(2)
SWPM (applicable procedure)
(3)
WDM (applicable diagram)
C. Procedure
S 862-002
(1)
Attach a DO-NOT-CLOSE tag to the tripped circuit breaker.
(2)
Install a circuit breaker lock on the tripped circuit breaker.
S 862-004
(3)
If the tripped circuit breaker is one of three circuit breakers protecting a 3-phase circuit:
S 862-003
(a) Open the other two circuit breakers.
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(b)
Attach DO-NOT-CLOSE tags.
(c)
Install circuit breaker locks.
S 862-005
(4) Look in the aircraft logbook to find if there is recorded data about a "tripped" circuit breaker, such as:
(a)
The condition existing when the circuit breaker trip occurred.
(b)
The conditions existing when the circuit breaker was reset.
(c)
The results of resetting the circuit breaker.
S 862-006
(5) Do a visual check for damage to electrical wiring and system components related to the tripped circuit breaker. If necessary, refer to the Wiring Diagram Manual (WDM). Look for these types of damage:
(a)
Electrical shorting
(b)
Electrical arcing
(c)
Corrosion on the contacts of the electrical wiring and system components
(d)
Abrasion of the electrical wiring and system components
(e)
Cracks on the insulation of the electrical wiring
(f)
Split wires
NOTE: A split wire is when you can see the conductor through
____ the crack in the insulation of the electrical wiring.
(g)
Broken wires
(h)
Discoloration of the insulation of the electrical wiring
(i)
Fluid or dust contamination of electrical wiring and system components
NOTE: Contamination can be a fuel source during electrical
____
arcing.
(j) Metal shavings
NOTE: Metal shavings can cause electrical shorting.
____
S 862-007
(6) Make sure that there are no loose terminal connections.
NOTE: Loose terminal connections can be a source of electrical
____
arcing.
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(7) S 862-008If you find damage to the electrical wiring, refer to the Standard Wiring Practices Manual (SWPM) and repair the electrical wiring.
(8) S 862-009If you find damage to a system component, refer to the applicable Aircraft Maintenance Manual (AMM) procedure and replace the component.
(9) S 862-010Remove contamination and metal shavings if necessary.
S 862-011
(10)
Remove the DO-NOT-CLOSE tag(s).
S 862-012
(11)
Remove the circuit breaker lock(s).
S 862-013
WARNING: KEEP PERSONS AND EQUIPMENT CLEAR OF THE SYSTEM RELATED TO THE
_______ TRIPPED CIRCUIT BREAKER. MAKE SURE THAT THERE IS NO DAMAGE TO THE ELECTRICAL WIRING AND SYSTEM COMPONENTS. MAKE SURE THAT ALL TERMINAL CONNECTIONS ARE TIGHT. DAMAGED ELECTRICAL WIRING, DAMAGED SYSTEM COMPONENTS AND LOOSE TERMINAL CONNECTIONS CAN CAUSE ELECTRICAL ARCING AND A FIRE WHEN THE CIRCUIT BREAKER IS CLOSED.
IF THE TRIPPED CIRCUIT BREAKER IS RELATED TO THE FUEL SYSTEM, OBEY CHAPTER 28 OF THE AIRCAFT MAINTENANCE MANUAL AND THE FAULT ISOLATION MANUAL. THERE ARE PROCEDURES IN CHAPTER 28 THAT DO NOT ALLOW THE RESETTING OF TRIPPED CIRCUIT BREAKERS. ELECTRICAL ARCING CAN CAUSE IGNITION OF FUEL OR FUEL VAPORS AND THE RESULT CAN BE A FIRE OR EXPLOSION.
(12)
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