Garmin GSU 75 Series Installation Manual page 27

2.11.2.1 Consideration for Wing Grounded Lighting Fixtures
The following installation practices are recommended when installing the GMU 44 in a wing.
1. The wing tip lights should not have a power ground referenced to the chassis of the light assembly
that would then be referenced back to the airframe ground via the light assembly mounting.
2. A dedicated power ground should be used and returned as a twisted pair with the power source
back into the fuselage for a wing mounted GMU 44.
These installation practices will prevent magnetically interfering currents from flowing in the wing skin
that encloses the GMU 44. Electrically isolating the light assembly should not be used as an alternative to
item 1 above, unless the isolated light assembly has been analyzed for adequate protection against direct
attachment of lightning.
2.11.2.2 GMU 44 Location Survey Tool
Refer to "AHRS/Magnetometer Installation Considerations" (190-01051-00) for details regarding the
determination/verification of GMU 44 location using the software program GLS (Garmin Location
Survey) Survey Tool (GPN 006-A0240-00). 190-01051-00 contains information that is generally
applicable but not specific to any particular airframe and is available from the Dealer Resource Center at
www.garmin.com.
190-01639-00
Rev. 6
The document reference is online, please check the correspondence between the online documentation and the printed version.
GSU 75 ADAHRS Installation Manual
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