3M 7620-T-95 User Manual

™

3M

Cold Shrink QT-III Silicone

Rubber Indoor Termination Kit

With High-K Stress Relief

For Tape Shielded, Wire Shielded and UniShield® Cable

7620-T-95

Instructions

IEEE Std. No. 48

Class 1 Termination
5/8 kV Class
95 kV BIL

F CAUTION

Working around energized systems may cause serious injury or death. Installation should

be performed by personnel familiar with good safety practice in handling electrical
equipment. De-energize and ground all electrical systems before installing product.

March 2013

78-8113-5098-8 Rev F 3

1.0 Kit Contents

3 High–K, Tracking Resistant, Silicone Rubber Terminations

3 Preformed Ground Braids

3 Constant Force Springs

3 3M™ EMI Copper Foil Shielding Tape 1181 Strips, 1/2" x 10"

6 Strips Scotch® Mastic Strip 2230 (black with white release liners, bagged)

1 3M™ Cable Cleaning Preparation Kit CC–2

1 Instruction Sheet

NOTE: Do Not use knives to open plastic bags.

Kit Selection Table

NOTE: Final Determination Factor is cable insulation diameter.

Kit Number

7620-T-95

Primary Insulation

O.D. Range

0.32"– 0.59"

(8,1 – 15,0 mm)

Jacket O.D. Range

0.52" – 0.78"

(13,2 – 19,8 mm)

Table 1

Conductor Size Range (AWG & kcmil)

5 kV
100%
133%

8 kV
100%
133%

8 – 4 8 – 6

2 78-8113-5098-8 Rev F

Instructions For Tape Shielded Cable

2.0 Prepare Cable

2.1 Check to be sure cable size fits within kit range as shown in Table 1.

2.2 Prepare cable using dimensions shown in Figure 1. BE SURE TO ALLOW FOR DEPTH OF TERMINAL

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LUG. If necessary to prevent tape shield from unrolling, hold down edge with a single wrap of 3M

EMI

Copper Foil Shielding Tape 1181.

NOTE: Provide additional 1/4" (6 mm) exposed conductor distance to account for growth during crimping of
ALUMINUM lugs or connectors.

NOTE: It is imperative to remove all remnants of the semi-con layer, even if the semi-con layer comes off as one
layer. There should not be any remaining black areas, or particles, on the cable insulation layer.

®

2.3 Select a Scotch

Mastic Sealing Strip 2230 from kit and remove white release liners. Using light tension, apply

a SINGLE WRAP of mastic around the cable jacket 1/4" (6 mm) from cut edge (Figure 1). Cut off excess.

Jacket Removal Length

Depth Of Terminal Lug + Growth Allowance

6 3/4" (171 mm)

2" (51 mm)

1/4" (6 mm)

1" (25 mm)

Cable Jacket

Semi-Con

Tape Shield

1ST Scotch® Mastic Strip 2230

Figure 1

78-8113-5098-8 Rev F 3

3.0 Install Ground Braid

3.1 Position pre-formed ground braid with short tail over tape shield directly adjacent to cable jacket cut edge.
PLEASE NOTE: The ground braid needs to make full contact with the metallic tape shield. Position long tail of
ground braid, extending over cable jacket with solder block over Scotch
Secure ground braid to cable jacket 3 1/2" (89 mm) from cable semi-con edge using vinyl tape (Figure 2).

NOTE: Position vinyl tape with care, it also serves as a marker for positioning the termination.

3 1/2" (89 mm)

Semi-Con Edge

Tape Shield

Ground Braid

Cable Jacket Edge

Solder Block

1ST Scotch® Mastic Sealing Strip 2230

Vinyl Tape Marker

®

Mastic Sealing Strip 2230 (Figure 2).

Figure 2

3.2 Wrap ground braid around cable tape shield one complete wrap, trim excess to prevent overlap and secure in
place with constant force spring. Wrap spring in same direction as ground braid (Figure 3). Cinch (tighten) the
spring after wrapping the final winding.

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3.3 Select second Scotch

Mastic Sealing Strip 2230 from kit and remove white release liners. Apply a second
SINGLE WRAP of mastic over solder block on ground braid and previously applied mastic (Figure 3).
Cut off excess.

Constant Force Spring

Tape Shield

Ground Braid

1ST Scotch® Mastic Sealing Strip 2230

Solder Block

2ST Scotch® Mastic Sealing Strip 2230

Trim

Cable

Tape

Shield

Ground Braid Leg

Figure 3

4 78-8113-5098-8 Rev F

3.4 Wrap two highly stretched half-lapped layers of electrical grade vinyl tape around Scotch® Mastic Strip 2230,

constant force spring and exposed tape shield (Figure 4).

NOTE: Take care not to cover exposed semi-con insulation shield. A minimum of 3/4" (19 mm) must be exposed.

SPECIAL NOTE FOR CLOTH OR PAPER SEMI-CON INSULATION SHIELD
In cables with cloth or paper semi-conductive shields it is recommended the shield be over wrapped with one

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half-lapped layer of highly stretched semi-conductive rubber tape such as Scotch

Electrical Semi-Conducting

Tape 13.

Semi-Con

Tape Shield

Constant Force Spring

Two Half-Lapped Layers of Electrical Grade Vinyl Tape

Scotch® Mastic Sealing Strip 2230

Vinyl Tape Marker

Figure 4

4.0 Install Lug or Connector

4.1 Check to insure 3M™ Silicone Rubber Termination QT–III termination assembly fits over the selected lug

or connector. If lug or connector (Figure 5) will not fit through the termination core, clean the insulation
(per Step 5.0) and slide termination on cable before installing lug or connector. DO NOT REMOVE CORE

AT THIS TIME.

Clearance

Connector/Lug

Figure 5

NOTE: Refer to pages 17-19 for 3M™ Connector and Lug crimping information.

NOTE: For Aluminum Conductors - Thoroughly wire brush conductor strands to remove aluminum oxide layer.
Immediately insert conductor into lug or connector barrel as far as it will go.

4.2 Position connector or lug and crimp according to manufacturer's directions. Remove excess oxide inhibitor and

sharp crimp flashings following crimping.

5.0 Clean Cable Insulation and Lug or Connector Barrel Using Standard Practice

5.1 Wipe the cable insulation with one of the solvent saturated pads from the 3M™ Cable Cleaning Preparation Kit

CC–2. DO NOT ALLOW SOLVENT TO TOUCH SEMI-CON INSULATION SHIELD!

5.2 If abrasive must be used:

a. Use on insulation only. DO NOT USE ABRASIVE ON SEMI-CON INSULATION SHIELD!
b. Use only aluminum oxide abrasive; grit 120 or finer, included in the 3M
c. Be careful not to reduce the cable insulation diameter below that allowed by the kit.

78-8113-5098-8 Rev F 5

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Cable Cleaning Preparation Kit CC-2.

6.0 Install Termination

6.1 Slide the termination body onto the cable and remove core. Pull while unwinding, counter-clockwise, starting
with the loose end (Figure 6). Make sure the termination body (not the core) is butted up to the edge of the
vinyl tape marker previously applied (Figure 6).

NOTE: Once the termination body makes contact over the mastic seal area, there is no need to continue
supporting the assembly. DO NOT PUSH OR PULL ON THE TERMINATION ASSEMBLY WHILE
UNWINDING THE CORE.

Counter-Clockwise

Vinyl Tape Marker

The material being removed at this step is mixed polymersNOTE:

waste.and can be recycled with

Figure 6

6.2 Connect ground braid to system ground according to standard practice.

Correct Installation of Termination on Tape Shielded Cable

Vinyl Tape
Marker

Ridge at End of Stress
Controlling Compound

Semi-Con Insulation Shield

Stress Controlling Compound

Cable Insulation

Conductor

Ridge at End of Cable
Insulation Shield (Semi-Con)

Environmental Top
Seal

6 78-8113-5098-8 Rev F