Datasheet

Dielectric Constant
Table 2 shows the dielectric constant versus
temperature of 70 Tape. This test was run
according to ASTM-D-150-68 at a stress of
50 V/mil and a frequency of 60 cycles per
second.
DIELECTRIC CONSTANT
VS. TEMPERATURE,
SCOTCH 70 TAPE
6.0 Performance Tests
Termination Tracking Test
Reduced-dimension terminations are
prepared according to 3M print 2047-B-16
(See Figure 1). Each specimen consists of 8
feet of 15 kV cable and two terminations.
The contaminant employed in this test is the
formula called out in ASTM Dust and Fog
Test D-2132, as shown below:
Flint (SiO
2
floated) 240 mesh 85 parts
Clay 325 mesh 9 parts
Salt (Na Cl) technical grade 3 parts
Paper, filter pulp 3 parts
all by weight
This mixture is then ball milled using 3/4-
inch diameter ceramic cylinder. The milled
dust is then mixed with equal parts by
weight of water to make a slurry of paint
consistency.
Next, each termination is carefully coated in
such a manner as to deposit a uniform and
reproducible amount of contamination. The
following procedure is used:
1. Mix the slurry thoroughly.
2. Submerge the inverted termination into
the slurry.
3. Withdraw the termination from the
slurry, taking care not to throw off too
much excess slurry in rotating the
termination from the inverted to an
upright position. The majority of the
excess slurry should drain off when the
termination is upright.
operated either outdoors or in areas
subjected to contamination or moisture, shall
be overwrapped with at least one layer of
Scotch 70 Silicone Rubber Electrical Tape.
All splices on spacer cable operating at 15
kV and above shall be overwrapped with
Scotch 70 Silicone Rubber Electrical Tape.
All splices on silicone rubber cables or other
cables which can operate at room
temperatures in excess of 130°C/266°F, but
not exceeding 180°C/266°F, shall use Scotch
70 Silicone Rubber Electrical Tape as the
primary insulating material.
5.0 Characteristics and Test Data
Typical Electrical and Physical Properties
Dissipation Factor
Table 1 shows the dissipation factor versus
temperature of 70 Tape. This test was run
according to ASTM-D-150-68 at a stress of
50 V/mil and a frequency of 60 cycles per
second.
DISSIPATION FACTOR
VS. TEMPERATURE,
SCOTCH 70 TAPE
Physical Properties
Color Munsell 5BG7.0/0.4
Sky Blue Gray
Thickness
ASTM-D-1000-76 .012 in.
Tensile Strength
ASTM-D-1000-76 12 lbs./in.
Elongation at Break
ASTM-D-1000-76 450%
Electrical Properties
Dielectrical Strength
ASTM-D-1000-76 875 V/mil
Arc Resistance
ASTM-D-495-71 1 min. (minimum)
TEMPERATURE DISSIPATION
(°C/°F) FACTOR (%)
23/73 1.3%
90/194 1.1%
130/266 0.5%
150/302 0.7%
Table 1
TEMPERATURE DIELECTRIC
(°C/°F) CONSTANT
23/73 3.03
90/194 2.89
130/266 2.60
150/302 2.51
Table 2