8 Updates You Need to Know for DO-160GDecember 27, 2017
DO-160 outlines current Radio Technical Commission for Aeronautics (RTCA) standards for the environmental testing of avionics hardware. The RTCA published the document’s most recent update, DO-160G, in 2010. Here’s a brief overview of some of its most important changes.
Section 2: Revised Definitions of General Terms
- In DO-160G, equipment tested and qualified to the environmental conditions of one category level are now auto-qualified to less severe categories of the same test.
- This change excludes Category X, which remains reserved for cases where equipment does not fit into any other category.
Section 3: Revised Testing Conditions and Test Equipment Requirements
- Section 3 of DO-160G aligns the minimum interconnecting cable lengths for radiated emissions testing with those listed in Section 21.
- Section 3 also requires the use of special purpose software to place equipment in its most susceptible mode during environmental testing.
Section 16: Revised Power Input Requirements
- DO-160G Section 16 contains an update to the control of inrush current for AC- and DC-powered systems that may introduce reactive loading to the airframe power distribution system.
- Newly added test Category Z expands the list of allowed equipment to include those with different inrush requirements.
- Section 16 also outlines normal steady-state voltage and frequency conditions for single- and three-phase powered equipment.
- Category A(CF) equipment can now perform steady-state testing using the emergency condition levels while meeting the normal pass/fail criteria.
Section 18: Additional Information About Power Inputs and Audio Frequency Conducted Susceptibility Testing
- In DO-160G, a maximum current allowance of 36A (peak-to-peak) replaces the 100-Watt test signal applied power limit.
- As well, Appendix 18 now contains a user’s guide with additional information.
Section 19: Revised Testing for Induced Signal Susceptibility
- Section 19 of DOP-160G now includes electric field-induced testing in its list of requirements.
- This requirement ensures that equipment will meet its specified level of operational performance when exposed to stray electric fields.
Section 20: New Radiated and Conducted Radio Frequency Susceptibility Testing Guidelines
- In DO-160G, radiated susceptibility tests can now be used to evaluate transmitting portable electronic devices (TPEDs).
- DO-160G allows the placement of radiating antennas farther than one meter away from the EUT.
- A “Mode Stirring” technique replaces the “Mode Tuning” technique in the alternative reverberation chamber test method.
- Section 20 now includes a user’s guide on potential field stability issues.
Section 21: Revised Emission of Radio Frequency Energy Limits
- Section 21 covers areas where equipment and its associated wiring may be near VHF and GPS radio receiver antennas, and other areas where little shielding is provided.
- The applicable frequency range for the 100-kHz bandwidth is now 400 MHz – 960MHz, while that of the one MHz resolution is 960 MHz – six GHz.
- Uncorrected 10 kHz bandwidth can no longer be used to measure Category M and H emission notches above 960 MHz. Instead, DO-160G now recommends the use of a low noise preamplifier.
- Values for Category H and P limit notches at 152 MHz are changed from 27 dB to 27.5 dB.
Section 22: Amended Lightning Induced Transient Susceptibility Guidelines
- DO-160G Section 22 clarifies that switching generators require a waveform set designation of Z, except during power line testing.
- The section now includes methods and levels for performing multiple burst testing.
- Pin injection tests can no longer be calibrated using the resistor method — test diagrams have been altered accordingly.
- Section 18’s appendix now contains a user’s guide, while removing guidance material requirements.