(4) Wind the piece of the metal overbraid with insulating tape.
(a) Wind the metal overbraid with a layer of insulating tape.
(b) Each wind must overlap the last wrap by 50 percent.
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(c) Wind another layer of insulating tape over the metal overbraid in the opposite direction of the first wind.
(d) The wind should extend 1 in. (25.3999 mm) and 1.5 in. (38.0999 mm) beyond the end of the repair area on both sides.
(5) Tie the insulating tape with tying tape.
(a) The ties should be spaced 0.5 in. (12.6999 mm) apart and extend across the repair area.
(b) For the tie use a clove hitch and a square knot.
11. Harness Outer Jacket Repair___________________________ (Ref. Fig. 006)
A. Procedure
(1) Tie the harness outer jacket at the open end near the repair area with tying tape.
(2) Add at least two ties at each end.
(3) The ties should be spaced 0.5 in. (12.6999 mm) apart.
(4) For the tie use a clove hitch and a square knot.
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How to Wrap the Repair Area
Figure 006
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E E Aug 01/04 E E ECES E HARNESS GENERAL - DESCRIPTION AND OPERATION
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1. Description
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A. Introduction:
(1) The engine harnesses interconnect the airframe with the electrical components mounted on the engine. These harnesses provide electrical power to the various components. They also provide circuits for the transmission of signals for engine monitoring functions.
(2) Some of the harnesses are named for engine functions and others are named for the engine or thrust reverser to which they apply.
(3) New generation computer controlled engines and increased use of composite materials significantly impacted the make of the electrical harnesses built by Rohr Inc. for the various Nacelle systems.
(4) The more severe requirements for today's harnesses require:
(a) A high degree of extremely reliable lightning and electromagnetic interference (EMI) protection,
(b) Operation in sustained higher temperature environments,
(c) Line replacement and connector replacement capability.
(5) These requirements along with fluid resistance and chafe constructions have resulted in the current band/boot make approved. This type of construction results in a highly reliable harness assembly.
B. Harness Construction:
(Ref. Fig. 001)
(1) The electrical harnesses have wires with one, two, or three conductors which are shielded. The wire shields are grounded by being attached to the connector backshell. The wires are then covered with a metal shield.
(2) The metal overbraid prevents the wires from lightning hits:
- The metal overbraid is put on the harness by a machine
- The overbraid is made of nickel plated copper
- The overbraid is attached to the connector adapter by a tie-dex band.
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Harness Construction
Figure 001
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E E Feb 01/01 E E ECES E E 56-5B E E E (3) The connectors on the harnesses have backshell adapters:
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- The backshell adapters provide a metal surface for the ground of the wire shields and the metal overbraid.
- The backshell attaches to the connector.
- The connector is attached to the equipment.
- The equipment is grounded by touching the aircraft structure or by bonding straps.
(4) The outer jacket of the harness prevents the harness from fluid contamination and wear. The outer jacket is sealed at each connector with a protective boot. Where the wires of the harness go in a different direction, the jacket is sealed with a transition fitting.
(5) Each connector on the harness is identified with a Functional Identification Number (FIN). The FIN is on an identification sleeve which is located near the connector:
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