Tech Tips

Crest factor is found by dividing the peak value of the waveform by the RMS value. If the crest factor is high (in other words, if the waveform has a peak value that is larger than the RMS value), the wave has a sharp peak.

The crest factor also represents the extent of the dynamic range. In addition to the world of electricity, it is also used to determine mechanical events (such as vibration) and the performance of measuring equipment (such as measurement limits).

With power supplies, the crest factor is generally used as an index for the waveform of the input current. In the case of capacitor input power supplies, the crest factor is high (in other words, there is a large peak current), resulting in a power supply with a poor power factor that appears to have a large current value. As a result, it is necessary to provide a greater margin of error for input cables and power facilities.

In order to prevent these drawbacks, you can use a power factor improvement circuit (PFC) to bring the input current close to a sine wave, to lower the peak current and reduce the burden on input cables and power facilities. However, a PFC also has its own efficiency level, so there are both advantages and disadvantages to making this choice. Our sales representative will be happy to suggest power supplies that match your work environment and intended use.