RTCA DO-160G Section 18: Audio Frequency Conducted Susceptibility - Power Inputs

This test determines whether the equipment will accept frequency components of a magnitude normally expected when the equipment is installed in the aircraft.

This test is performed to determine that the EUT will operate as specified when audio frequency interference is applied to the AC and/or DC power input.  The test setup and procedure are nearly identical to MIL-STD 461F test method CS101, with the only difference being the actual test level and frequency range.  The audio frequency interference is transformer coupled onto each power input lead, and the peak-to-peak voltage level of the interference signal is measured across the power input and return leads.  Test levels are up to 8% of the nominal AC input voltage, and the frequency range is as broad as 10 Hz to 150 kHz.

Equipment Categories

There are three DC power Equipment Categories (R, B, and Z) that indicate the type of power used by the equipment and the type of DC power source with which the equipment is compatible.

Two AC power Equipment Categories are specified (R & K).  Category R is used with an additional designation (a two character code), placed in parenthesis following the Category designator, indicates that the equipment has been tested for use with Constant Frequency (CF), Narrow Variable Frequency (NF), or Wide Variable Frequency (WF).  Category K designates that the EUT has been tested for use with any type of AC power input, and tested to a higher level of voltage distortion than category R.

More about RTCA DO-160 Section 18
More about RTCA DO-160G Section 18