8
Power Supply
Technical Information
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Harmonic Current Suppression
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What is Harmonic Current?
Most switch-mode power supplies incorporate capacitors. As a
result, the input voltage sine wave is transformed into steep input
current pulses.
If this current is provided to the power-receiving equipment of
factories or buildings, the equipment will generate excessive heat
that may damage the equipment itself, while also consuming
unnecessary energy. This has become a public problem as well.
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Harmonic Current Control
As an international standard, IEC555-2 was enacted for the
limitation of harmonic current emission. IEC1000-3-2, as a
revised standard replacing IEC555-2, was established in 1994.
In conformance with the IEC1000-3-2, EN61000-3-2 was
established and will come into effect in European countries in
January 2001 Power Supplies with a capacity of 75 W or higher.
In Japan, the Ministry of International Trade and Industry
provided some guidelines for the suppression of harmonics
generated from electrical household appliances and electrical
equipment. Japanese manufacturers have been voluntarily
issuing and abiding by the guidelines.
•
Main Applicable Models
S82K-P
@@@
24 (200-V Series only)
S8TS
S8VS
S8VM
Note. Buzzing Noise when Turning ON Input
A noise may occur when turning ON the input of models incorporating
harmonic current suppression circuits. This is a transient noise that
occurs only until the internal voltage has stabilized and does not indicate
any problem in the product.
Main Applicable Models: S8TS
S8VS (120, 180, 240 W)
S8VM (50, 100, 150 W)
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Life Expectancy
The life of a Power Supply is determined by conducting a
temperature rise test of the built-in aluminum electrolytical
capacitors, when using the Power Supply in a standard
installation at the rated input voltage under an ambient
temperature of 40
°
C and a load rate of 50%. The calculated life
expectancy functions as a guide only is not a guaranteed value.
Use this information as reference for performing maintenance
and replacement.
Note. The life expectancy of the fan in models with fans is not included.
(Main Models)
Eight years or longer: S82K
Ten years or longer: S82J, S8TS, S8VS, S8VM
Input voltage
Input current
