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If you look at it from that point of view,
the choice is probably easy and, most
likely, you will be looking for one of those "surge
protectors" - or some device with a similar name
to do the same job, as explained next.
__________________________
Look on page 20 for information about lightning by surfing the Web.


5
¨What’s in a name ?

When you walk in the computer store or electronic supply store, you might ask
for something to protect your appliances against surges, but what to call it ?
The devices that can protect against surges are called "surge-protective
devices" by engineers, but that sounds too
much like jargon to some people.
One name that seems to stick is "surge
suppressor" with a variety of trade-
mark names. The Underwriter's
Laboratories chose to call them
"Transient Voltage Surge
Suppressor" and you might find
that name or the TVSS acronym
next to the listing on the product.
Always make sure that the product
has been tested by a product safety testing organization, such as UL, ETL, or
CSA, as indicated by their labels, as shown here:


You cannot really suppress a surge
altogether, nor "arrest" it (although your
utility uses devices they call "surge
arresters" to protect their systems). What
these protective devices do is neither
suppress nor arrest a surge, but simply
divert it to ground, where it can do no
harm. So a name that makes sense
would be "surge diverter" but it was not
picked. So, for the rest of this booklet, we
will stick with the more popular "surge
protector" and that's what you want to
ask for when you walk in the store.
Then, when you get to the aisle where the surge protectors are on display, you
will most often find many brands, at different prices, so that the next question
will be "Which should I buy ?" That's a more difficult question to answer
because, while the principles and basic technology for these devices remain
the same, manufacturers come up with variations and improvements in
their packages and trade names. So, instead, there are some points to
look for on the packages that will steer you in the right direction.

HOLD IT !
Before you run to the store and buy the most expensive surge protector -
under the assumption that more money automatically gets you a better
protection - look at your personal situation. Asking yourself some simple
questions will help to decide how much surge protection you really need.



6
¨
Decisions, decisions ....

Surge protectors come in many shapes and forms for many purposes, not just
the plug-in kind that you find in the electronic stores. There are several ways
to install them on your power supply: plug and play, do-it-yourself, hire a
licensed electrician to do it, or even call on your power company to do it.
Here is a run down on your options, and who does it:

¨ Purchase one or more plug-in surge protectors
¨ Install a surge protector at the service entrance panel
¨ Have the power company install a surge protector next to the meter

Plug-in surge protectors
This is the easiest solution, and there is a wide variety of brands available in
the stores (as we noted at the start of this booklet, we are not going to
recommend brands). These come in two forms: a box that plugs directly
into a wall receptacle, or a strip with a power cord and multiple outlets.
Depending on the appliance, you will look for a simple AC power plug-in,
or a more complex combined protector for AC power and telephone or
cable - more on that later. However, before you purchase the right
protector for the job, you should think about some details.

There is another decision to make, concerning how a surge protector will
power your appliance if the protective element should fail under extreme
cases of exposure to a large surge or large swell. Most surge protectors are
provided internally with some kind of fuse that will disconnect in case of
failure. However, this disconnect can operate in two different ways,
depending on the design of the surge protector: some will completely
cut-off the output power, others will disconnect the failed element but
maintain the power output.

Quit and be protected or continue ?
For you, it is a matter of choice: would you want to maintain the output power
to your appliance - but with no more surge protection ? Or would you rather
maintain protection for sure - by having the circuit of the protector cut off the
power supply to your appliance, if the protective function were to fail ?
To make an intelligent decision, you must know which of the two
possibilities are designed into the surge protector that you will be
looking for.

What are the lights telling you ?
To help the consumer know what is going on inside the surge protector, many
manufacturers provide some form of indication, generally by one or more
pilot lights on the device. Unfortunately, these indications are not
standardized, and the meaning might be confusing, between one, two -
even three or four lights - where it is not always clear what their color
means. Read the instructions !


7
¨More decisions ...

So far, we have looked mostly at the plug-in surge protectors because they
are the easiest to install and they do not require the services of an
electrician. The two other possible locations for surge protectors are the
service panel (breaker panel) and the meter socket.

Service-panel surge protectors
Instead of using several plug-in protectors - one for each sensitive appliance
is sometimes recommended - you can install a protector at the service
panel of the house (also called "service entrance" or "breaker box").
The idea is that with one device, all appliances in the house can be
protected, perhaps with a few plug-in protectors next to the most
sensitive appliances. There are two types of devices available:
incorporated in the panel, or outside the panel.

Some breaker panel manufacturers also offer a snap-in surge protector, taking
the space of two breakers (assuming that there are blank spaces available
on the panel), and easily installed by the home owner or by an electrician.
However, there are two limitations or conditions to that approach:
(1) The snap-in protectors generally fit only in a breaker panel from
the same manufacturer - possibly down to the model or vintage of
the panel.
(2) To install the snap-in protector, you must remove the front panel (do turn
off the main breaker before you do that !). Most cities have codes allowing
the home owner to do it, under some conditions. Check with your local
authorities to find out if they allow you to do that, or hire a licensed
electrician to do the installation for you.

There are other surge protectors packaged for wiring into the service panel,
either within or next to the panel. That kind of installation is best left to a
licensed electrician (as shown on page 19).

At the meter socket
There might be a possibility that the power
company in your area offers, as an option, to
install a surge protector with a special adapter,
fitting it between the meter and its socket (the
dark band in the bubble of the picture). But
that type of device and installation is out of the
question as a do-it-yourself project, and will
require cooperation from the power company,
if they do offer the program.

Other types of outdoor surge protectors can be
installed near the meter. That kind of installation
must be done by a licensed electrician.


8
¨
Check list ...


Before you decide which way you want to protect your appliances, there are
other points to consider - perhaps this is a good time to make a check list.
We have already mentioned the variation in lightning activity across the
country: Florida is known for very high lightning activity, the West Coast
for much lower (but not zero) activity. For a given area of the country,
the type of your dwelling, and what kind of appliances are to be
protected will influence which type of surge protectors you will be
looking for.

Where do you live ?
This is an important question because the type of dwelling has some
effect on how severe your surge problem might be. In a somewhat
simplified way, consider three categories according to the
arrangement of the utilities:

¨ Detached house with power and telephone
and/or cable TV drops at opposite ends of
the house - the worst possible arrangement
of all. But do not fret, there is a way of
compensating, even after the fact, for this
unfortunate situation, as we will see.

¨ Detached house with all services (power,
cable TV, phone) entering on the same side
of the house. You can improve that situation
further, as shown at the end of this booklet.

¨ Townhouse or apartment building with
services entering the building at one point
and fanned out to the different dwellings -
about the same as the case of the detached
house with all services on the same side.

The first of these three arrangements has often been found to be made
worse by a violation (not intentional) of the prescriptions of the National
Electrical Code that require that the two incoming services be properly
bonded by a grounding conductor. Without going into fine details, the
problem arises because typically the power company and the
communications utilities do their own thing without enough
coordination. Statistics of insurance companies show that one
of the most frequent damage claims is for video equipment. A
possible explanation is the uncoordinated grounding of the
service connections by one of the utilities.




9
¨What appliances are you using ?

From the surge protection point of view, there are four kinds of appliances,
with examples listed below by order of increasing sensitivity to surges,
either because of their nature or because of their exposure:

¨ Motor-driven and heating appliances
Washers (dish and clothes), food processors, power tools, heating and
ventilation motors, pumps, etc.
Water heaters, space heaters, toasters, incandescent light bulbs
¨ Free-standing electronic appliances
Computers without modem, table radios, TV sets with rabbit ears
Compact fluorescent and modern tube-type fluorescent lamps
¨ Communications-connected appliances
Computers with modem, TV with cable or satellite antenna
Fax machines, telephone answering/recording machines
¨ Signal systems
Intruder alarms, garage-door openers, sprinklers, intercom

Let's then take a quick look at each of these and see which might need some
form of surge protection.

Motor-driven appliances and heating appliances
For each of these two categories, there can be two or more kinds, depending on
the type of control used.
¨ Mechanical control (ON-OFF switch, rotary control, etc.), no sophisticated key
pad or other electronic control
¨ Electronic control (programmable operation, key pad, display, etc.)

Appliances with mechanical controls are generally insensitive to surges and
can be expected to withstand the typical surges that occur in a residence.
Extreme cases, such as a direct lightning strike to the building, or one
to the utility, very close, might cause damage.

Appliances with electronic controls can be more susceptible to damage than
those with mechanical controls. Less traumatic but annoying can be upset
memory in programmable appliances, although progress is being made
in providing more built-in protection.

Another difference to be noted is that of appliances permanently connected,
as opposed to those in intermittent use. The risk of a damaging surge
happening at the time of intermittent use is much smaller than that of an
appliance which is on all the time.




10
¨
What kind of appliances ?

Electronic appliances
As soon as the word "electronic" is mentioned, your friends will tell war
stories of surge damage that can raise justifiable concerns. But fear
not; simple precautions and proper protective devices can go a long
way to avoid problems and replace those concerns by
confidence.

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