(b)
Connect the grounding cable to approved grounding attach point on the airplane. These points are identified in Fig. 201.
S 022-023
(2) Before the airplane is moved, remove the ground cables from the approved grounding attach point on the airplane.
TASK 20-41-01-762-024
3. Bonding Procedure_________________
A. Procedure:
S 422-033
WARNING: DO NOT CONNECT A HEADSET AND DO NOT TOUCH CONNECTIONS TO THE
_______ AIRPLANE DURING ATMOSPHERIC ELECTRICAL ACTIVITY OR IN STRONG ELECTROMAGNETIC FIELDS. LIGHTNING STRIKE AND HIGH DISCHARGE CURRENTS CAN CAUSE SEVERE INJURY.
CAUTION: ATTACH BONDING CABLES ONLY TO SPECIFIED POINTS ON THE AIRPLANE.
_______ INCORRECTLY ATTACHED BONDING CABLES CAN CAUSE SCRATCHES WHICH CAN CAUSE CORROSION AND CRACKS ON STRESSED PARTS. BOND WIRES ATTACH TO DOORS OR FAIRINGS MADE FROM COMPOSITE MATERIALS DO NOT PROVIDE A BOND.
(1) Connect a bonding cable to a recognized bonding or grounding point on the airplane and a recognized grounding or bonding point on the support equipment in use.
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747-400 MAINTENANCE MANUAL
S 022-026
(2) Before the airplane is moved, remove the bonding cables from the airplane.
TASK 20-41-01-762-027
4. Measure Airplane Electrical Resistance to Ground________________________________________________
A. Equipment
(1)
Ohmmeter - Multimeter
B.
References
(1)
AMM 24-22-00/201
(2)
AMM 24-41-03/601
C.
Prepare to Check
S 042-028
(1)
Remove electrical power from the airplane (AMM 24-22-00/201).
S 022-039
(2)
Remove or De-energize any External Powered devices.
S 762-034
(3)
Do a continuity check from the neutral pin of th external power receptacle to the grounding stud (AMM 24-41-03/601).
S 022-038
(4)
Disconnect airplane static ground cables if connected.
S 422-029
(5)
Connect a ohmmeter between the recognized bonding/grounding point on one of the Primary Landing gear of the airplane and an identified ground point on the ramp or the surface of the ramp on which the airplane is parked.
S 762-030
(6)
Measure the resistance to ground and record in the maintenance log. Resistance should be less than 1.0 megohms.
S 812-037
(7)
If the resistance exceeds 1.0 megohms this may be the result of inadequate grounding point or exceptional high surface resistance. Do the followings:
NOTE: If the resistance to ground is greater than 1.0 megohms,
____ record this fact in the airplane log book and advise the flight crews of subsequent flights of this airplane that insufficient conductivity to ground is established through the tires to electrostatically ground this airplane on a parking surface and that static gorund procedures may apply.
(a) Ensure the airplane is not parked over painted surfaces and that the tires provide adequate conductivity.
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(b) Repeat the measurement at other parking site locations where successful measurement have been made to verify adequate airplane conductivity.
(8) S 422-035Connect airplane static ground cables if required.
(9) S 862-036Put the Airplane Back to Its Usual Condition
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