1. Rated Voltage The voltage when EMI filter is working under the appointed frequency.(250V, 50Hz in China; 230V, 50Hz in Europe, 115V, 60Hz in the United States)

2. Rated Current The maximal allowable continuous current (Imax) when EMI filter is working under rated voltage and appointed environment temperature (it’s 40℃ if not appointed specially). The allowable Imax in the specific temperature is a function and can be got by the formula like this.

3. Test Voltage The voltage applied between the appointed terminals in the specific time. There are two kinds of test voltage. One is line-to-line test voltage that is applied between two terminals of the EMI filter. Another is line-to-earth test voltage that is applied between one terminal and the case or specific terminal. 

4. Leakage Current A current which passes through phase line or neutral line to the ground at the rated voltage, Directly related to the capacitance to ground in the filter. calculated by the formula: ILC=2×π× F×C×V F= Line frequency C= Capacitance V= L-G voltage

5. Insertion Loss It’s a general measure of a filter's performance. It’s the ability of EMI filter to attenuate interference signal. It is the ratio of the signal voltage between the terminals before and after the insertion of EMI filter. When the source impedance equals to the load impedance of 50Ω , insertion loss can be expressed in terms of the voltages like: IL=20Lg(E0/E1) IL-Insertion Loss(dB) E0-The voltage between terminals before the insertion of EMI filter (V) E1-The voltage between terminals after the insertion of EMI filter (V)

6. IEC Climatic Category It means the EMI filter’s working Climatic Category. According to the IEC, the letters of the climatic classification are coded as follows: XX/XXX/XX First letter: lowest working temperature Middle letter: highest working termperature Last letter: the testing days for the type test

7. Insulation Resistance 2 It’s the resistance between line or neutral line to the ground. Generally, we use special insulation resistance meter to test it.

8. ElectroMagnetic Interference (EMI) This term is often used interchangeably with RFI (radio-frequency-interference). Technically, EMI refers to the type of energy (electromagnetic), while RFI refers to the frequency range of the noise frequency). Our filters are used to eliminate the unwanted signals of both EMI and RFI.

9. FREQUENCY RANGE Generally, the band of frequencies of electromagnetic energy expressed in Hz (cycles per second), kHz (thousand of cycles per second). The typical frequency range of power line filter’s attenuation is 150kHz to 30MHz (above 30 MHz noise mainly is radiated).

10. Impedance mismatch A filter works best when its impedance in the RFI frequency range on the line and load side is greatly different from the impedance on the line and load circuits to to which it is connected. This is called impedance mismatch.