Pontoppidan Callesen posted an update 1 week, 6 days ago
Lightning strokes, which total 200 kA or 300 kV, cause hazards on the equipment or location, so lightning protection is vital for operation.
Let us begin with the first note in regards to what is lightning and why lightning protection can be so important. Principle phenomenon behind lightning is charges accumulated in the cloud as well as the earth are equal and opposite. This forms a non-uniform potential gradient surface in mid-air. Once the gradient is greater than the potential of the surface, the breakdown occurs and a "streamer" flows from your cloud towards the earth.
A direct stroke occurs when the lightning hits the power systems directly how the immense potential will result in destruction in the equipment or even the facility. In contrast, an indirect stroke occurs from the lightning discharges inside the proximity with the power line or from electrostatic discharge for the conductor due to the charged clouds.
The principle power system elements requiring lightning protection are power feeds, home alarm systems, telephone lines, data and control systems and RF cables.
Strategies to Lightning Protection. The rolling sphere way is used for identifying the precise positioning of the lightning and surge protection devices nearby the equipment under operation.
Protection with the power line against direct strokes is through a ground wire or protector tube. The previous produces electrostatic screening, which can be affected by the capacitances in the cloud to line along with the line to ground. The second forms an arc between the electrodes, causing gas deionisation.
Rooftop/Frame Protection. It can be interesting to make note of the building and rooftop frame or cladding is preferably metal than insulation type.
Installing of a finial near the top of the energy tower must have the very least distance of just one.5 m over the highest antenna or lights. This kind of rooftop or building frame is made from reinforced steel for defense purpose.
Wooden towers without downconductors might cause a fireplace hazard, since they route the incoming charges to ground. In principal, for non-metallic roofs, proper downconductors ought to be installed at the appropriate location and height.
Device Protection. Antenna lightning protection is supplied through spark gap, the gas discharge tube and quad-wavelength shorted stub. The very first method uses ball points to ensure if your strike occurs, high potential forms bewteen barefoot and shoes along with the ground. The 2nd method causes gas deionisation through arc formation involving the electrodes. The last method uses a coax transmission line throughout the transmission line so that system bandwidth is narrow.
A lightning arrester is really a device offering lightning protection by regulating spark gaps. The product classification may vary from rod gap, horn gap and valve type to metal oxide lightning arresters.
Earthing and Bonding Solutions. Now learn about how earthing and bonding solutions for lightning protection ought to be afforded. The appearance of earth rods, terminals or clamps must be you might say to route the incoming transients to earth to minimise step and touch potentials. The geometric measurements chosen should comply with the IEEE and NFPA standards. Any earthing system really should have proper bonding, as ground potential rise can’t be compensated. Again, the number of interconnects and spacing must be designed per the lightning standards.
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