Ferrites
RM cores
RM12
Series/Type: B65815E*****087
Date: 2009-10-23
Version: 1
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Identification/Classification 1:
(header 1 + top left header bar) RM cores
Identification/Classification 2:
(header 2 + bottom left header bar) RM12
Ordering code:
(top right header bar) B65815E*****087
Series/Type:
(top right header bar) B65815
Preliminary data (optional):
(if necessary)
Department: SMP IN TCF FER PD
Date: 2009-10-23
EPCOS AG 2009. Reproduction, publication and dissemination of this data sheet, enclosures hereto and the information
contained therein without EPCOS' prior express consent is prohibited.
RM cores B65815E*****087
RM12 B65815
SMP IN TCF FER PD
2009-10-23
Page 2 of 4
Magnetic characteristics (per set)
l/A = 0.39 mm
-1
l
e
= 57 mm
A
e
= 146 mm
2
A
min
= 125 mm
2
V
e
= 8320 mm
3
Approx. weight 45 g/set
Delivery mode sets
Packing
Standard styrofoam tray 300 x 200 x 39 (mm)
Material A
L
value
1)
nH s
mm µ
e
Ordering code
N87 160 ±3% app. 1.30 50 B65815E0160A087
N87 250 ±3% app. 0.70 78 B65815E0250A087
N87 400 ±5% app. 0.35 124 B65887E0400A087
N87 1000 ±5% app. 0.12 311 B65887E1000J087
1) Measurement parameter: 10 kHz, 0.25 mT, 100 turns, room temperature.
A
L
value is measured acc. to IEC62044-2. An appropriate wringing of cores with polished surface is used to improve
reproducibility of the measurement. (It is recommended to rub the mating surfaces themselves six times in a circular or
elliptic arc that matches the core profile before measuring A
L
value).
RM cores B65815E*****087
RM12 B65815
SMP IN TCF FER PD
2009-10-23
Page 3 of 4
Cautions and warnings
Mechanical stress and mounting
Ferrite cores have to meet mechanical requirements during assembly and for a growing number of
applications. Since ferrites are ceramic materials one has to be aware of their special behavior under
mechanical load.
Just like any ceramic material, ferrite cores are brittle and sensitive to any shock, fast changing or
tensile load. Especially fast cooling rates under ultrasonic cleaning, high static and cyclic loads can
cause cracks or failure of the ferrite cores.
For detailed information see Data Book 2007, chapter “General – Definitions, 8.1”.
Effects of core combination on AL value
Stresses in the core affect not only the mechanical but also the magnetic properties. It is apparent
that the initial permeability is dependent on the stress state of the core. The higher the stresses are in
the core, the lower the value for the initial permeability. Thus, the embedding medium should offer the
greatest possible elasticity.
For detailed information see Data Book 2007, chapter “General – Definitions, 8.2”.
Heating up
Ferrites can run hot during operation at higher flux densities and higher frequencies.
NiZn-materials
The magnetic properties of NiZn-materials can change irreversibly when exposed to strong magnetic
fields.
Processing notes
– The start of the winding process should be soft. Otherwise, the flanges may be destroyed.
– Excessive winding forces may damage the flanges or squeeze the tube so that the cores can no
longer be mounted.
– Excessive soldering time at high temperature (>300 °C) may affect coplanarity or pin arrangement.
– Not following the processing notes for soldering of the J-leg terminals may cause solderability
problems at the transformer because of contamination with tin oxide (SnO) from the tin bath or
burned insulation from the wire. For detailed information see Data Book 2007, chapter “Processing
notes, 2.2”.
– The dimensions of the pin hole arrangement are fixed and should be understood as an ideal
recommendation for drilling the printed circuit board. In order to avoid problems when mounting the
transformer, customers should make allowances for manufacturing tolerances in the drilling and
pick-and-place processes by increasing the diameter of the pin holes.
RM cores B65815E*****087
RM12 B65815
SMP IN TCF FER PD
2009-10-23
Page 4 of 4
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 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 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
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contained in this publication are still applicable before or when you place an order.
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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.
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MiniCell, MKK, MLSC, MotorCap, PCC, PhaseCap, PhaseCube, PhaseMod, PhiCap, SIFERRIT,
SIFI, SIKOREL, SilverCap, SIMDAD, SIMID, SineFormer, SIOV, SIP5D, SIP5K, ThermoFuse,
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information will be found on the Internet at www.epcos.com/trademarks.
