20-33-44 Page 4
 C. Procedure

 (1) Installation
 (Ref. Fig. 001, 002)
 (a) Standard installation
 - Use the correct cable tie for the bundle diameter.
 - Put the cable tie around the bundle with the section of the
 locking head outside.
 - Engage the free end of the cable tie into the locking head and
 pull tightly with your hand.
 - Use the applicable wiring tool (guns) (Ref. chapter
 20-25-51/wiring tool).
 Make sure that the gun set is applicable for the bundle
 diameter to be attached.
R  ____NOTE : You must use the correct setting values : if you tighten 
R  too much you will cause damage to the cable ties (break 
R  the head or cause deformation of the strap). If you do not 
R  tighten sufficiently, this is not sufficient for 
R  satisfactory tying operations. 
R  - Put the gun nose near the cable tie locking head and engage the 
R  end of the cable tie.
 - Pull the trigger. The cable tie is tightened and, when you get
 the necessary tension, it is automatically cut and the tail of
 the cable tie is ejected. 
R  - Do a manual check to make sure that the tie is correctly 
R  tightened.
 - Remove and discard the cable tie tail. 
R  - Make sure that the head of the cable tie does not touch an 
R  adjacent bundle. 
R  (b) Special case of coaxial cables
 - Install the coaxial cable on the bundle in the rack.
 Point the head of the cable tie on the bundle at 90. from the
 vertical axis of the coaxial cable added.
 - Put the cable tie in an eight shape to apply the pressure
 equally or put a silicone tape NSA935403 or equivalent (wind
 around 2 times). 
R  Try not to put the cable tie head on the coaxial cable.
 - Set the wiring tool (guns) to minimum tension.
 - Put the gun nose near the cable tie locking head and engage the
 end of the cable tie.
 - Pull the trigger. The cable tie is tightened and, when you get
 the necessary tension, it is automatically cut and the tail of
 the cable tie is ejected.

20-33-44 Page 5

R Tie-wraps - Installation and check NSA935401 Figure 002

20-33-44 Page 620-33-44 Page 7

R R  Do a visual check to make sure that the tie is correctly tightened. - Remove and discard the cable tie tail. 
R R R  (c) Special case of optical fiber cables Optical bundles are tied by lacing tape NSA8420 or cable ties NSA935401-3 after protection by a bushing NSA5539 installed on each optical cable at each attachment point.
R R R  ____NOTE : The position of the cable tie installation guns must be equivalent to position 3 max of gun GS2B so as not to change the optical and mechanical properties of the fiber. 
R R R  When you tie an optical harness to an electrical harness tied by NSA935401, the heads of the ties must not touch the optical harness after installation.
R R  (2) Removal (Ref. Fig. 003) To remove a cable tie with plastic tab, you must cut the locking head without damage to the cables. To remove a cable tie with metallic tab (used before 1991), you must cut the cable tie with scissors held parallel to the cables so that the metallic tab does not fall into the bundle between the cables. Remove and discard the cable tie.

R Tie-wraps - Removal NSA935401 Figure 003

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 _______3. NSA8420 
R R R R In general, cable bundles will be tied : - by NSA8420-3, -4 or -8 in low temperature areas, - by NSA8420-1, -2 or -7 in high temperature areas, In bundles that include several technical harnesses, each one must be attached with lacing tape NSA8420, it is not permitted to use enclosed cable ties NSA935401.
 A. P/N identification  NSA8420  - 1
 ------- -
| | | | | ---------- Dimension code | ------------------- Standard P/N
 B. P/N characteristics
R  (1) Temperature Minimum operating temperature is -55 deg.C (-67.00 deg.F). Maximum operating temperature depends on the dimension code.
 (2) Dimension code

R  ------------------------------------------------------------------------
R  | DIMENSION | TEMPERATURE | DIMENSION | STATE | 
R  | CODE | | (mm) | | 
R  |-------------|---------------------------|---------------|------------| 
R  | 0 | -55.C TO 121.C (249.8.F) | 2.5 (Dia.) | Thread | 
　
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