1. Select rated voltage
1) The rated voltage is the operating voltage of the power EMI filter used at the specified power frequency, and it is also the high allowable voltage value of the filter. If used in a 50Hz single-phase power filter, the rated voltage is 250V;
2) Filter used in 50Hz three-phase power supply, with a rated voltage of 440V If the voltage of the input filter is too high, it will damage the internal capacitor.
2. Rated current
Rated current (Ir) is the maximum continuous operating current allowed under rated voltage and specified ambient temperature conditions. As the ambient temperature increases, or due to copper loss in the inductor wire, magnetic core loss, and surrounding environmental temperature, the operating temperature is higher than room temperature, making it difficult to ensure the performance of insertion loss. Changzhou Feishuo power filter manufacturer recommends selecting the rated current of the filter based on the actual maximum possible working current and working environment temperature.
3. Insertion loss
Definition of Insertion Loss: Insertion loss is one of the most important technical parameters of EMI power filters. The central issue considered by designers and engineering practitioners is to achieve the highest possible insertion loss while ensuring the safety, environmental, mechanical, and reliability performance of the filter meets relevant standard requirements.
4. Selection of external dimensions
Before selecting, attention should also be paid to the external dimensions and installation hole spacing. This can prevent the purchased filters from being unable to be installed.
The selection of connection methods for filters generally includes lead connections, copper screw connections (be careful not to buy iron ones), PCB pin filters, IEC socket filters, and solder joint connections with copper bars.
