Maximum electrostatic noise
rejection is achieved by shielding the cable with aluminium-mylar
tape. An overall shield is normally provided and in critical applications
an individual shield over each pair or triad is also provided. A
minimum of 25% overlap of the shield ensures 100% coverage even
when the cable is flexed. The drain wire under the shield provides
continuous low resistance path to ground and simplified hook-up
at grounding terminals. The cables can also be provided with copper
braid screening.
Ease of installation is another major benefit of these cables.
Individual cores, pairs, triads or quads are colour coded and or
number printed. A pair of communication wires can also be provided.
The cables are available in a wide range of insulation and jacket
materials, the most popular being PVC, Polyethylene, HR PVC, FRLS
PVC, ZHLSF, Silicone, EPR & CSP rubber, Teflon.
The detailed construction, conductor sizes and electrical characteristics
are as mentioned below. The company also manufactures custom designed
cables to meet the specific requirements of individual customer
applications.
 Conductor
Bare / tinned electrolytic annealed copper conductor. Solid, stranded
or flexible confirming to BS 6360 and IS 8130. Refer Table 1 for
details.
Insulation
PVC or HR PVC insulation in accordance with IS 5831. Polyethylene
insulation in accordance with BS 6234 / IS 6474.
Twisting
and Laying
Required numbers of cores are laid up in case of multicore core
cables. Individual pairs, triads or quads are formed by uniformly
twisting the insulated cores with short lay lengths, prior to laying.
Core
Identification
Cores can be colour coded or number printed for easy identification.
In case of multi pair cables one core in each pair is number printed
in words as well as in figures at short intervals of 50mm or a numbered
polyester tape is provided over each pair.
Overall
Screen
After final lay up of the complete cable an overall screen of aluminium-polyester
tape is applied along with 0.5 sqmm multi stranded annealed tinned
copper (ATC) drain wire in continuous electrical contact with aluminium
side of the tape. Tinned copper braid screening can also be provided.
Individual
& Overall Screen
Individual pairs, triads or quads are screened by aluminium-polyester
tape along with 0.5 sqmm ATC drain wire and overall screened by
aluminium-polyester tape as mentioned above. Tinned copper braid
screening can also be provided.
In case of individually screened cables for critical applications
an extruded isolation sheath can also be provided over the individual
screens.
Assembly
Binder
After final assembly a non-hygroscopic polyester tape is provided
to act as a binder as well as a bedding for the outer screening
in all cables.
Armour
Galvanized steel round wire or strip armour in accordance with BS
5308 / IS 1554 respectively. The armour wire and strip confirms
to IS 3975. If required, G.I square interlock armour or G.I / S.S
wire braid armour can also be provided.
Inner
& Outer Sheath
PVC, HR, FRLS PVC or ZHLSF sheath in accordance with IS 5831 can
be provided. U.V stabilized Polyethylene sheath can also be provided
for hazardous areas. A blue colour outer sheath for intrinsically
safe areas can be provided on request. A pair of communication wires
can be provided if desired.
|
| DETAILS
OF CONDUCTOR & INSULATION |
|
|
Nominal
Cond.
Area |
Nominal
Cond.
Strands |
Approx.
Cond.
Diameter |
Max Cond Res. @ 20°C |
Nominal
Insulation
Thick. |
Nominal
Core
Diameter |
| Bare
Copper |
Tinned
Copper |
| Sqmm |
No./mm |
mm |
ohms/km |
ohms/km |
mm |
mm |
| 0.5 |
1/0.8 |
0.80 |
36.0 |
36.7 |
0.5 |
1.80 |
| 0.5 |
7/0.3 |
0.90 |
36.0 |
36.7 |
0.6 |
2.10 |
| 0.5 |
16/0.2 |
1.00 |
39.0 |
40.1 |
0.6 |
2.20 |
| 0.75 |
1/0.98 |
1.00 |
24.5 |
24.8 |
0.6 |
2.20 |
| 0.75 |
7/0.37 |
1.10 |
24.5 |
24.8 |
0.6 |
2.30 |
| 0.75 |
24/0.2 |
1.20 |
26.0 |
26.7 |
0.6 |
2.40 |
| 1.00 |
1/1.13 |
1.10 |
18.1 |
18.2 |
0.6 |
2.30 |
| 1.00 |
7/0.43 |
1.30 |
18.1 |
18.2 |
0.6 |
2.50 |
| 1.00 |
32/0.2 |
1.40 |
19.5 |
20.0 |
0.6 |
2.60 |
| 1.5 |
1/1.38 |
1.40 |
12.10 |
12.2 |
0.6 |
2.60 |
| 1.5 |
7/0.53 |
1.60 |
12.10 |
12.2 |
0.6 |
2.80 |
| 1.5 |
48/0.2 |
1.60 |
13.30 |
13.7 |
0.6 |
2.80 |
| 2.5 |
1/1.78 |
1.80 |
7.41 |
7.56 |
0.6 |
3.00 |
| 2.5 |
7/0.67 |
2.00 |
7.41 |
7.56 |
0.6 |
3.20 |
| 2.5 |
80/0.2 |
2.00 |
7.98 |
8.21 |
0.6 |
3.20 |
|
|
| ELECTRICAL
CHARACTERISTICS |
|
|
Sl. |
Parameters |
Units |
PVC Insulated |
P.E Insulated |
|
1. |
Max. Conductor Resistance |
Ohms/km |
Refer Table 1 |
|
2. |
Minimum Insulation Resistance |
Mohms/km |
25 |
5000 |
|
3. |
Max. Mutual Capacitance @1KHz Core to core |
pF/mtr |
250 |
75 |
|
For 1.5mm² |
250 |
85 |
|
4. |
Max. Capacitance, core to screen |
pF/mtr |
400 |
115 |
|
5. |
Max. L/R Ratio |
µH/ohm |
25 |
25 |
|
For 1.5mm² |
40 |
40 |
|
For 2.5mm² |
70 |
70 |
|
6. |
Max. Mutual Inductance |
mH/km |
1.0 |
|
7. |
High Voltage Tests: |
|
Spark Test |
Volts |
4000 |
|
Core to Core |
Volts |
1500 |
|
Core to Screen |
Volts |
1000 |
|
Screen to Armour |
Volts |
500 |
|
Screen to Screen (optional) |
Volts |
125 |
|
|
