Line Clears and Precautions
In the course of your work, you would be supervising technical personnel working on various electric lines. Therefore, you should be aware of the associated precautions. We begin with safety around overhead lines.
Safety around Overhead Lines
Overhead power lines are not insulated and looks can be deceiving. What may appear as insulation is weatherproofing material. Wires should not be touched under ANY circumstances.
There is a minimum safe distance which should be maintained when working near energized power lines and you have read about it in the previous section.
Note that the minimum safe distance increases as the voltage increases. Safe distances also can be affected by weather conditions and other factors. Additional minimum safe distances for various voltages are shown in Table.
Table: Minimum Safe Distances around Overhead Power Lines
We now elaborate the other safety precautions in which required to be observed.
1. Till a Line Clear (LC) is received from all sources each line or equipment should be treated as live.
No person should get up a pole or work on any lines or equipment unless s/he is specifically authorized to do so. Line clears could be issued or received just through authorized persons. While it is not probable to receive or return line clear in person, the similar could be completed over telephone but clear identity through way of voice and also a code should be followed. Adequate clearance among lines on that work is being done and other live wires should be ensured or line clears taken on those lines also.
2. While issuing line clear
- switch off supply and ensure which the work spot where LC is requisitioned is disconnected from all probable sources of supply;
- ensure personally which all blades of all operating switches are open; and
- discharge the line / equipment by using properly earthed discharge rods and through wearing rubber gloves / gauntlets.
3. While returning line clear
- Only the person who acquired the line clear could return the same;
- The person returning the line clear should ensure in which the line /equipment is clear of all people, materials and earthing;
- inform all colleagues in which the LC is being returned and that it is no safer to work on in which line/equipment;
- person receiving back the LC should ensure in which no more LCs are pending return; and - the whole team of personnel should stay back until such time as the line/equipment is recharged and leave the work spot only after recharging.
You might such to go by the following check list before you allow your technicians to work on electric lines.
An LC Form requires be filling up and signing through an authorized person.