Q&A(FAQ) Is it acceptable to apply a 400 Hz input to an AC-DC unit?
Generally, commercial power frequencies are 50 Hz or 60 Hz. However, power generated by a dynamo typically has a frequency of approximately 400 Hz.
COSEL products specify two types of input frequency ranges: 47 to 63 Hz and 47 to 440 Hz.
When a high-frequency input voltage is applied to a power supply specified for 47 to 440 Hz operation, the leakage current may increase; however, normal operation of the power supply is maintained.
A high-frequency input voltage must not be applied to power supplies specified for 47 to 63 Hz operation, as the following issues may occur. Note that power supplies with a built-in Power Factor Correction (PFC) circuit are specified for 47 to 63 Hz operation.
- Reduction in power factor
- Audible noise from the choke coil
- Increase in input current due to resonance within the internal circuit
- Increase in leakage current
If a power supply equipped with a PFC circuit is operated at an input frequency of 400 Hz, its performance characteristics must be carefully evaluated. If such operation is required, please contact us for further guidance.