There are 50Hz and 60Hz of the commercial rated input frequency. Most of COSEL's power supply must be used at 47 to 63Hz as specs. However, the electrical characteristic like the output voltage and so on does not depend on the change of the input frequency very much. Our products applying to the safety agency approval must be operated at the rated input frequency, if you need the safety agency approval.

1. High input frequency

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. Because the loss of the capacitor and rectifier diode is increased and these make efficiency and power factor low, the power supply should not be used at the input frequency exceeding the spec.

2. Low input frequency

If the power supply is used at the input frequency that is lower than the rated, because charging time is longer than the normal and the input capacitor can not enough charge, the output voltage might be decreased.