Lightning equipotential bonding
Equipotential bonding simply the electrical
interconnection all appropriate metallic
installations/parts, such that the event of
lightning currents flowing, metallic part at
a different voltage potential with respect one
another. The gas,
water and central heating system are all bonded
directly the equipotential bonding bar located
inside but close outer wall near ground level.Internal LPS design considerations
The fundamental role the internal LPS to
ensure the avoidance dangerous sparking
occurring within the structure protected.
The power cable bonded via suitable SPD,
upstream from the electric meter, the
equipotential bonding bar.43) shows typical example an
equipotential bonding arrangement. larger extended structures
several bonding bars may required but they
should all interconnected with each other.
This electrical interconnection can achieved by
natural/fortuitous bonding using specific
bonding conductors that are sized according
to Tables and IEC/BS 62305-3.
Bonding can also accomplished the use
of surge protective devices (SPDs) where the
direct connection with bonding conductors is
not suitable.
The Figure below (which based IEC/BS EN
62305-3 fig E.
—
01 Example main
equipotential bonding.
The screen any antenna cable along with any
shielded power supply electronic appliances
being routed into the structure should also be
bonded the equipotential bar. This bonding bar
should located close the main distribution
board (MDB) and also closely connected the
earth termination system with short length
conductors. the metallic parts are essentially at
the same potential then the risk sparking or
flashover nullified.
Carrying out appropriate equipotential bonding
measures ensuring there sufficient
electrical insulation distance between the
metallic parts can avoid dangerous sparking
between different metallic parts.
This could due, following lightning discharge,
to lightning current flowing the external LPS or
indeed other conductive parts the structure
and attempting flash spark over internal
metallic installations.
—
01
Equipotential
bonding bar
Structural lightning
protection system
Central heating system
Screen antenna cable
Electronic appliances
Power from utility
Meter
Meter
Gas
Water
Electricity
meter
Consumer unit/
fuseboard
ON
OFF
Neutral bar
Live bar
115
TECHNICAL REFERENCE IEC/BS 62305-3 PHYSICAL DAMAGE STRUCTURES LIFE HAZARD
