Cosel is one of the world's leading power supply manufacturers offering
high-quality, ultra small size AC-DC power supplies,
DC-DC converters of the state-of-the-art technologies, and effective and
easy-to-use noise filters.

 Generally, the commercial frequency is 50Hz or 60Hz. However, the voltage which is from dynamo, its frequency is around 400Hz.
There are two types of the input frequency spec in COSEL's products. One is 47 to 63Hz, and the other is 47 to 440Hz.

 If the input voltage with high frequency is applied to the power supply in which spec is 47 to 440Hz, the leakage current could increase. However the operation of the power supply is normal.
 The input voltage with high frequency can not be applied to the power supply in which spec is 47 to 63Hz, because there is possibility that the problems as the following occur. Incidentally, the spec of PFC (Power Factor Correction) circuit built-in power supply is 47 to 63Hz.

* Power factor decreases
* Produce a sound from choke coil
* The input current increases because the resonance occurs in the internal circuit
* The leakage current increases

 If the power supply that has the PFC circuit is used at 400Hz of input frequency, it is required to consider the behavior of characteristics. If you need to use the power supply as above, please contact us.