System for guiding a dielectric cable from phase-to-ground potential
A system is provided for guiding a dielectric cable from a conductor to an elevated support structure. The system comprises: an insulator arranged to be attached to a conductor. The insulator comprises a first bore for receiving a dielectric cable. The system further comprises an earth bond extending to a lower end of the insulator; and a downpipe extending between first and second ends. The first end of the downpipe is connected to the lower end of the insulator and the second end of the downpipe is arranged to be supported by an elevated support structure. The downpipe is for receiving the dielectric cable from the bore of the insulator.
1. A system for guiding a dielectric cable from a conductor to an elevated support structure comprising:
an insulator arranged to be attached to a conductor comprising a first bore for receiving a dielectric cable;
an earth bond extending to a lower end of the insulator; and
a downpipe extending between first and second ends, the first end connected to the lower end of the insulator and the second end arranged to be supported by an elevated support structure, the downpipe for receiving the dielectric cable from the bore of the insulator,
wherein the downpipe is formed of a flexible material.
2. The system of claim 1 , further comprising:
a dielectric cable extending through the bore of the insulator and the downpipe; and
an insulating material filling a space between an inner surface of the bore and the dielectric cable.
3. The system of claim 1 , wherein the insulator further comprises a second bore for receiving a second dielectric cable.
4. The system of claim 1 , wherein the downpipe supports the earth bond in its extension to the insulator.
5. The system of claim 1 , wherein the insulator has a rating which exceeds a transmission voltage of the conductor.
6. The system of claim 5 , wherein the insulator has a length selected to define its rating.
7. The system of claim 1 , wherein the insulator has a length of less than 600 millimetres.
8. The system of claim 1 , wherein the insulator is formed of a plurality of insulator sections, each insulator sections comprising:
a first end flange;
a second end flange; and
a central portion connecting the first and second end flanges, the central portion narrower than the first and second end flanges,
wherein the first end flange comprises a plurality of clearance holes, and the second end flange comprises a plurality of tapped holes corresponding in location to the clearance holes, each for receiving a screw passing through the corresponding clearance hole to connect adjacent insulator sections to form the insulator.
9. The system of claim 8 , wherein each insulator section is rated for between 33 and 40 kilovolts.
10. The system of claim 8 , wherein each insulator section is rated for 35 kilovolts.
11. The system of claim 1 , wherein the insulator has a length of less than 500 millimetres.
12. The system of claim 1 , wherein the insulator has a length of less than 400 millimetres.
13. The system of claim 1 , wherein the earth bond extends through or is attached to the downpipe.
14. The system of claim 1 , wherein the insulator has a rating which is between 100% and 110% of the transmission voltage.
15. The system of claim 14 , wherein the insulator has a length selected to define its rating.
16. A method of installing a system for guiding a dielectric cable from a conductor to an elevated support structure comprising the steps of:
attaching an insulator comprising a bore to a conductor;
connecting an earth bond to the insulator;
passing a dielectric cable through the bore;
cutting a downpipe to a length for bridging a distance between a lower end of the insulator and an elevated support structure;
passing the dielectric cable through the downpipe; and
attaching a first end of the downpipe to the lower end of the insulator and a second end of the downpipe to the elevated support structure.
17. The method of claim 16 , further comprising the step of:
filling a space between the dielectric cable and the inner surface of the bore with a liquid insulating material which sets over a given period to a gel.