Wire Routing And Installation - Garmin GI 275 Installation Manual

4.1 Wire Routing and Installation

GI 275 LRU connector definitions and pin functions are defined in Appendix A. System installation
requires fabrication of electrical wire harnesses. When fabricating and installing each harness:
• Reference the aircraft manufacturer (electrical) standard practices manual and equipment
manufacturer documentation for guidance on wire type, gauge, routing, and wire identification.
Methods, techniques, and practices defined in AC 43.13-1B Chapter 11, Aircraft Electrical
Systems, are acceptable
• Refer to the equipment manufacturer for any specific shield requirements, or follow general
practices and guidance in this manual if none exist
• For all existing wiring that is overbraided, the overbraid must be maintained and include the new
wire added between the GI 275 and the existing system. It is acceptable to install new overbraid
containing the new wire provided that the existing wire and overbraid routing is maintained. The
overbraid should be terminated in the same or better manner at each connector. If pigtails are used,
they should be kept as short as possible and no longer than the original overbraid
• Ensure the wiring does not contact sources of heat or RF/EMI interference (power sources) and is
not routed near moving components of aircraft controls or other systems. Wire routing must
preclude accidental impact or damage
• Provide adequate space for the LRU or sensor connector(s). Include additional wire length to
create a service loop for maintenance, where appropriate
• Shield terminations must be as short as possible and not exceed 3.0 inches unless otherwise
specified. Shields may be connected to the metal connector backshell when the backshell is
grounded to the airframe chassis ground, unless otherwise specified by equipment manufacturer.
Alternately, the shield termination may be directly connected to the airframe ground
• The GEA 24/110 wiring must be routed away from any windows. Installed GI 275s must not share
any circuit breakers or ground returns. The standby instruments must not share any circuit breakers
or ground returns with any GI 275
• When installed as a Primary ADI or Standby ADI, the GI 275 wiring should be routed
independently from the PFD or electronic standby instrument
• Intermediate connections must be minimized to maintain certified electromagnetic compatibility.
All shields must have continuity at intermediate connections (e.g., bulkhead connectors, terminal
blocks, splices, etc.). If intermediate connectors are installed, unless otherwise specified, the shield
must be terminated at both sides of the intermediate connector backshells (if metal connector) or to
airframe ground on both sides of the intermediate connectors
NOTE
Interconnect diagrams in this manual only show end-to-end connections and do not show
intermediate connections that may be present in an aircraft.
190-02246-10
Rev. 11
GI 275 Part 23 AML STC Installation Manual
Page 4-2