For - Mains Powered, Communications Appliances
THUNDERSTORMS:
The number of thunderstorms per year in Australia can be found in the ‘Average Annual Thunder-Day Map supplied by The Bureau of Meteorology.
http://www.bom.gov.au/climate/averages/climatology/thunder/explain_otd_ngnt.pdf
LIGHTNING STRIKE (DIRECT):
A direct strike to power or to communications cables near a building will usually cause major damage to connected appliances.
LIGHTNING STRIKE(INDIRECT):
When lightning strikes a tree or object near a building, it produces electric current in the ground which enters the building through metal connections; i.e. Electrical, Telephone, Water and Gas: Also, via the concrete floor, metal frame and metal reinforcing.
The intensity of a lightning strike and the ability of the soil to disperse the electric current, will determine how far from the strike point that appliances might be affected.
RISK ASSESSMENT:
Thunderstorm-frequency, Building-density, Soil-type and Terrain-exposure will determine your risk level. Generally, equipment in an isolated building on hilly terrain, which is exposed to thunderstorms, has a high risk of damage.
See Australian Standard: AS4262.1—1995 for risk assessment chart.
Appliances that have both mains power and external metallic communications lines are at the highest risk of damage.
TELEPHONE SYSTEM, FACSIMILE, MODEM, CORDLESS PHONE
ANSWER MACHINE, SECURITY, FIRE ALARM, COMPUTER NETWORK
RISK MANAGEMENT:
Damage may cause instant failure, or appear later as software or hardware problems in unprotected appliances. This damage is mostly preventable with the use of Over-voltage Protection Modules, which combine suitable surge diverting and surge blocking devices. The surge diverters cause the lightning current to bypass the equipment and flow safely away through metallic connections or cables, while the surge blocking devices complement the operation of the surge diverters.
THUNDERSTORMS:
The number of thunderstorms per year in Australia can be found in the ‘Average Annual Thunder-Day Map supplied by The Bureau of Meteorology.
http://www.bom.gov.au/climate/averages/climatology/thunder/explain_otd_ngnt.pdf
LIGHTNING STRIKE (DIRECT):
A direct strike to power or to communications cables near a building will usually cause major damage to connected appliances.
LIGHTNING STRIKE(INDIRECT):
When lightning strikes a tree or object near a building, it produces electric current in the ground which enters the building through metal connections; i.e. Electrical, Telephone, Water and Gas: Also, via the concrete floor, metal frame and metal reinforcing.
The intensity of a lightning strike and the ability of the soil to disperse the electric current, will determine how far from the strike point that appliances might be affected.
RISK ASSESSMENT:
Thunderstorm-frequency, Building-density, Soil-type and Terrain-exposure will determine your risk level. Generally, equipment in an isolated building on hilly terrain, which is exposed to thunderstorms, has a high risk of damage.
See Australian Standard: AS4262.1—1995 for risk assessment chart.
Appliances that have both mains power and external metallic communications lines are at the highest risk of damage.
TELEPHONE SYSTEM, FACSIMILE, MODEM, CORDLESS PHONE
ANSWER MACHINE, SECURITY, FIRE ALARM, COMPUTER NETWORK
RISK MANAGEMENT:
Damage may cause instant failure, or appear later as software or hardware problems in unprotected appliances. This damage is mostly preventable with the use of Over-voltage Protection Modules, which combine suitable surge diverting and surge blocking devices. The surge diverters cause the lightning current to bypass the equipment and flow safely away through metallic connections or cables, while the surge blocking devices complement the operation of the surge diverters.
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