Can a battery do surge protection?

[David Askari]

If my device was hooked up to an AC outlet with a PWR adapter that
charged the battery while the device drew power from the battery.
Would it be protected from surges like those APS units?

 

[Sofie]

Not necessarily..... the answer absolutely depends on the specific and
actual circuitry of the PWR adapter or charger.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


"David Askari" <davidlaska@aol.com> wrote in message
news:e42406d1.0404071209.e1a15c5@posting.google.com...

If my device was hooked up to an AC outlet with a PWR adapter that
charged the battery while the device drew power from the battery.
Would it be protected from surges like those APS units?

 

[David Askari]

"Sofie" <sofie@olypen.com> wrote in message news:<10790il49vc6906@corp.supernews.com>...

Not necessarily..... the answer absolutely depends on the specific and
actual circuitry of the PWR adapter or charger.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
plus I thought more and if the battery is full or charged, it won,t be

taking much then.

 

[w_tom]

Let's assume the destructive transient is differential
mode. That means the transient 'pushes' on one wire and
'pulls' on the other. If those wires are shorted together
either by battery or by a shunt wire, then that transient is
short circuited - does not continue on through into
electronics. BTW, from first year circuits, the battery
appears as a short circuit or shunt wire to that transient.
Battery acts as a short circuit to transient.

Destructive transients are common mode. That means the
transient is 'pushing' down one or all wires. If the same
transient is on all wires, then battery or shunt wire sees no
voltage difference. To that battery, no transient exist
because there is no voltage difference. In the meantime, that
common mode transient procedes on, destructively, through
electronics. Battery has provides no effective protection.

Therein lies a major problem with 'so called' protection
such as the APC plug-in UPS. They don't even claim protection
from the destuctive common mode transient. Read their
specifications. But even worse, a plug-in APC (or on-line
battery) can even provide the transients with more destructive
paths through that electronics.

Effective protection means earth ground. No way around the
concept. To avoid common mode damage, the transient must be
earthed before it can enter the building. To hype what is
really ineffective protection, manufacturers such as APC
simply forget to mention earthing. No earth ground means no
effective protection. Better to not tell the whole truth
since that might only hurt their sales.

Bottom line answer: battery is not effective protection
from the typically destructive (common mode) transient. For
such protection, get (or make) a 'whole house' protector.
Verify that the essential earth ground is intact, meets post
1990 National Electrical Code, and is sufficient.

David Askari wrote:

If my device was hooked up to an AC outlet with a PWR adapter that
charged the battery while the device drew power from the battery.
Would it be protected from surges like those APS units?

 

[David Askari]

Bottom line answer: battery is not effective protection
from the typically destructive (common mode) transient. For
such protection, get (or make) a 'whole house' protector.
Verify that the essential earth ground is intact, meets post
1990 National Electrical Code, and is sufficient.

Are new residential construction required to meet the standards
mentioned, or only a few states requir it. It whole house grounding
you mentioned is the 3 receptical plug with the third wire running to
a (copper?) post 4 or more feet in the earth? If yes , then in a old
house with no third wire, can you run your,s to such a post one has
inserted in the earth?

 

[David Askari]

davidlaska@aol.com (David Askari) wrote in message news:<e42406d1.0404081507.242fde29@posting.google.com>...

Bottom line answer: battery is not effective protection
from the typically destructive (common mode) transient. For
such protection, get (or make) a 'whole house' protector.
Verify that the essential earth ground is intact, meets post
1990 National Electrical Code, and is sufficient.

Are new residential construction required to meet the standards
mentioned, or only a few states requir it. It whole house grounding

I read your post again and understand the grounding is done nationally
since the 90,s

 

[exray]

David Askari wrote:

I read your post again and understand the grounding is done nationally
since the 90,s

Gounding has been done nationally since 'forever'. The mandated nuances
change about every 5 years or so since back in the 1920s but the concept
is the same. The goal is to get all electrical devices, or things like
ductwork that could be potentially electrified via faults, to a common
grounding point.
Poking a ground rod here for cable tv and there for phone and somewhere
else for power has proven to be unacceptable because of the voltage
potential between them. Someone sticks the cable TV wire in their mouth
while opening the frige for another beer and sues the power company
because they got zapped and BINGO, a new rule is created.
Yes, I'm straying from the point of the original post but your last
response made it seem like grounding was a new thing only invented in
the 90s.

-Bill M

 

[w_tom]

Grounding was always required. However grounding for
transient protection means distance to ground is also
critical. The other post were first two previous discussions
that describe general concepts. Third discussion listed below
ground gets more into technical details:
"Power Surge" on 29 Sept 2003 in the newsgroup
alt.comp.hardware or
http://tinyurl.com/p1rk

Fourth discussion in newsgroup misc.rural is engineers
discussion the science of earthing:
Storm and Lightning damage in the country 28 Jul 2002
Lightning Nightmares!! 10 Aug 2002
http://tinyurl.com/ghgv and http://tinyurl.com/ghgm

Earthing is performed to solve two different problems -
human safety and transistor safety.

David Askari wrote:

I read your post again and understand the grounding is done
nationally since the 90,s

 

[David Askari]

exray <dontspamme-exray@coqui.net> wrote in message news:<107chh5aten01f0@corp.supernews.com>...

David Askari wrote:


I read your post again and understand the grounding is done nationally
since the 90,s

Gounding has been done nationally since 'forever'. The mandated nuances
change about every 5 years or so since back in the 1920s but the concept
is the same. The goal is to get all electrical devices, or things like
ductwork that could be potentially electrified via faults, to a common
grounding point.
Poking a ground rod here for cable tv and there for phone and somewhere
else for power has proven to be unacceptable because of the voltage
potential between them. Someone sticks the cable TV wire in their mouth
while opening the frige for another beer and sues the power company
because they got zapped and BINGO, a new rule is created.
Yes, I'm straying from the point of the original post but your last
response made it seem like grounding was a new thing only invented in
the 90s.

-Bill M

I trying to find if grounding is a complex thing or a rod that is in
the earth four feet with all the grounding wires claped to it. The
90 was in reference to newer laws

 

[David Askari]

w_tom <w_tom1@hotmail.com> wrote in message news:<4076D91B.FCC83A37@hotmail.com>...

No construction is required to build as if the transistor
exists. However post 1990 National Electrical Code makes some
requirements that are also essential to transistor protection.

Third prong in receptacle is safety ground. Although many
grounds may be interconnected, each ground is electrically
different. For example computer motherboard ground is
different from chassis ground is different from receptacle
ground is different from breaker box ground is different from
earth ground. All are interconnected. But, for example,
would you cannot a lightning rod to the motherboard ground?

What matters is which ground earths an incoming transient.
That must be a single point earth ground. Earth ground (and
not the protector) is the protection. Earth ground is THE one
essential component in every protection system. (Notice that
plug-in protectors avoid all discussion about earthing).

What does lightning seek? Earth ground. It may find a path
to earth, destructively, via your computer. However if that
incoming utility wire is earthed before entering a building,
then no interior appliance damage. No reason for lightning to
find a destructive path to earth via your computer.

Some wires such as CATV are hardwired directly and 'less
than 10 feet' to this single point ground. Others would not
provide utility service if always earthed. AC mains and
telephone wires are then earthed only during the transient -
by a 'whole house' protector. IOW the protector only connects
AC electric and telephone wires to earth during the transient.

AC wall receptacle cannot accomplish this for just too many
reasons. These and other concepts discussed previously in
"RJ-11 line protection?" on 31 Dec 2003 in pdx.computing, or
http://tinyurl.com/2hl53 and in "Opinions on Surge
Protectors?" on 7 Jul 2003 in the newsgroup
alt.certification.a-plus or
http://tinyurl.com/l3m9

CATV and satellite dish need no protector since each must be
hardwired directly to protection - earth ground. 'Whole
house' protector is so inexpensive and so effective that your
telco installs same, for free, in your premise interface box.
Therefore that telco interface box must also connect to same
earth ground as AC electric.

Transients on AC electric are your problem. You must
install the AC electric 'whole house' protector so that a
connection from each AC electric wire from breaker box and to
earth ground is less than 10 feet. One minimally acceptable
version (rated at least 1000 joules and 50,000 amps) is sold
in Home Depot as Intermatic EG240RC or IG1240RC (for less than
$50). Many others are available. This provides both common
and differential mode protection.

As should be obvious in those other discussions, every
incoming utility must make a less than 10 foot connection to
the same single point ground - for effective transistor
protection. National Electrical Code only addresses human
protection. IOW you must exceed NEC requirements to protect
transistors - such as ones that control the furnace or GFCI
bathroom receptacles.


I am going to visit the links and lighting stikes are real even here

were thunderstorm are only onece a year, I saw a lightning strike less
than a few hundred yards from my house and had to recover my hard
drive.

Is this earth grounding for transistors simple to install for a laptop
and destop? I now realize it is more than the human protection
grounding (hence the third wire for screwups in wiring)

 

[w_tom]

To understand transistor protection, draw the picture to
include house, little computer inside house, earth, and cloud.
Some take a myopic perspective of computer in a room - then
try to solve problem with a plug-in protector adjacent to
computer. Your picture - your perspective - must be an
electrical circuit that connects cloud, through house, to
earth ground. Does that path go through computer?

Minimally acceptable earth ground must be a copper clad rod
at least eight feet into earth. A major improvement in
protection. Rod must go well below frost line. A four foot
rod is far less effective and is even in violation of National
Electrical Code (NEC). If underlying earth is more
conductive deeper in earth, then earthing connection may, in
rare cases, need be even deeper. In the Perennes of Europe,
they had to earth 150 feet to get down below glacier rumble.

Example: a FL house was struck repeatedly on bathroom wall.
They installed air terminals connected to eight foot ground
rods. Lightning struck that bathroom wall again. Why?
Bathroom plumbing made a better connection to more conductive
limestone. Air terminal ground rods were only in sand.
Lightning found a better path into limestone. Again,
protection is only as effective as its earth ground as was
explained previously in that discussion in misc.rural.

Some towns even in regions of few transients, instead, suffer
from many direct strikes. Geology beneath a building is
another factor. Neighborhood history must be considered when
estimating whether to install more than one eight foot ground
rod. If installing many rods, then code even defines how they
must be spaced.

For most locations, an eight foot ground rod is sufficient -
a major improvement when building ground is upgraded to meet
post 1990 NEC requirements. But if your building requires
high reliability, then Ufer grounding or halo loops are a
defacto necessity. Massive increase in the grounding network
for a minor increase in earthing effectiveness.

Earthing costs so little when home is constructed. Costs so
much when builder could not be bothered. Unfortunately we
still build homes as if the transistor did not exist. Some
electricians even cut a ground rod in half to ground two
buildings with one rod - having no idea why that earth ground
is so important.


David Askari wrote:

I am going to visit the links and lighting stikes are real even here
were thunderstorm are only onece a year, I saw a lightning strike less
than a few hundred yards from my house and had to recover my hard
drive.

Is this earth grounding for transistors simple to install for a laptop
and destop? I now realize it is more than the human protection
grounding (hence the third wire for screwups in wiring)