Magnetics Epcos (Siemens Matsushita Components), Germany TDK Ferroxcube
North West Laboratory

Engineering Center SZL and LEPCOS
— General representative of Epcos AG by ferrite in the CIS
— Official distributor and general representative for ferrites of
    TDK Electronics Europe Gmbh in the CIS
— Authorized distributor of Magnetics in Russia, CIS and Baltic countries
— Exclusive distributor of USM in Russia and CIS countries
— Official Distributor Temex Ceramics in Russia and CIS
Products » Magnetics Cores » Powder Cores » Ring Cores » Magnetics cores marking »

Magnetics cores marking

The example of identification in technical documentation: MPP125 R20,3*12,6*6,35 C055206-A2

Color marking

Cores produced by Magnetics have a coating with a special composition which provides a reliable protection against moisture and chemical influence. and is characterized by with improved dielectric properties.Materials coatings have their own color code:

Material Coating color The last symbols of the part number
MPP gray A2, A5, A9, D4, M4, W4, L6
High Flux хаки A2, A5, A9
Kool Mμ black A7

Dielectric coating characteristics

Magnetics toroidal powder cores are coated with a special epoxy finish that provides a tough, moisture and chemical resistant barrier having excellent dielectric properties. Toroids up to 16.5 mm OD can also be parylene coated. Toroids as larger as 16.5 mm OD can be coated with parylene to minimize the construction of ID. All finished dimensions in the catalog are for the epoxy coating (A2 or A7 in the part number). The maximum steady-state operating temperature for epoxy coating is 200°C. The maximum steady-state operating temperature for parylene is 130°C, but it can be used as high as 200°C for short periods, such as during board soldering. High temperature operation of Magnetics poweder cores does not affect magnetic properties. MPP, Kool M μ ,High Flux XFlux, Kool Mμ MAX, can be operated at 200°C with no aging or damage.

The finish is tested for voltage breakdown by inserting a core between two weighted wire mesh pads. Force is adjusted to produced a uniform pressure of 10 psi, simulating winding pressure. The test condition for each core in the random sample set, to guarantee minimum breakdown voltage in each production batch, is 60 Hz rms voltage at 1.25 the guaranteed limit. A2 and A7 samples (26.9 mm and larger) are tested to 2500V min wire-to-wire. AY samples are tested to 750 V min wire-to-wire.

For a parylene coated toroid (AY), the maximum OD and HT are reduced by 0.18 mm )0.007"), and the minimum ID is increased by 0.18 mm (0.007").

Core inductance tolerance and grading

Magnetics powder cores are precision manufactured to an inductance tolerance of AL ±8%. (first digits of part number are 00). At the request of the customer, cores with an OD more than 5 mm can be delivered with a tolerance of AL ± 2% (first digits of a part number are C0). Almost all sizes of ring cores made of MPP are generally produced with a tolerance of AL ± 2%.

Graded Magnetics MPP cores and High Flux cores are also available with tolerances tighter than the standard ±8%.

Different types of temperature stabilization

MPP cores produced by Magnetics with three types of temperature stabilization are available: standard, controlled and linear.

Last symbols of a part number Stabilization type AL tolerance Controlled temperature range Breakdown voltage
D4 Controlled ±0,1% от 0°C до + 55°C 500 V
W4 Controlled ±0,25% от -55°C до +85°C 500 V
M4 Controlled ±0,25% от -65°C до +125°C 500 V
L6 Linear See figures от -55°C до +85°C 500 V

Standard cores are marked with last symbols of a pat number, such as A2, A5 и A9 (The difference is in breakdown voltage value)

To create high-precision inductors, cores with controlled and linear stabilization are recommended (the last symbols of the code are D4, M4, W4 and L6, respectively).

09.10 19 

LEPCOS invites you to attend the Stand C23 at ChipEXPO 2019 exhibition, which will be held from 16 to 18 October 2019 in Moscow in the Expocentre, in the pavilion "Forum".


26.06 19 
According to the results of 2018 Lepcos has received "best ferrites seller 2018" seal of excellence from TDK company.

18.04 19 
Dear colleagues! We would like to draw your attention to the fact that, since December 2018, the package content of electrolytic capacitors has been changed.


«North West Laboratory» © 1999—2020

Development & support — Marina Kutuzova