1 Round Robin Test Results Matthew Wills Electrical Lab Manger Nhi Dinh Electrical Engineering Student Assistant Wichita State University Nick Conquest Research Engineer

2 Round Robin Test Results Participants Cessna Aircraft Co. Cobham Technical Services DLS Electronic Systems Elite Electronic Engineering, Inc. EMC Partner Electronics Test Center National Institute for Aviation Research Rockwell Collins Thermo Fisher DnB Boeing Environ Thank you to all labs that participated!

3 Data Set 12 companies participated in the testing. Data was gathered from 25 different generators. Multiple companies use a separate generator to produce WFM-1 and WFM1/WFM2. 13 generators were “Custom Built” (DIY) 12 generators were off the shelf (OTS)

4 Generator Types ID#Generator TypeID#Generator Type Generator 1DIYGenerator 14DIY Generator 2OTS 1Generator 15DIY? Generator 3OTS 1Generator 16DIY? Generator 4OTS 1Generator 17OTS1 Generator 5OTS 2Generator 18OTS3 Generator 6OTS 2Generator 19DIY Generator 7OTS 1Generator 20DIY Generator 8DIYGenerator 21DIY Generator 9OTS 2Generator 22DIY Generator 10DIYGenerator 23OTS1 Generator 11DIYGenerator 24OTS3 Generator 12DIYGenerator 25OTS2 Generator 13DIY OTS – Commercial Off the Shelf DIY- Do it Yourself – Lab Built

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14 Round Robin Test Summary DC resistance data was consistent across all test boxes and test houses. Data on unshielded cabling and power lines with reasonable amount of impedance was very consistent. Voltage levels or limits are always obtained along with a low current and small standard deviation in current/voltage data. Data on shielded and hybrid bundles show a lot of variation depending on the generator used. Standard deviation of current on shielded and hybrid bundles was above 100A. Labs were instructed to run the test as they would a standard DO- 160 test. – Some labs reran the testing with a different generator when the test level could not be reached, others did not. – This may simply be a “communication” error from the Working Group to the participants.

15 Round Robin Test Summary Continued DIY generators typically showed variations OTS generators of the same manufacturer typically gave similar results (likely due to similar generator source impedance) Source impedance shown to be a determining factor on current/voltage measured on shielded and hybrid bundles. (Can be seen specifically in Generators 19-22, which are the same generator with different source impedance)

16 Plans for Next Round of Testing What is an acceptable tolerance? Determine generator source impedance during calibration? (i.e. Isc along with Voc at same generator output setting) – Will show variation between generator source impedances to help determine a tolerance between what is an acceptable test level. Changes to Test boxes? Remove Shields? Specific points of measurement?