EPM Series Application Notes
Rev.3.1 May, 2013
TAMURA CORPORATION
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1.3 AC input DC output
When using an AC input connector and DC output connector, pay attention to the rated voltage and rated current
of the connector.
Consider the input voltage, withstand voltage and safety standard demanded values and provide a clearance
between AC input connector pins.
1.4 Fuse (F101)
Since a fuse is not built into the module (M101), always install a fuse at the Live side to ensure safety.
Select the fuse by considering the normal current, in-rush current, ambient temperature, and other conditions.
(Discharge the capacitors in the circuit fully and consider the conditions at which the circuit impedance is lowest
when there is a thermistor or other element whose resistance value changes with temperature.)
①Select a rated current of 2 or more times the normal current.
②Consider the rated current rate of change by ambient temperature.(At high temperature: Rated voltage drops)
③Check that the in-rush current and normal current are within the
blowout
characteristic curve of the fuse.
④Select a fuse so that in-rush current and normal current can take sufficient margin to a fuse permission I
2
t curve.
A required margin is subject to the influence by temperature conditions, and the influence of the number of times
of incoming current which occurs in an expected life. We recommend you to ask a fuse maker a proper margin.
In order to share an input line and an input electrolytic capacitor with another converter, when selecting a fuse with
the high fusing current characteristic, and a
high-capacity electrolytic capacitor, there is a case which a fuse does
not blow out at the time of abnormalities.
Please perform a safety check enough in such a case.
Noise filter （C101,C103,C104,C105,C203,L101)
1.5.1 C101:X capacitor (Across-the-line capacitor)
・
Select the rated voltage matched to the input voltage specifications.
・
Use a safety standard approved product of each country.
1.5.2 C103,C104,C105,C203： Y capacitor (Line bypass capacitor)
・
Use a safety standard approved product of each country.
・
Be careful of the leakage current specified by each safety standard.
・
With a Class II power supply, when connecting directly between the primary and secondary, use a reinforced
insulation product(Y1 class approved).
・
C203 does not require a safety standard approved product, but since the withstand test voltage applied
between the primary and secondary is divided and applied according to the overall capacitance of C104 and
C105 and the capacitance of C203, pay careful attention to the rated voltage.
・
1.5.3 L101：Common mode choke coil
・
Be careful to confirm the rated temperature specified by the wire type and the bobbin insulation used in the
common choke coil
