3M QT-III User manual

3
Cold Shrink Silicone Rubber
Termination QT-III
7672-S-8-TS
Instructions
IEEE Std. No. 48-1996
Class 1 Termination
69 kV Class 350 kV BIL
IEC 60840
72,5 kV
Kit Contents:
1 Silicone Rubber Lug Seal Insulator Assembly
1 Hi-K Stress Control Assembly
1 Silicone Rubber Insulator Assembly
1 Silicone Rubber Skirted Insulator Assembly
1 Pre-formed Ground Braid Assembly
3 Constant Force Springs
1 Roll Scotch®Electrical Shielding Tape 24
6 Tubes P55/R Red Compound (Non-Silicone Grease)
1 Roll Scotch®Sealing Mastic 2229, 1" (25 mm) wide
8 Strips Hi-K Mastic (1-6" ×22", 7-2" × 11")
1 Roll Scotch®Silicone Rubber Tape 70
1 Roll Scotch®Vinyl Electrical Tape Super 88, 1½" ×44'
1 6" (150 mm) Hi-K Mastic Pad
1 3M™Cable Cleaning Pads CC-3
1 Copper Foil Tape Strip 1181, 15" long
4 Instruction Sheets
Note: Do not use knives to open plastic bags.
Kit Number Primary Insulation
O.D. Range Jacket O.D. Range Conductor Size Range AWG (mm2)
7672-S-8 1.94"–3.08"
(49.3–75.4 mm)
2.45"–3.35"
(62.2–85.1 mm)
250–1750
(120–850)
Table 1
4APE3HIELDED#ABLE
3M™Cold Shrink Silicone Rubber
Skirted Termination Kit QT-III
for Tape Shielded Cable
7672-S-8-TS
78-8126-9537-3-B
m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.

2 78-8126-9537-3-B
Correct Installation of Termination
(IGH+3TRESS#ONTROL-ASTIC
(IGH+3TRESS
#ONTROL-ASTIC
(IGH+3TRESS
#ONTROL-ASTIC
(IGH+3TRESS
#ONTROL4UBE
(IGH+3TRESS
#ONTROL4UBE
3ILICONE2UBBER
4UBULAR)NSULATOR
3ILICONE2UBBER
3KIRTED)NSULATOR!SSEMBLY
3ILICONE2UBBER
,UG3EAL4UBE
3ILICONE2UBBER
4UBULAR)NSULATOR
3ILICONE2UBBER
3KIRTED)NSULATOR
!SSEMBLY
(IGH+3TRESS
#ONTROL-ASTIC
(IGH+3TRESS
#ONTROL4UBE
3ILICONE2UBBER
4UBULAR)NSULATOR
3ILICONE2UBBER
3KIRTED)NSULATOR!SSEMBLY
3ILICONE2UBBER
,UG3EAL4UBE
3EMI#ON)NSULATION3HIELD
3EMI#ON
)NSULATION
3HIELD
3ILICONE2UBBER
3KIRTED)NSULATOR!SSEMBLY
3ILICONE2UBBER
4UBULAR)NSULATOR
!
! " #
" #

78-8126-9537-3-B 3
Note: Check to insure all of the 3M™ Termination Assemblies QT-III will fit over the lug. If the lug will not fit through
the assembly cores, this termination can not be installed using this lug. Do not remove any of the cores at this time.
1.0 Prepare Cable
1.1 Check to be sure the cable fits within the kit ranges as shown in Table 1.
1.2 Prepare cable using dimensions shown in Figure 1. Be sure to allow for depth of terminal lug plus 0.5"
(13 mm) plus crimp growth.
Note: Provide additional exposed conductor to allow for growth of aluminum lugs or connectors during crimping.
Conductor Size 250–350 400–650 750–1000 1100–2000
Growth Allowance 0.25" (6 mm) 0.5" (13 mm) 0.75" (19 mm) Field Determined
Table 2

MM

MM

MM
4APE3HIELD
$EPTH
OFLUG
MM
CRIMPGROWTH
)NSULATION
#ONDUCTOR
#ABLE*ACKET
3EMI#ON

MM

MM
Figure 1

4 78-8126-9537-3-B
2.0 Install Ground Braid Assembly
2.1 Select the pre-formed ground braid assembly from the kit. Pass the end of the cable through the ground braid
assembly loop, and position the ground braid assembly around the tape shield shown. (Figure 2)
4APE3HIELD
)NSULATION
#ABLE*ACKET%DGE
3OLDER"LOCK
'ROUND"RAID!SSEMBLY
3EMI#ON
Figure 2
2.2 Select the 3 constant force springs from the kit. Starting at the loop of the ground braid assembly nearest the
cable jacket edge, install the 3 constant force springs, one around each ground braid loop. Cinch (tighten) the
springs after wrapping the final turn. Extend the ground braid tails down the cable jacket. (Figure 3)
#ONSTANT&ORCE3PRING
#ABLE*ACKET%DGE
3OLDER"LOCK
'ROUND"RAID!SSEMBLY
#ABLE)NSULATION3EMICON
Figure 3
2.3 Select the roll of 1" ( 25 mm) wide Scotch® Sealing Mastic 2229 from the kit. Cut a length of the tape long
enough to wrap around the cable jacket. Remove the release liner from the mastic and, using light tension, apply
a single wrap of mastic around the cable jacket, positioned under the ground braid solder blocks. (Figure 4)

78-8126-9537-3-B 5
2.4 Secure the two tails of the ground braid assembly to the cable jacket approximately 6 inches (150 mm) from the
cable jacket edge with several wraps of vinyl tape. (Figure 4)
#ONSTANT&ORCE3PRINGS
6INYL4APE7RAP
3OLDER"LOCK
ST-ASTIC3TRIP
BENEATHSOLDERBLOCKS
MM
APPROX
Figure 4
2.5 Cut four 1" (25 mm) lengths of 1" ( 25 mm) wide Scotch® Sealing Mastic 2229. Remove the release liner and roll
each mastic strip into a small roll. (Figure 5) Press the mastic rolls into place on either side of the ground braid
solder blocks. (Figure 6)
-ASTIC3TRIP -ASTIC2OLLED5P
MM
Figure 5
3OLDER"LOCK
ST-ASTIC3TRIP
BENEATHSOLDERBLOCKS
2OLLED-ASTICX
#ABLE)NSULATION3EMICON
Figure 6

6 78-8126-9537-3-B
2.6 Select the roll of 1" (25 mm) wide Scotch® Sealing Mastic 2229 from the kit and cut a length of the mastic.
Using light tension, apply a single wrap of mastic around the cable jacket over the ground braid solder blocks
and the previously applied mastic. (Figure 7)
ND-ASTIC3TRIP
OVERSOLDERBLOCKSMASTICROLLS
Figure 7
2.7 Wrap two half-lapped layers of highly-tensioned Scotch® Vinyl Electrical Tape Super 88 over the mastic seal and
constant force springs. Cover all exposed mastic, constant force springs and tape shield, overlapping 0.25" (6
mm) onto the exposed cable semi-con. (Figure 8)
Note: Take care not to cover the exposed semi-con. A minimum of 2.5" (75 mm) of semi-con must be exposed.
#ABLE*ACKET
/VERLAP3EMI#ON
MM
6INYL4APE 3EMI#ON
Figure 8

78-8126-9537-3-B 7
3.0 Install Lug or Connector
3.1 Check to be sure the cable fits within the kit ranges as shown in Table 1.
3.2 Position lug/connector and crimp according to manufacturer’s directions. Remove excess oxide inhibitor and
sharp crimp flashing following crimping. Refer to page 14 for 3M lug/connector crimping information up to
1000 kcmil.
4.0 Clean Cable Insulation and Lug Barrel Using Standard Practice
4.1 Use only aluminum oxide abrasive to finish and polish insulation surface.
4.2 Use abrasive only on cable insulation. Do not use on semi-con.
4.3 When using abrasive, do not reduce the cable insulation diameter below that allowed by the kit.
4.4 Wipe the cable insulation clean with an approved solvent. Do not allow the solvent to touch semi-con
insulation shield.
Note: Remove any remaining solvent with 3M™CC-DRY Cable Cleaning Pads (not supplied with kit) or
lint-free cloth.

8 78-8126-9537-3-B
5.0 Install Termination
5.1 Select the large hi-K mastic pad from the kit. Remove the liners and align the pad with 1" (25 mm) covering the
semi-con, and 5" (127 mm) covering the cable insulation. Using light tension, wrap the pad around the cable
insulation two times. Trim the pad to overlap the start by approximately 0.25" (6 mm). Taper the pad edge by
gently pressing along the edge with your finger. (Figure 9)
3EMI#ON
4APER%DGE
#ABLE)NSULATION
#ABLE)NSULATION
(I+-ASTIC0AD
(I+-ASTIC0AD
,AYERS

MM

MM
Figure 9
5.2 Wrap two half-lapped layers of highly-tensioned Scotch® Vinyl Electrical Tape Super 88 over the hi-K mastic
pad, leaving approximately 0.125" (3 mm) of mastic exposed at each end. Taper the exposed edges of the hi-K
mastic onto the cable by gently pressing along the edge with your finger. (Figure 10)
3EMI#ON #ABLE)NSULATION
6INYL
4APE
4APER%DGEOF
(I+-ASTIC
4APER%DGEOF
(I+-ASTIC
MM MM
Figure 10

78-8126-9537-3-B 9
5.3 Starting 5" (127 mm) from the cut end of the insulation, apply 2 tubes of P55/R Red Compund (non-silicone
grease) over exposed insulation and vinyl tape-wrapped mastic pad. (Figure 11)
#OATWITH
022ED#OMPOUND

MM
#ABLE)NSULATION
Figure 11
5.4 Select the Stress Control Assembly (medium length tubular assembly on white core) from the kit. Slide the
Stress Control Assembly over the lug and cable with the loose core end toward the lug. Align the Stress Control
Assembly (not the core) with the end of the tape shield, and remove the core by pulling the loose end while
unwinding counter-clockwise. Clean exposed cable insulation after installation. (Figure 12)
5NWINDCOUNTERCLOCKWISE
#ABLE*ACKET
3TRESS#ONTROL!SSEMBLY
!LIGNWITHENDOF
LONGITUDINALLYCORRUGATEDSHIELD
Figure 12
5.5 Select one 2' x 11" (50 mm x 280 mm) hi-K mastic strip from the kit. Remove the liners and wrap around the
end of the stress control assembly tube and cable insulation. Position the hi-K mastic so that half covers the
stress control assembly tube, and half covers the cable insulation. (Figure 13)
#ABLE)NSULATION
3TRESS#ONTROL!SSEMBLY4UBE
(I+-ASTIC
Figure 13

10 78-8126-9537-3-B
5.6 Wrap two half-lapped layers of highly-tensioned Scotch® Vinyl Electrical Tape Super 88 over the hi-K mastic,
leaving approximately 0.125" (3 mm) of mastic exposed at each end. Taper the exposed edges of the hi-K
mastic onto the cable by gently pressing along the edge with your finger. (Figure 14)
6INYL
4APE
MM MM
4APER%DGEOF
(I+-ASTIC
4APER%DGEOF
(I+-ASTIC
3TRESS#ONTROL
!SSEMBLY4UBE
#ABLE)NSULATION
Figure 14
5.7 Select one or more of the 2" x 11" (50 mm x 280 mm) hi-K mastic strips from the kit. Remove the liner and
fold the mastic strip twice lengthwise to form a 0.5" (12 mm) wide strip. (Figure 15)
(I+-ASTIC -ASTIC&OLDED
/VER4WICE
2EMOVE,INER
Figure 15
5.8 Wrap the mastic strip around the exposed conductor between the cable insulation and lug. Build the mastic up
to the insulation O.D. (Figure 16)
$OUBLED/VER
(I+-ASTIC
Figure 16