Furse Total Solution to Earthing & Lightning Protection

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Total Solution to Earthing & Lightning Protection | 9AKK106354A3360 10/11
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Tested in line with the IEC/BS EN standards series, ESP
protection can be selected and applied to
IEC/BS EN 62305 and BS 7671 easily using the SPD
product application tables and data sheets. Key product
and application features are represented using the
following symbols:
Lightning Protection Zone (LPZ) details the
boundary (to IEC/BS EN 62305-4) or installation
point of the SPD. For example, LPZ 0 - 3 signifies
that the SPD can be installed at the service
entrance boundary and create an immediate LPZ
3 suitable for protecting electronic equipment
close to the SPD installation.
Equipment further downstream of this location
may require additional protection, against
switching transients for example.
Mains Test Type defines the Type of mains SPD
(BS EN 61643 Type 1, 2, 3 or I, II, III to IEC 61643)
tested with the respective test Class I (high
energy 10/350 μs current waveform), II (8/20 μs
current waveform) or III (combined 8/20 μs current
and 1.2/50 μs voltage waveform) from the
IEC/ BS EN 61643 series.
Where more than one Type is stated (for
combined, enhanced Type SPDs), the SPD has
been tested to each respective test Class, with
the results detailed on its transient performance
specification.
Signal/Telecom Test Category indicates the
Test Categories (as defined in IEC/BS EN 61643
series) that SPDs for signal and telecom systems
have been subject to, with the results detailed on
the transient performance specification.
Test Category D is a high-energy test typically
using the 10/350 μs current waveform. Test
Category C is a fast rate of rise test using the
1.2/50 μs voltage waveform combined with 8/20
μs current waveform. Test Category B is a slow
rate of rise test using the 10/700 μs waveform,
also used within ITU standards. Enhanced SPDs
tested with categories D, C and B can offer up to
LPZ 0 →3 protection.
Electronic systems protection
Simplified product selection
All Furse ESP products are designed to provide simple system integration whilst
achieving highest levels of effective protection against transients.
Common Mode signifies that the SPD specifically
offers protection on conductors with respect to
earth. For a mains system, this would be between
phases and earth or neutral and earth. For a
data/telecom line this would be between signal
line(s) to earth.
Common mode surges can result in flashover if
the insulation withstand voltage of connected
wiring or equipment is exceeded. Flashover could
lead to dangerous sparking potentially causing
fire or electric shock risks. Equipotentially bonding
Type 1 mains SPDs or Test Cat D tested signal/
telecom SPDs reduce the risk of flashover by
limiting common mode surges.
Full Mode means that the SPD protects in all
possible modes; common mode (live conductors
with respect to earth) and differential mode
(between live conductors). For example, Full Mode
mains SPDs offer protection between phase(s)
to earth, phase(s) to neutral and neutral to earth.
Whilst common mode protection ensures
flashover is prevented, differential mode
protection is critical to ensure sensitive electronics
are protected as well as operational during
surge activity.
Enhanced SPDs (SPD* within IEC/BS EN series)
have lower (better) let-through voltage or
protection levels (UP) and therefore further reduce
the risk of injury to living beings, physical damage
and failure of internal electronic systems.
Enhanced Type 1 mains SPDs (for a 230/400 V
system) should have a protection level UP of no
more than 1600 V whilst Type 2 and Type 3 mains
SPDs should have a protection level UP of no more
than 600 V in all modes when tested in
accordance with IEC/BS EN series. Enhanced
signal/telecom SPDs should typically have a
protection level UP no more than twice the peak
operating voltage of the protected system.