Toroids in N30 material

mag

Member
2008-01-23 9:22 pm
Chiasso
Hi all,
I would like to know if the Epcos N30 material is suitable toroids used for SMPS transformer (push-pull).

It is quite hard for me to get toroids in materials other that N30 so I would like to know it these are usables

N30 characteristics

ui=4300
Bmax=380mT
f_min=10kHz
f_max=400kHz
Curie_T=130°C
resistivity=0.5ohm*m

Epcos recommend this material for EMI filter applications

The standard N87 material that Epscos recommends for power electronics applications has the following characteristics

N87 characteristics

ui=2200
Bmax=490mT
f_min=25kHz
f_max=500kHz
Curie_T=210°C
resistivity=10ohm*m

My main concern is the core resistivity, 20 times lower than N87 which will create high losses due to eddy currents.
The value of Bmax is lower but I can always wind more turn on the trafo to lower B.

Do you think that these toroid core are usable for SMPS?

thank you
 
I have used 3E25 toroids, a material similar to N30, withot problems. The drawbacks are that you have to use a few more turns and a slightly lower frequency, but it's fine otherwise.

Try to search further, I think that there are online stores selling toroid cores made from power ferrite materials (not from EPCOS or Ferroxcube, but from Magnetics, Micrometals, MMG...)
 

QSI

Member
2008-03-10 8:42 pm
PIN OUT color code from PCB

i was wondering what the color code is for the +12V and +5V out from the PCB to the multi pin connector in the MX9000 power supply. here is what i know so far:

brown = ground
green\yellow = earth
orange = +18V
blue = -18V
purple = +48V
red = +12V or +5V, not sure
black = ground
yellow = +12V or +5V, not sure

can anybody help? i saw the pic from an earlier post but it was the side of the PCB i already know is good!

thanks