AE Techron T2000 Low-Frequency Conducted Susceptibility Transformer

RTCA/DO-160 Section 16 test procedures are used to determine whether the EUT can operate during different AC and/or DC power variations that occur during normal and emergency aircraft operation. RTCA/DO-160 Section 16 tests verify whether the equipment will negatively affect the aircraft power system that would be harmful or degrade performance in other equipment. These tests cover both susceptibility (surge, dropout, frequency transients, etc.) and harmful interference (current harmonics, re-generated energy, power factor, etc.) of the EUT.   Tests: DC Input tests Steady-state over- and under-voltage conditions Ripple voltage Momentary power interruption Momentary sags and surges Exposed voltage decay time (270 V only) Inrush current AC Input tests Steady-state over- and under-voltage conditions Steady-state over- and under-frequency conditions Steady-state phase unbalance (three-phase power) Voltage and frequency modulation Voltage and frequency transients Momentary power interruption Momentary sags and surges DC offset and voltage distortion Harmonic current emissions Phase unbalance (3 phase inputs) DC current content Inrush current Current modulation Power factor Equipment Categories According to RTCA/DO-160 Section 16, there are four Equipment Categories (A, B, D, or Z) that indicate the type of power used by the equipment and the type of AC and/or DC power source with which the equipment is compatible. For AC powered equipment, an additional designator, placed in parenthesis following the Category designator, is a two-character code indicating that the equipment has been tested for use with Constant Frequency (CF), Narrow Variable Frequency (NF), or Wide Variable Frequency (WF). Up to four additional category designators are also used to indicate testing for: AC current harmonics (H) AC current modulation (L) AC power factor (P) DC current ripple (R) AC or DC inrush

RTCA/DO-160 Section 18 provides test procedures to determine if the EUT will operate as specified when audio frequency interference is applied to the AC and/or DC power input. RTCA/DO-160 Section 18 is similar MIL-STD 461F test method CS101 with the only difference being test level and frequency range. The EUT must be tested while operating at both minimum and maximum current draw (if applicable), and at the AC power frequency extremes if designated for use with Variable Frequency systems when testing to RTCA/DO-160 Section 18 requirements. 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. AC Power Equipment Categories are specified as R and 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. RTCA/DO-160 provides standard procedures and environmental test criteria for testing airborne equipment for the entire spectrum of aircraft from light, general aviation aircraft and helicopters through the "jumbo jets" and SST categories of aircraft. The tests outlined in this standard are performed to meet FAA and international regulations for electrical and electronic equipment installed on commercial aircraft. RTCA/DO-160 G is the current version of this standard. Coordinated with EUROCAE, RTCA/DO-160G and EUROCAE/ED-14G are identically worded. DO-160G is recognized by the International Organization for Standardization (ISO) as de facto international standard ISO-7137.  

MIL-STD-461G CS101 applies from 30 Hz to 150 kHz for equipment and subsystem AC, limited to current draws ≤ 30 amperes per phase, and DC input power leads, not including returns. MIL-STD-461G CS101 is also applicable to systems that draw more than 30 amps if the system has an operating frequency of 150 kHz or less and an operating sensitivity of 1 μV or better (such as 0.5 μV). If the EUT is DC operated, MIL-STD-461G CS101 requirement applies over the frequency range of 30 Hz to 150 kHz. If the EUT is AC operated, this requirement applies to start from the second harmonic of the EUT power frequency and extending to 150 kHz.  This test procedure is used to verify the ability of the EUT to withstand signals coupled onto input power leads. There are two methods provided for making measurements of the applied signal. The first uses an oscilloscope with a power input isolation transformer. The second uses a measurement receiver together with a transducer. The transducer electrically isolates the receiver from the EUT power and reduces the levels to protect the receiver.   Test Equipment The test equipment shall be as follows: Signal generator Power amplifier Oscilloscope or measurement receiver Coupling transformer Capacitor, 10 μF Isolation transformer for oscilloscope use or transducer for measurement receiver use Resistor, 0.5 ohm LISNs   Procedures The test procedures shall be as follows: a. Turn on the measurement equipment and allow sufficient time for stabilization. b. Calibration. (1) Set the signal generator to the lowest test frequency. (2) Increase the applied signal until the oscilloscope or measurement receiver indicates the voltage level corresponding to the maximum required power level specified for the limit on Figure CS101-2. Verify the output waveform is sinusoidal for oscilloscope measurements. (3) Record the setting of the signal source. (4) Scan the required frequency