fftt wrote:
On Sep 17, 4:16 am, "HeyBub" wrote:
RBM wrote:

If you've never had a problem with line lightning, I wouldn't bother.
I don't believe that the type of surge protectors you are referring
to would do much to protect sensitive electronics anyway. If you want
them to protect things like well pumps and motors, fine, but the
typical lightning strike that causes a surge, won't be stopped
quickly enough or completely, to safeguard sensitive electronics, and
won't help at all if your underground dog wire gets hit again
You're spot on - if the lightning hits your house. If, however, the
lightning strike is merely near your home, a whole-house surge protector
(WHSP) will help.

As for "quickly enough," reputable WHSPs are rated from "instantaneous" to
five nanoseconds. Top-line WHSPs (Leviton, Intermatic, Square-D, etc.), can
handle surges up to 180,000 amps and provide up to $25,000 damage
reimbursement for connected equipment loss.

The protection in virtually all suppressors, service panel and plug-in,
uses MOVs. They are fast enough for any surge on incoming utilities.
Five nanoseconds is faster than the surge rise time (which I believe is
what Bub said).

Some WHSPs come with attachments to protect CATV and telephone lines.

Do oyu have a recommnedation for a WHSP?

Preferably Square-D (I have used their panels & breakers for the past
30 years with good results)

I had an electrical "event" (not lightening related) last November
that ruined a couple TV's, DVD players, AC adpaters, transformers,
garage door openers, etc.
SoCal Edison wound up paying for all of them but it was a hassle to
buy & replace all the stuff......so I would prefer to avoid

Depending on what the "event" was, "whole house" and plug-in suppressors
may not provide protection. In particular "crossed" power lines.

My meter is outside along with a main breaker. The service panel is
in a down stairs laundry room.
Where should the WHSP be installed?

Where is the connection to the earthing electrode(s). It is probably at
the outside disconnect. That is where the service panel suppressor
should be connected. You need the suppressor connected to the earthing
electrode system. That somewhat limits your options. If the service
disconnect is outside, the basement is not a service panel (there should
be separate neutral and ground busses. If installed at the basement
panel (panels?), the suppressor would have to have connections to both
hot busses, the neutral bus and the ground bus. The ground bus would
have to have a good, short connection to the earthing electrode system
(which is unlikely now).

Except for suppressors that are installed on the meter base (by the
utility) virtually all suppressors are downstream from the service breaker.


The best information on surges and surge protection I have seen is at:
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf
- "How to protect your house and its contents from lightning: IEEE guide
for surge protection of equipment connected to AC power and
communication circuits" published by the IEEE in 2005 (the IEEE is the
major organization of electrical and electronic engineers in the US).
And also:
http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the
appliances in your home" published by the US National Institute of
Standards and Technology in 2001

The IEEE guide is aimed at those with some technical background. The
NIST guide is aimed at the unwashed masses.

The other consideration (in both guides), which is often missed, is that
the "ground" wire from the cable and phone entry protectors needs to
make a short connection to the earthing electrode system near the power
service. The IEEE guide says 10 ft is too long. If there is a strong
surge that is earthed in your system, the potential of your house
"ground" may be thousands of volts above "absolute" ground potential.
Much of the protection is that the power and cable and phone wires rise
together. That requires *short* ground wires. Another method is to run
the phone and cable through a special service suppressor, as in Bub's
post. That may not be practical if the suppressor is outside.

The NIST guide, using US insurance information, suggests most damage is
from high voltage between power and cable or phone wires. There is an
example of that in the IEEE guide starting pdf page 40.

Because the most common damage is high voltage between power and cable
or phone wires, a plug-in suppressor at high value equipment with both
power and signal wires may be a good idea. All interconnected equipment
must be connected to the same plug-in suppressor, and all external wires
to a set of equipment (power, phone, cable) must go through the
suppressor. Plug-in suppressors work by limiting the voltage from all
wires to the ground at the suppressor (also illustrated in the example
above).

What you use depends on the risk and the value of what you are protecting.

I agree with others that your dog fence is not protected by a service
panel suppressor. You can have similar problems with a submersible well
pump, but many of the motors include surge suppressors.

--
bud--