Figure 2-3 - Electrical Bonding Preparation - Nut Plate; Figure 2-4 - Electrical Bonding Preparation - Bolt/Nut Joint; Table 2-2 - Electrical Bonding - Garmin GFC 500 Maintenance Manual

Aircraft Type
Metallic Airframe
2.4.1 Consideration for Untreated or Bare Dissimilar Metals
The correct material finish is important when mating untreated or bare dissimilar metals.
Materials should be galvanically compatible. When corrosion protection is removed to make an
electrical bond any exposed area after the bond is completed should be protected again.
Additional guidance can be found in SAE ARP 1870 Section 5. Typical electrical bonding
preparation examples are shown in Figure 2-3, Figure 2-4, and Figure 2-5.
Figure 2-3 – Electrical Bonding Preparation – Nut Plate
Figure 2-4 – Electrical Bonding Preparation – Bolt/Nut Joint
GFC 500 Autopilot with ESP Part 23 AML STC Maintenance Manual
190-02291-01
Table 2-2 – Electrical Bonding
Ground Reference
Nearby metal structure for servos
or
Instrument panel for GMC 507
Maximum Resistance Between GFC
500 Equipment Chassis and Ground
Reference (mΩ)
Periodic Test Reconditioned
10.0 2.5
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