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Transcript
D:\234830977.doc
Issue No.16
June 2003
HANDY HINTS
FOR
SCHOOL ADMINISTRATORS
CHURCHWARDENS AND
PARISH COUNCILLORS
(Protecting your Assets)
(From the Board of Management of the Diocesan Insurance Fund)
Key Security
There is a condition of your insurance that your property is secured to the best of your
ability. This means that in regards to keys and especially to master keys that they should
be secured at all times and not left locked in cars or desk draws etc. Could you please
ensure that this information is conveyed to all key holders so as careless practices do not
jeopardise a claim pay-out where keys are stolen and there is a reasonable suspicion that
they know the buildings to which they belong. It goes without saying that keys should not
be tagged with an identifier so that a thief can easily go to the building location for illegal
use.
The Board appreciates your diligence in this matter.
Lightning Protection
A longer version of this article appeared in the September 2001 issue of “Handy Hints”, and due to
the fact we are continuing to receive claims for lightning damage, it is included again in short form
for your attention and appropriate action. Whether you be a small Parish with just a facsimile
machine, computer and an answering machine or a school with telephone, security and computing
systems, it is important to protect this equipment as set out below. The Board seeks all your
assistance in installing protection devices, and also it is very important to do so if you have had
previous lightning damage claims or are in an area prone to lightning strikes.
Why bother with lightning protection, doesn't our insurance pay for any damage?
The cost to recover from losses caused by lightning can be very high. In addition to repair of
actual damage to electrical or electronic equipment, there are other costs such as loss of data
held on computer, delays whilst staff cannot use their computers, make or receive phone calls,
send or receive faxes etc.
These losses are not always covered by insurance and the inconvenience, stress and long hours
to co-ordinate repairs and catch up, are almost certainly excluded.
One of our schools had a recent claim where a lightning induced surge current entered through
both phone lines and power supply causing extensive damage.
The extent and cost (excluding GST) of the damage was:-
1
Damage to switch units $17,000
Damage to Computer equipment $6,500
Damage to Fire Alarm power supply $1,000
Damage to Alarm System $1,800
Miscellaneous Costs $2,000
Total labour cost for repairs and installation $6,000
The total claim was almost $40,000
The total time taken to settle this claim from the incident date was 6 months. You can see that the
inconvenience and disruption was great.
It is therefore in everyone's interest to identify cost effective ways to reduce the incidence and
severity of lightning damage.
How does lightning cause damage to electrical and electronic equipment?
When lightning strikes the ground or a structure, it causes the voltage at that point to rise
dramatically, causing electrical current to flow from the that point to points further away from the
strike.
If lightning strikes a structure or the ground close-by and that structure has electrical cabling
connecting it to another structure further away, the increase in voltage at the point where the
lightning strikes, will cause current to flow along the cable. This can cause damage to equipment at
both ends of the cable.
A lightning strike also creates electrostatic and electromagnetic fields which can induce currents in
exposed cables, again causing damage to equipment at both ends of the cable.
How do we reduce the effects of a lightning strike on electrical and electronic equipment?
One of the major suppliers of lightning suppression equipment suggests the following steps:1. Protect Power Lines
The most common source of damage to electrical and electronic equipment as a result of a
lightning strike is the power supply. A surge or spike entering the incoming power lines has
the potential to damage every electrical and electronic item connected to those power lines.
The first and most important stage of protection is a surge diverter located inside the
main electrical switchboard. Surge diverters direct to earth most of the energy of a surge
or spike at the point of entry to a building or major power distribution point. Surge diverters
typically cost around $500.00 plus installation.
Whilst a surge diverter can substantially reduce spikes entering electrical and electronic
equipment, considerable damage can still be done to voltage sensitive equipment and it is
therefore necessary to also install a surge filter for each item of sensitive equipment. Surge
filters can either be installed in power distribution boards or can be free-standing with a
flexible lead for plugging into a standard general purpose power outlet.
Free standing surge filters typically cost around $250.00 and those installed in a distribution
board around $300.00 and will reduce surges down to 240 volt per phase, which is the
standard operating voltage in Australia for electrical and electronic equipment. A surge filter
located in a distribution board can provide filtering and is therefore a lot more cost effective
to all devices connected to that power circuit (eg. several computers).
2
2. Protect Signal/Data Lines
Protection of power lines does not prevent surges entering electronic equipment along
signal and data cables. Even with power line protection, damage to computer networks can
be extensive if a surge enters data cabling connecting a number of computers together. A
surge can also enter a computer through a telephone line if the computer is connected to a
modem. It is therefore also necessary to protect against damage to electronic equipment
from this source.
Surges can also enter telephone networks via incoming telephone lines and there is a range
of protection devices that can be mounted inside telephone main distribution frames.
As a voltage surge can occur at either end of a signal or data cable causing electrical
current to flow in either direction, it is necessary to protect electronic equipment at both
ends of the cable.
Costs vary depending on the signal and cable type, however, to protect ten incoming
telephone lines with protectors mounted inside the main distribution frame, a typical cost is
around $200.00 and for a computer it costs around $100.00 for network connection
protection and $80.00 for modem connection protection.
Conclusion
Damage from all but the most intense lightning strikes can be eliminated by the adequate
protection of power, signal and data cabling. It is therefore within your power to prevent the stress
and sleepless nights when trying to return to normality after a lightning strike takes out your
computer systems, telephone system, burglar alarm, access control system, fire detection system
and facsimile machine.
Who do I go to for assistance?
The following two companies supply a full range of lightning protection equipment and can provide
advice and prices:SCA Distributors Pty Ltd, 178 Wecker Road, MANSFIELD QLD 4122
Telephone: (07) 3849 5077
Facsimile:
(07) 3849 7035
No Virus Technologies Pty Ltd Agents:
Queensland PowerCom (Qld) Pty Ltd
Telephone:
3
(07) 3851 3144