ERICO-Six Point Protection Plan for Lightning, Surge Protection and Earthing
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The six point protection plan for lightning, surge protection and earthing by JR Gumley, Erico Technologies Lightning and overcurrent/overvoltage transients cause millions of dollars damage internationally to cellular radio and telecommunications installations each year. Whilst there is no single technology that can prevent damage, a Six Point Protection Plan is the best check list to cover all damage mechanisms. The plan takes account of surge protection devices (SPDs) and their placement according to the type of power distribution used by the facility. Damage to equipment in the US alone was estimated at US$1,2 billion annually, before including the loss of productivity from industrial and business downtime. In this article, we consider as an example then, a typical telecommunications installation. High energy overvoltage transients may be derived from direct lightning strikes to antenna towers or they may be conducted on power and telephone cables entering buildings and facilities. Induced transient overvoltages may also originate from near strikes due to capacitive or inductive coupling. • peak currents can exceed 200 kA with 10/350 μ s waveshape (SABS IEC 61024-1) • current rise times vary between 0.1 - 100 μ s • rnultipulse surges are experienced in over 70% of direct strike situations. This is a naturally occurring phenomenon where up to 20 restrikes may follow the path of the main discharge at intervals of 10-200 ms • continuing currents of 200 - 500 A lasting 1-2 seconds may also occur Telecommunications radio sites are particularly vulnerable to lightning and transients as they are sited in elevated locations for the best radio signal propagation. This means the towers are often located on mountain tops and on the top of tall buildings - where lightning is looking for the easiest path to ground! In addition to lightning surges, isolated stations at the end of long distribution lines are also prone to suffer equipment damage due to temporary overvoltages caused by switching surges or poor power supply regulation. There is no single technology that can eliminate the risk of lightning and its transients. A holistic systems approach is required. From over 20 years' experience in examining the nature and extent of damage created by lightning transients, Erico Lightning Technologies has developed a comprehensive Six Point Plan to minimise exposure to damage.
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ERICO-Six Point Protection Plan for Lightning, Surge Protection and Earthing
Transcript of ERICO-Six Point Protection Plan for Lightning, Surge Protection and Earthing
The six point protection plan for lightning,surge protection and earthing
by JR Gumley, Erico Technologies
Lightning and overcurrent/overvoltage transients cause millions of dollars damage internationally tocellular radio and telecommunications installations each year. Whilst there is no single technologythat can prevent damage, a Six Point Protection Plan is the best check list to cover all damagemechanisms. The plan takes account of surge protection devices (SPDs) and their placementaccording to the type of power distribution used by the facility.
Damage to equipment in the US alone was estimated at US$1,2 billion annually, before includingthe loss of productivity from industrial and business downtime. In this article, we consider as anexample then, a typical telecommunications installation.
High energy overvoltage transients may be derived from direct lightning strikes to antenna towersor they may be conducted on power and telephone cables entering buildings and facilities. Inducedtransient overvoltages may also originate from near strikes due to capacitive or inductive coupling.
• peak currents can exceed 200 kA with 10/350 μs waveshape (SABS IEC 61024-1)• current rise times vary between 0.1 - 100 μs• rnultipulse surges are experienced in over 70% of direct strike situations.
This is a naturally occurring phenomenon where up to 20 restrikes may follow the path ofthe main discharge at intervals of 10-200 ms
• continuing currents of 200 - 500 A lasting 1-2 seconds may also occur
Telecommunications radio sites are particularly vulnerable to lightning and transients as they aresited in elevated locations for the best radio signal propagation.This means the towers are often located on mountain tops and on the top of tall buildings - wherelightning is looking for the easiest path to ground! In addition to lightning surges, isolated stationsat the end of long distribution lines are also prone to suffer equipment damage due to temporaryovervoltages caused by switching surges or poor power supply regulation.
There is no single technology that can eliminate the risk of lightning and its transients. A holisticsystems approach is required. From over 20 years' experience in examining the nature and extent ofdamage created by lightning transients, Erico Lightning Technologies has developed acomprehensive Six Point Plan to minimise exposure to damage.
The Six Point Plan recommends:
• capture the direct lightning strike at a preferred point on purpose-designed air terminals
• conduct the lightning current to earth safely via a purpose-designed downconductor system tominimise the dangers of side-flashing
• dissipate the energy into the earth with minimal rise in ground potential through a lowimpedance grounding system
• eliminate earth loops and differentials by creating an equipotential grounding plane undertransient conditions
• protect equipment from surges and transients on power lines
• protect equipment from surges and transients on communications and signal lines to preventequipment damage and costly operational downtime
