Date:
October 2013
POWER SURGE
PROTECTION & REGULATIONS
High Current - High Voltage -
Short Duration Impulses - Power
Surges:
These are all terms to strike fear
into the minds of all electrical
and electronic system designers
and installers. It is time, and more
importantly, it is a requirement to
act to reduce or eliminate these
risks. However, it seems that cost
and competition are significant
factors in ignoring the need
for effective and coordinated
protection.
These rarely seen or often
undetected threats originate
from many sources:
An Indirect lightning strike some
There is little we can do to ensure that faults are
not created and certainly nothing to prevent the
randomness and unpredictability of Lightning
strikes.
However, although we cannot eliminate the many
and varied causes, we can certainly reduce their
effects.
Surge Protection Devices (SPD’s) are designed
to specifically protect electrical and electronic
equipment from these spikes and transients. They
can improve reliability, availability, maintainability
and safety, all resulting in the reduction of lost
production time, fewer repairs, together with less
data and information loss, thereby improving
productivity and profitability. The extra cost may
be a fraction more but with a significant reduction
in ongoing expenditure the savings more than
make up for the initial outlay.
CONTENTS:
The Need For Surge
Protection
___________________
SPD Selection Flow
Chart
___________________
PD Devices Launches
NEW LOOK Website
www.pddevices.co.uk
___________________
FREE CPD Training
The Lightning Protection Systems,
where fitted, offer a good
protection provided the earth
bonding is good throughout the
facility. Surge Protection Devices
are a requirement for most
installations.
kilometres away, will be looking
for an easy path to earth, it will
find a route through a building!
A Direct Lightning Strike, where a
portion of the discharge current
into the lightning protection
system or other conductive
materials will attempt to flash
over into the internal installations.
The effect of Electrical Switching
caused by utilities, isolation
arcing, electrical motor cycling
or sudden changes in electrical
flow. These are but a few of
many causes.
The Power Utilities external surge arresters provides
a good primary protection, but long lead length,
installation mistakes and supply variances can
cause a problem to the user that is not necessarily
recognised by the utility. Surge Protection Devices
within the facility are therefore necessary.
Standards and Regulations make
it a clear requirement for Surge
Protection Devices.
Continued on Page 2
PD Devices Ltd. (Power Development) Old Station Yard, South Brent, Devon (UK), TQ10 9AL
Tel: +44 (0) 1364 649248 | Fax: (+44) (0) 1364 649250 | Email: sales@pddevices.co.uk | Web: http://www.pddevices.co.uk
VAT No. 782 1267 25 Registered in England No. 4253515 – Registered Office: Francis Clark, Sigma House, Oak View Close, Edginswell Park, Torquay, TQ2 7FF, UK
© PD Devices Ltd 2013.
Fun Facts & Information
Did you know there are bolts of lightning striking
somewhere on Earth every second.
The study of lightning is known as fulminology.
BS 7671:2008 IET
Wiring Regulations
Seventeenth Edition
Section 443 defines the need
for Surge Protection Devices
and the suggested coordinated
approach.
Section 534 defines the devices
for the protection against
overvoltage
BS EN 62305 series
of Standards Defines
the Protection
against Lightning
Surge Protection
Device Coordination
BS 7671 and BS EN 62305 require
the coordination of SPD, where
the latter standard considers the
installation of the correct device
to limit the transient overvoltages
at the appropriate location
within the building. To facilitate
this, the building is partitioned
by areas or zones (Lightning
Protection Zones) for which the
SPD with the recommended
overvoltage suppression is
intended for installation. The
zones are based on the degree
of risk and to provide a method
to ensure the protection of the
equipment.
SPD Selection
(For SPD Selection Flow Chart CLICK HERE)
SPD’s should be fitted in the main distribution
board and as close to the service entrance as
possible.
If there is a Structural Lightning Protection System
(LPS) installed (or a overhead mains supply) a
Type 1 device is should be fitted, typical to a PD
Devices T1SP3/25/100/230 for critical buildings –
Hospitals, Schools etc. For less critical buildings a
T1SP3/12.5/50/230 would be recommended. Single
phase versions are available.
Without a structural LPS fitted and underground
mains supply feed, a Type 2 device is fitted similar
to the PD Devices DSP Series or SPM series. The
T1SP series devices would also offer the same
levels of protection.
Critical Equipment - It is advisable to install Type
Part 1 – General Principles for the Zone LPZ 0 is outside the structure 3 devices to ensure the protection level is kept
Protection of structures against
Lightning
Part 2 – Risk Management
Part 3 – Physical damage to
structures and life hazard
Part 4 – Electrical and electronic
systems within structures
BS EN 61643-11 – Requirements
and tests for Low Voltage Surge
Protection Devices connected
to low voltage power distribution
systems.
of the building and is subject to
the severest threat of lightning
currents and electrical fields.
Zone LPZ 1 is the first zone within
the building and is prone to the
induced fields and flashover into
the building.
Zone LPZ 2 is the second zone
within the building where the
risk to electrical equipment is still
high.
Antenna
LP
L
PZ 0
LPZ
Continued on Page 3
Why not Download our Product Information
Brochure CLICK HERE
Maasstt or
M
Mast
or Railing
Railliin
ng
g
Electrical Power Line
LPZ 2
LPZ
Boundary
of
LPZ 1 (LPS)
Equipment
Critical
Equipment
BS EN 61643-22 – Selection and
application for Low Voltage
Surge Protection Devices
connected Telecommunications
and signalling networks.
be protected by additional devices similar to the
PD Devices TLP and DBP ranges.
CLICK IMAGE to see our products
or visit www.pddevices.co.uk
application for Low Voltage
Surge Protection Devices
connected to low voltage
power distribution systems.
and tests for Low Voltage Surge
Protection Devices connected
Telecommunications and
signalling networks.
Telecommunication and Data Equipment should
Zone LPZ 3 is the third and
subsequent areas of diminishing
risk to the equipment.
BS EN 61643-12 – Selection and
BS EN 61643-21 – Requirements
to below the recommended 1500 volt. The PD
Devices DSP series being Type 2 and 3 can be
fitted here. In cases where the protection needs
to be at the equipment itself, then devices similar
to the PD Devices MBP type of products are
advisable.
Equipment
Telecommunication Line
Water Pipe
Gas Pipe
SPD 0/1 - Lightning Current Protection
SPD 1/2 - Overvoltage Protection
PD Devices Ltd. (Power Development) Old Station Yard, South Brent, Devon (UK), TQ10 9AL
Tel: +44 (0) 1364 649248 | Fax: (+44) (0) 1364 649250 | Email: sales@pddevices.co.uk | Web: http://www.pddevices.co.uk
VAT No. 782 1267 25 Registered in England No. 4253515 – Registered Office: Francis Clark, Sigma House, Oak View Close, Edginswell Park, Torquay, TQ2 7FF, UK
© PD Devices Ltd 2013.
Fun Facts & Information
Grand Canyon National Park alone averages more
than 26,000 lightning strikes per year.
Astraphobia is the fear of thunder and lightning.
The panel is the best place for
surge protection.
When dealing with transient
overvoltages, there are many
reasons why the panel is the best
location for surge protection:
•Multiple circuits can be
protected by one device, rather
than the multiple ‘at equipment’
devices that would otherwise be
required.
•Limits the electromagnetic
propagation of the overvoltage.
Surge protection in the panel
limits the inductive coupling to
other conductors by minimising
the size of the conducting ‘loop’
(e.g. phase to earth) during an
overvoltage event.
•Lead lengths can be controlled
and kept to a minimum; loops
can be eliminated.
PD DEVICES LAUNCHES
NEW WEBSITE
CLICK IMAGE to see our NEW LOOK Website
or visit www.pddevices.co.uk
•Ensures a good coordinated
approach
PD Devices are a UK based,
in-house manufacturer of
Surge Protection Devices,
offering a full range of products
including the key Metal Oxide
Varistor element. This allows
full customisation at standard
product pricing.
Article written by Mike Rendell
Managing Director of PD Devices Ltd
CLICK IMAGE to see our
NEW Video Page or visit
www.pddevices.co.uk
•Electrically ‘noisy’ equipment
is usually supplied by its own ring
or spur, so a surge protection
device in the panel is effectively
between the ‘noisy’ source and
the equipment that requires
protection.
•Maintenance and monitoring
of the surge protection is
centralised and simplified, as
many panel products have
options for automatic monitoring
and pre-failure warning.
•As panels are normally located
at the entrance to an installation
or area, the installation of surge
protection at the panel fits well
with the Lightning Protection
Zone concept of BS EN 62305.
Image shows the SPD Selection Flow Chart
Available on our NEW improved website
www.pddevices.co.uk
For All Your Surge Solutions contact us
using our online form CLICK HERE
FREE CPD presentations can be arranged that will
explain the requirements of current standards and the
approach to effecting appropriate solutions.
Is published by: PD Devices Ltd
Old Station Yard, South Brent
Tel: +44 (0) 1364 649248
Fax: +44 (0) 1364 649250
Web Site: www.pddevices.co.uk
© PD Devices Ltd 2013
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Training Call: (0) 1364 646131
PD Devices Ltd. (Power Development) Old Station Yard, South Brent, Devon (UK), TQ10 9AL
Tel: +44 (0) 1364 649248 | Fax: (+44) (0) 1364 649250 | Email: sales@pddevices.co.uk | Web: http://www.pddevices.co.uk
VAT No. 782 1267 25 Registered in England No. 4253515 – Registered Office: Francis Clark, Sigma House, Oak View Close, Edginswell Park, Torquay, TQ2 7FF, UK
© PD Devices Ltd 2013.