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Total Solution to Earthing & Lightning Protection |
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Electronic systems have become central to virtually every
aspect of our lives from PCs and building management
systems in the office to automated petrol pumps and barcode
scanners at the supermarket.
The ever-changing pace of technological development, and
especially the headlong quest for miniaturisation, has
created the scenario where increasingly lightning sensitive
systems are placed at the core of our society.
Most modern electronic systems are at risk including
computers, data communication networks, CCTV
equipment, plant sensors, programmable logic controllers
(PLCs), even uninterruptible power supplies (UPSs).
The seriousness of the consequences of that damage, are
more real than ever before.
The importance of electronic systems protection, often
referred to as surge protection, is now defined in
many standards, including IEC/BS EN 62305 and BS 7671.
Introduction
Electronic systems protection
Transient overvoltages
The main risk to internal systems is through transient
overvoltages - large, very brief and potentially destructive
increases in voltage within the electrical system.
Transient overvoltages can be caused by:
–– The secondary effects of lightning strikes (either between
clouds or to ground) from up to a kilometer away, from
lightning energy induced on to power, data and signal lines
–– Electrical switching of large inductive loads (such as
motors, transformers and electrical drives)
Devastating effects
Transient overvoltages can reach magnitudes of up to
6,000 Volts in a well-insulated 230/400 V power distribution
system, over eight times the level tolerated by many
electronic systems. Although lasting only thousandths or
millionths of a second, without protection they can devastate
modern electronic systems.
Loss of these systems would cripple industrial, commercial
and government organizations alike.
IEC/BS EN 62305 makes clear the need for a combined lightning protection
solution including both structural and electronic systems protection.