Surge protectors to use with home electronics when grounding is notavailable?

[[email protected]]

I am moving into a home which was built in the late 1800s where
brownouts are common and no grounds are available on the outlets. I
will not have the option of rewiring the home.

Does anyone have suggestions as to how I can best protect my home
electronics (computers, entertainment center, etc).

I've seen plenty of "surge protectors" which look like they are more
marketing hype than anything else. What are your opinions on these?

Has anyone heard of cases where people actually cashed in on the
insurances offered by these devices ? How about cases of renter's
insurance covering damage due to electrical problems during storms (or
other timers) ?

If there are surge suppressors out there that are worth their salt,
are any of the insurances valid when the suppressors are not connected
to grounded outlets?

Thanks for any assistance.

 

[Sjouke Burry]

I am moving into a home which was built in the late 1800s where
brownouts are common and no grounds are available on the outlets. I
will not have the option of rewiring the home.

If you are not allowed to rewire, then shut off the power,
and buy oil lamps etc, to return to the year 1900
Using unreliable wiring, is like playing russian roulette.
You can die from it.

 

[JeffM]

I've seen plenty of "surge protectors"

Wasn't this discussed here about a week ago?
Why, yes. It was.
http://groups.google.com/groups/search?q=surge+ingroup:sci.electronics.basics&scoring=d
(Too lazy to even scan thru a few days' worth of posts before posting
as well.)

 

[ehsjr]

I am moving into a home which was built in the late 1800s where
brownouts are common and no grounds are available on the outlets. I
will not have the option of rewiring the home.

Does anyone have suggestions as to how I can best protect my home
electronics (computers, entertainment center, etc).

Throw "best" out the window.
Some things you can do: use fiber optic telephone and television
service.

I don't think insurance will be honored when there is no ground,
but I don't know for sure. Same thing for the warrantees on
point of use protectors.

I've seen plenty of "surge protectors" which look like they are more
marketing hype than anything else. What are your opinions on these?

IEEE recommends point of use protectors in conjunction with
whole house protection, so at least some point of use protectors
are good. But you can't follow the IEEE recommendation, which is
why you have to throw "best" out the window. Without ground,
you _cannot_ correctly assume that your equipment is protected
from surges, unless it is completely disconnected from places
where the surges can get in - mains, tv leadin, telephone
wires etc.

Ed

 

[bud--]

Throw "best" out the window.
Some things you can do: use fiber optic telephone and television
service.

I don't think insurance will be honored when there is no ground,
but I don't know for sure. Same thing for the warrantees on
point of use protectors.



IEEE recommends point of use protectors in conjunction with
whole house protection, so at least some point of use protectors
are good. But you can't follow the IEEE recommendation, which is
why you have to throw "best" out the window. Without ground,
you _cannot_ correctly assume that your equipment is protected
from surges, unless it is completely disconnected from places
where the surges can get in - mains, tv leadin, telephone
wires etc.

..
I agree with all of that.

Add a ground to a few receptacles?

Most commonly damaged equipment has connections to both power and signal
(phone, cable) wires.

Wireless router for computer phone? The router is at risk, but the
computer does not connect to both power and phone wires.

Add a service panel suppressor? Not obvious if that is an option.

Phone and cable entry protectors should connect with a short 'ground'
wire to the earthing wire at the power service. A lot of surge
protection is keeping the power/phone/cable wires at about the same
voltage (even though that voltage may wind up thousands of volts above
'absolute' ground for an instant). That requires a short wire.

Check that the power service is connected to an earthing electrode.
Probably the water pipe if the water service has at least 10 ft metal in
the ground. Maybe a ground rod.

Plug-in suppressors can provide protection but can shift the ground
potential at the suppressor. Without a power 'ground' wire that can be a
problem. All interconnected equipment needs to connect to the same
suppressor. External wires, like cable and phone, also have to go
through the suppressor. I would be nervous running cable and phone wires
through a suppressor that does not have a power ground.

Equipment connected through a 'wall wart' is generally fairly well
protected.

All of this is surge protection and provides no protection from brownouts.

 

[neon]

a surge protection usualy only protect what is comming trough the power line. it will not protect you if your house is striked by lighting

 

[[email protected]]

Keep your equipment in a different place. Do you have the option of
building a shop on the property with modern wiring? Tools and equipment
can live there happily, but I believe you should rethink your idea of an
electronic entertainment center, may I suggest some acoustic guitars and
a nice piano, perhaps? Don't fret the oil lamps, lighting will work fine
on line-to-neutral without ground, provided the mice haven't gnawed too
deeply into the insulation.


http://www.zerosurge.com/HTML/purchspec.html

That should answer your questions about suppressor operation. However,
your problem is deeper than a concern about line surges, and as others
have offered, surges and brownouts are not the same thing. Modern
appliances are designed to work with 2/1 wiring, that is, two conductors
and a safety ground. Using these devices without that ground attached,
leads to a plethora of safety and performance concerns.

Since you are choosing to live in an apparently historically protected
domicile, you should probably likewise choose to live in a manner
consistent with the restrictions of said domicile. Welcome to the 19th
century!

Thanks all for the responses.

I see that there isn't much I can do short of having the building
rewired (maybe if I purchase it down the road).

I added brownout and surge protection to my renter's insurance and
knocked the deductible down. I've discussed such policies at length
with several insurance companies and feel that this will be adequate.
If anyone thinks otherwise, please share your comments.

I lived in a home with no grounds while attending college and had no
issues with electronics or computers so I guess I'll just have to wait
and see how things go here. There are more electrical storms in this
area during this time of year, which is my reason for additional
concern.

The place is wired for high speed internet/digital cable and the last
dweller used two A/C units (there are a total of 24 circuits in the
home. Some circuits are 30 A- not sure if that goes for all of them
yet. The presence of 240 VAC for both the stove and an electric dryer
has me wondering if the wiring may be more recent than 1900? It is
not knob and tube wiring but is definitely old. I'll have to get
pictures online after I move in to see what electricians have to say
(provided the said plethora of performance problems doesn't completely
prevent me from accessing the internet).

 

[[email protected]]

I am moving into a home which was built in the late 1800s where
brownouts are common and no grounds are available on the outlets. I
will not have the option of rewiring the home.

Does anyone have suggestions as to how I can best protect my home
electronics (computers, entertainment center, etc).

I've seen plenty of "surge protectors" which look like they are more
marketing hype than anything else. What are your opinions on these?

Has anyone heard of cases where people actually cashed in on the
insurances offered by these devices ? How about cases of renter's
insurance covering damage due to electrical problems during storms (or
other timers) ?

If there are surge suppressors out there that are worth their salt,
are any of the insurances valid when the suppressors are not connected
to grounded outlets?

Thanks for any assistance.

I think I'll add these portable GFCIs to major appliance circuits.
They do not address the electronics I was asking about in this
question but at least they'll add a small degree of safety. I feel
that disturbing the original wiring to install built-in GFCIs would be
more netative than any positives provided from them.

 

[NB]

Wasn't this discussed here about a week ago?
Why, yes.  It was.http://groups.google.com/groups/search?q=surge+ingroup:sci.electronic...
(Too lazy to even scan thru a few days' worth of posts before posting
as well.)

And why hasn't w_tom jumped in yet?

 

[w_tom]

I am moving into a home which was built in the late 1800s where
brownouts are common and no grounds are available on the outlets. I
will not have the option of rewiring the home.

The effective surge protectors work regardless of whether
receptacles have ground. The only relevant ground is a short (ie
'less than 10 foot') ground from protector to earth. Rewiring
interior circuits was never required for surge protection. But that
breaker box earth ground (and earthing for all other incoming
utilities) must be upgraded to post 1990 NEC requirements. In many
cases, that means 'less than 10 feet' of bare 6 AWG copper wire, the
10 foot earth ground rod, and a 'whole house' protector.

Effective protectors work by earthing surges. That wall receptacle
wire is woefully too long, has sharp bends, had splices, is bundled
with other wires, etc. Each point conspires to make it only a safety
ground (equipment ground) and not earth ground.

A properly earthed 'whole house' protector is also the only solution
to protecting GFCIs. Just another in a long list of electronics that
requires a properly earthed 'whole house' protector.


A surge protector works by dissipating surge energy in earth.
However, if a tiny 100 amp surge is grounded by a power strip
protector, then the 50 feet of grounded romex means the protector is
at something less than 12,000 volts. Why such high voltage between
protector and earth? Wire is too long, too many sharp bends, etc.

Install three wire plugs and still have no earth ground? Yes. This
is why only responsible companies sell 'whole house' protectors - ie
Keison, Square D, Cutler-Hammer, Intermatic, Leviton, Siemens, GE,
etc. No protector provides protection. Protection is provided by
earthing. That means wire length must be short, earthing wire must be
separated from all other wires, etc.

How to install that breaker box earth ground. If the 6 AWG goes up
over the foundation and down to the earth rod, then protection has
been compromised. Again, too long, sharp bends, etc. That earthing
wire best goes through foundation and down to the ground rod.
Distance to earth is that critical.

A 'whole house' protector must dissipated lightning energy in earth
- and remain functional. Yes, the effective protector must earth
direct lightning strikes without damage. Then that surge need not
find earth, destructively, via household appliances - two wire or
three.

No protector will stop or absorb what three miles of sky could not.
And yet that is what some plug-in protector promoters are claiming.
All appliances contain protection. Protection that is not overwhelms
if the connection from each incoming utility wire (inside every cable)
to earth is 'less than 10 feet'. Even the 'whole house' protector
provided by your telco (for free) must be earthing short to this new
earth rod. Even the cable TV must connect to this ground rod (no
protector required to earth cable TV).


Warranty. It is so full of exemptions that nobody gets it honored.
For example, one of many exceptions states that a protector in the
building from any other manufacturer void the warranty. Read the fine
print. With so many exemptions, your claim will only replace the
protector.

As a renter, your best bet is to buy the 'whole house' protector.
Have the landlord install it and upgrade the earthing. Surge
protection is always about dissipating surge energy into earth.
Nothing will stop or absorb what three miles of sky cannot even stop.

Brownouts have zero relation to surge. Grounding is irrelevant to
brownouts. Brownouts are a low voltage where the appliance must keep
working or simply turn off. Surge protection (why that short earth
connection is critical) is about high voltage and high frequencies.
Brownouts are completely ignored by surge protection.

How common are surges? Maybe once every seven years. If the
building has better earthing, if the protection at the service
entrance is properly installed, and if distance between that service
entrance and computer is long; then even better protection exists.
Critical to effective protection on two wire or three wire circuits is
protection connected within feet to earth AND separation between
protector and electronics.

 

[NB]

Speak of the devil...

 

[Baron]

And why hasn't w_tom jumped in yet?

Give him time !

 

[[email protected]]

I think I'll add these portable GFCIs to major appliance circuits.
They do not address the electronics I was asking about in this
question but at least they'll add a small degree of safety. I feel
that disturbing the original wiring to install built-in GFCIs would be
more netative than any positives provided from them.

Would a few UPS units be worth investing in as a degree of surge
protection? I remember hearing once before that UPS devices provide
better surge protection than surge protectors in many cases... Any
truth to this? Do they provide any protection at all?

 

[w_tom]

Yes, please, why such high voltage?  My calculation of your numbers shows
2.4 ohms per foot for the 12ga (assuming) Romex.  Where do you find Romex
at 2.4 ohms per foot?  Unless by "something less" you mean "orders of
magnitude less."  Maybe your statement simply needs some clarification. 

You are calculating wire resistance. Wire resistance on a 50 foot
romex may be 0.2 ohms. Critical to surge protection is lowest wire
impedance. That 50 foot romex may also be 120 ohms impedance. One
is more related to wire diameter. Other is more related to wire
length.

Put a sharp bend in that wire. Does resistance increase? No. But
impedance increases. Why must proper earthing have no sharp bends?
It would increase impedance - not resistance.

Effective protectors work by earthing surges. That wall receptacle
wire is woefully too long, has sharp bends, had splices, is bundled
with other wires, etc. Each point conspires to make it only a safety
ground (equipment ground) and not earth ground.

Why does a plug-in UPS not even claim such protection? Where is its
low impedance earthing wire? Where is that dedicated, low impedance
earthing wire? Does not exist.

Two 'top of the front page' articles entitled "Protecting Electrical
Devices from Lightning Transients" in Electrical Engineering Times do
not discuss power strip or UPS as protection. Article instead
discusses effective protection including wire impedance and earth
ground.
http://www.planetanalog.com/showArticle.jhtml?articleID=201807127
http://www.planetanalog.com/showArticle.jhtml?articleID=201807830

 

[w_tom]

Would a few UPS units be worth investing in as a degree of surge
protection?  I remember hearing once before that UPS devices provide
better surge protection than surge protectors in many cases... Any
truth to this?  

UPS provides better protection when myths are promoted. Review its
numeric specs. Where does it list each type of surge and protection
from that surge? Nothing. No numbers. Does not claim effective
protection. Even its joules rating is woefully smaller - but somehow
is better protection? No according to that number.. Demonstrated: so
many claim a UPS is better when they don't even read the numbers.
Subjective reasoning (ignore the numbers) resulted in 'junk science'
UPS recommendatoin.

UPS claims surge protection only because it does have some joules
numbers. Sufficient for many to *know* using subjective reasoning.
But near zero surge protection. Recommendatioin without even learning
the numbers. Common is for the naive to make such claims only
because that was the first thing heard: UPS provides better
protection. So many did not even read the numbers - but somehow knew.

Please post those UPS spec numbers that even claim to provide surge
protection. Even the manufacturer doesl not publish such claims.

 

[bud--]

..
Geez - NB and Baron are psychic...

The best information on surges and surge protection I have seen is in a
guide from the IEEE at:
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf

And a guide from the US NIST at:
http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf

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

Effective protectors work by earthing surges. That wall receptacle
wire is woefully too long

..
The IEEE guide explains plug-in suppressors work primarily by CLAMPING
(limiting) the voltage on all wires (signal and power) to the common
ground at the suppressor. Plug-in suppressors do not work primarily by
earthing (or stopping or absorbing). The guide explains earthing occurs
elsewhere. (Read the guide starting pdf page 40).
..

A properly earthed 'whole house' protector is also the only solution
to protecting GFCIs.

..
According to NIST guide, US insurance information indicates equipment
most frequently damaged by lightning is
computers with a modem connection
TVs, VCRs and similar equipment (presumably with cable TV
connections).
All can be damaged by high voltages between power and signal wires.

To limit the voltage between power and phone or cable wires the entry
protectors for phone and cable have to connect with *short* ground wires
to the earthing wire at the power service.

And if you are using a plug-in suppressor all interconnected equipment
needs to be connected to the same plug-in suppressor, or interconnecting
wires need to go through the suppressor. External connections, like
phone, also need to go through the suppressor. Connecting all wiring
through the suppressor prevents damaging voltages between power and
signal wires. These multiport suppressors are described in both guides.
..

A surge protector works by dissipating surge energy in earth.
However, if a tiny 100 amp surge is grounded by a power strip
protector, then the 50 feet of grounded romex means the protector is
at something less than 12,000 volts.

..
If a power line surge creates a 1,000A current to earth with a very good
resistance to earth of 10 ohms, the power system ground rises 10,000V
above 'absolute' earth potential. Much of the effectiveness of surge
protection is keeping the power and phone and cable wires at the same
potential with all of them floating up to 10,000V.

At a plug-in suppressor all the wires may also can float up to a
relatively high voltage. See the IEEE guide starting pdf page 40 for a
surge coming in on a cable service.
..

This
is why only responsible companies sell 'whole house' protectors - ie
Keison, Square D, Cutler-Hammer, Intermatic, Leviton, Siemens, GE,
etc.

..
All of w_'s "responsible" companies except SquareD make plug–in
suppressors.
For its "best" service panel suppressor SquareD says "electronic
equipment may need additional protection by installing plug-in
[suppressors] at the point of use."

Contrary to w_'s rant, both the IEEE and NIST guides say plug-in
suppressors are effective.

Never seen – a source that agrees with w_ that plug-in suppressors are
NOT effective.

 

[[email protected]]

UPS provides better protection when myths are promoted. Review its
numeric specs. Where does it list each type of surge and protection
from that surge? Nothing. No numbers. Does not claim effective
protection. Even its joules rating is woefully smaller - but somehow
is better protection? No according to that number.. Demonstrated: so
many claim a UPS is better when they don't even read the numbers.
Subjective reasoning (ignore the numbers) resulted in 'junk science'
UPS recommendatoin.

Manufacturers make untrue claims (marketing). People make untrue
claims (ignorance).

I'll leave it to you to figure out how both of these facts are related
to me posting questions here.

UPS claims surge protection only because it does have some joules
numbers. Sufficient for many to *know* using subjective reasoning.
But near zero surge protection. Recommendatioin without even learning
the numbers. Common is for the naive to make such claims only
because that was the first thing heard: UPS provides better
protection. So many did not even read the numbers - but somehow knew.

Please post those UPS spec numbers that even claim to provide surge
protection. Even the manufacturer doesl not publish such claims.

First you say: "UPS claims surge protection only because it does have
some joules numbers."

Then you say: "Please post those UPS spec numbers that even claim to
provide surge protection. Even the manufacturer doesl [sic] not
publish such claims."

I'm not interested in proving the answer to the question that I asked
to you but I do suggest that you decide to perpetuate non-
contradictory statements. It might make your life easier.

It's amazing to see someone use the words "subjective reasoning" twice
while answering a simple electronics/electrical question. You clearly
are the resident troll, aren't you?

Don't worry all, I won't feed him again.

 

[w_tom]

First you say: "UPS claims surge protection only because it does have
some joules numbers."

Then you say: "Please post those UPS spec numbers that even claim to
provide surge protection. Even the manufacturer doesl [sic] not
publish such claims."

I'm not interested in proving the answer to the question that I asked
to you but I do suggest that you decide to perpetuate non-
contradictory statements. It might make your life easier.

The statements are not contradictory. Manufacturers are held
responsible for claims in numeric specs. So no protection claims
exist there. Subjective claims made in sales brochures can say most
anything.

UPS manufacturer does not list each type of surge and does not claim
protection from each type in numeric specs.

However the manufacturer must claim a joules number. Where are
those MOVs? Not stated. So what are they protecting from? Does the
existence of joules mean surge protection exists? Of course not. But
that is sufficient to suggest "surge protection" in a color glossy
brochure. Now a retail salesman can claim the UPS provides surge
protection.

UPS provides no effective surge protection as others have also
noted. Any claims that a UPS provides protection are based only in
subjective reasoning from color brochures. It says "surge
protection". Therefore it provides protection from ALL types of
surges? Nonsense. Since that joules number is all but zero - then
subjective reasoning can claim effective protection even though
numbers say otherwise.

Where does a plug-in UPS manufacturer made numeric protection
claims? Well, the UPS does provide protection from a type of surge
that typically causes no damage. That means it protects from surges
that typically cause damage? Again, a conclusion based only upon
subjective reasoning. If we assume all surges are same type, then a
subjective conclusion can be rationalized. No protection claim from
typically destructive surges exists in numeric spec sheets because no
such protection exists.

Why does the manufacturer list joules - a number? When posting
spin, numbers must be avoided. But that numbers is required per a
standard. What does that joules numbers say? Protection is so
pathetically small as to be non-existent. Near zero is not zero
accordig to subjective claims on color glossy sales brochures. But
the manufacturer cannot and does not claim protection where claims
actually mean something: in numeric specifications.

Effective protection has a short connection to earth. Protection
means energy must be dissipated harmlessly someplace. Will those near
zero joules somehow absorb all that surge energy? Of course not. But
absorbing all that energy is what a UPS must do to provide effective
surge proetction. No wonder the manufacturer refuses to define
protection where it matters - in numeric spec sheets.

 

[w_tom]

Manufacturers make untrue claims (marketing).  People make untrue
claims (ignorance).

My posts said same.

 

[w_tom]

Does Romex make a 16 gauge building wire? Does the NEC allow it? You
seem to be saying this is so. Kindly confirm.
...
Please explain how and why. Concise mathematical verification, with
references, preferred.

Read cited EE Times. Other sources exist including ARRL handbooks
and QST articles. Concepts are also provided by publications from an
industry benchmark - Polyphaser. Start with:
http://www.polyphaser.com/technical_notes.aspx

Is that 50 foot romex 0.2 ohms or 0.1 ohms resistance? Irrelevant.
When compared to a relevant number (wire impedance), 0.1 and 0.2 are
equivalent. Why confuse resistance with impedance? To create
effective protection, impedance of an earthing connection must be
extremely low. Polyphaser makes a protector that has no connection to
earth ground. Impedance is so critical that the Polyphaser protector
is mounted ON earth ground - zero foot connection.