Surge Protected wall plate?

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Tom Morgan

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Sep 5, 2012, 3:52:49 AM9/5/12
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Hi all,

In the middle of redecorating, and it's time to make exciting decisions about cable management.

Does anyone know if you can get wallplates / mounting boxes which have surge protection built in? I was going to add some more plugs for behind the AV unit but really I'd need them surge protected, and I'm trying to avoid having a 4-way kicking around.

I found this - http://www.amazon.com/Power-Sentry-Wallplate-Surge-Protector/dp/B001F5OW9O - but it's very US, and I haven't found a UK equivalent.

Any help gratefully received!

-tom

Andrew Gabriel

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Sep 5, 2012, 4:11:17 AM9/5/12
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In article <67a90198-37cb-49b1...@googlegroups.com>,
Tom Morgan <tom.r....@gmail.com> writes:
> Hi all,
>
> In the middle of redecorating, and it's time to make exciting decisions about cable management.
>
> Does anyone know if you can get wallplates / mounting boxes which have surge protection built in? I was going to add some more plugs for behind the AV unit but really I'd need them surge protected, and I'm trying to avoid having a 4-way kicking around.

What surges do you get?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Tom Morgan

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Sep 5, 2012, 4:26:24 AM9/5/12
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Is this the part where you tell me I shouldn't be worrying about surge protection?! ;)

Seriously though, do RCD's offer any benefit at all over lightening strikes or random power surges (unlikely but possible?). We have a "modern" RCD unit, but I don't know if that offers any benefit...hence me using surge protection 4-ways on 'expensive' items, like TVs, computers etc.

-tom


On Wednesday, 5 September 2012 09:11:17 UTC+1, Andrew Gabriel wrote:
> In article <67a90198-37cb-49b1...@googlegroups.com>,
>

Dave Liquorice

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Sep 5, 2012, 5:01:00 AM9/5/12
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On Wed, 5 Sep 2012 01:26:24 -0700 (PDT), Tom Morgan wrote:

> Is this the part where you tell me I shouldn't be worrying about surge
> protection?! ;)

In a word yes. B-)

> Seriously though, do RCD's offer any benefit at all over lightening
> strikes ...

Unless you spend *SERIOUS* amounts of money nothing is going to protect
against a lightening strike within about 1/2 a mile.

> or random power surges (unlikely but possible?).

Do you notice your lights flickering normally, may need a good 'ole
filament lamp to see such voltage variations.

> We have a "modern" RCD unit, but I don't know if that offers any
> benefit...

None at all, might be worse as a "surge" might unbalance things and trip
the RCD. MCB's react quicker than fuses to overloads but I suspect that
with a surge the equipment will have already gone phut to protect the
MCB. B-)

--
Cheers
Dave.



John Rumm

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Sep 5, 2012, 5:47:12 AM9/5/12
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On 05/09/2012 08:52, Tom Morgan wrote:
> Hi all,
>
> In the middle of redecorating, and it's time to make exciting
> decisions about cable management.
>
> Does anyone know if you can get wallplates / mounting boxes which
> have surge protection built in? I was going to add some more plugs
> for behind the AV unit but really I'd need them surge protected, and
> I'm trying to avoid having a 4-way kicking around.

So you want some normal mains sockets with surge protection?

> I found this -
> http://www.amazon.com/Power-Sentry-Wallplate-Surge-Protector/dp/B001F5OW9O
> - but it's very US, and I haven't found a UK equivalent.

Hmm good game. Most "surge protected" sockets etc have nothing more than
a MOV in them to shunt spikes etc. You can add exactly the same
protection to a normal socket with one of these:

http://cpc.farnell.com/epcos/b72207s0251k101/varistor-19-0j-250vac/dp/RE03675

(you can see why the makers like selling the surge protected versions at
twice the price!)

However if you need protection from particularly troublesome mains then
you would need to look at a proper mains conditioner or at least a line
interactive UPS


--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

Owain

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Sep 5, 2012, 6:17:40 AM9/5/12
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On Sep 5, 10:47 am, John Rumm wrote:
> Hmm good game. Most "surge protected" sockets etc have nothing more than
> a MOV in them to shunt spikes etc. You can add exactly the same
> protection to a normal socket with one of these:
>
> http://cpc.farnell.com/epcos/b72207s0251k101/varistor-19-0j-250vac/dp...
>
> (you can see why the makers like selling the surge protected versions at
> twice the price!)

On the other hand, some of the makers do have apparently rather
generous payouts for damaged equipment. I have no idea whether they do
actually pay out or under what circumstances.

Owain

Andrew Gabriel

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Sep 5, 2012, 7:21:26 AM9/5/12
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In article <9282fcf7-1d43-4f03...@v15g2000yqi.googlegroups.com>,
There really aren't many scenarios where the MOV will help.
If you get a floating neutral and your supply creeps up to
400V, either the MOV won't trigger, or it will blow up.
The scenarios where you get more than 400V mains voltage
are vanishingly small. Lightning strikes tend to generate
common mode spikes which the MOV won't see, or large voltages
between differently earthed parts, which again this won't
trap. Like David said, you can protect against lightning,
but it will probably cost you more than your kit is worth.
It's done on things like radio masts where the kit is more
valuable and an interruption in service is not desirable.
You can't simply buy something and plug it in though - it
requires some special earthing design across the premises,
as well as filters.

The Natural Philosopher

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Sep 5, 2012, 8:06:32 AM9/5/12
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Tom Morgan wrote:
> Is this the part where you tell me I shouldn't be worrying about
> surge protection?! ;)
>
> Seriously though, do RCD's offer any benefit at all over lightening
> strikes or random power surges (unlikely but possible?). We have a
> "modern" RCD unit, but I don't know if that offers any
> benefit...hence me using surge protection 4-ways on 'expensive'
> items, like TVs, computers etc.
>

No RCDs do not.
I have been in electronics for years, including in S Afgrica whose power
is poor in stability and absolutely liable to lightning strikes.

The major source of issues is not power line strikes - these generally
do not cause equipment damage due to the immmense loads on them waiting
to short them out.

I have seen lighting strikes *nearby* knock equipment silly - but not
via the mains. IN EVERY CASE THEY HAD WIRING CONNECTED TO THEM THAT RAN
A LONG WAY. Viz audio distribution lines to remote loudspeakers, alarm
wiring and telephone lines.

very near strikes can physically destroy the inputs of stuff connected
to these low voltage lines. Whilst you can fit surge arrestors to
telephone lines, they tend to fuck up ADSL.

So what I have seen buggered by nearby (not direct strikes) is

Audio amplifier output stages on outdoor sound systems.
Alarm inputs stages on large properties
Anything connected to a phone. I have had at least three Netgears gifted
to me that went 'odd' and never recovered after lightning storms. My
current Billion router goes 'odd' and needs a cold reboot sometimes, but
has survived.

I have had a direct strike on a telephone drop wire. The drop wire
itself vanished. I did find a black smear on te road underneath.

That destroyed the modem attached to it (but US Robotics had a 'lifetime
gurantee on all their modems, so cash free replacement) , the answering
machine attached to it, the serial card unto which the modem was
plugged, the parallel printer plugged into the same card..although I did
get HP to fix it under warranty..three boards replaced. After that the
arc jumped into the mains wiring, blew an unused TV socket out of the
wall - literally - and destroyed a TV beyond economic repair, and a
digital record deck to the point of needing repair - CMOS chip gone.

After that it ran up into the mains wiring and burnt a hole in the
carpet where a light flex was trailing over the carpet and another one
was tucked underneath it.

It cost the landlords insurance a complete rewire. They refused to
insure him without it.

None of the above with the possible exception of the TV and record deck
would have been protected with a surge arrestor.

None of the above was ever damaged by mains surges.


Conclusion. Mains surge arrestors are worth less than used toilet paper.

If you want protection against power outages, get a UPS.
If you want protection against telephone line surges, don't get a Netgear.
If you want protection against a direct strike, get insurance.





--
Ineptocracy

(in-ep-toc’-ra-cy) – a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

Owain

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Sep 5, 2012, 8:15:59 AM9/5/12
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On Sep 5, 12:21 pm, (Andrew Gabriel) wrote:
> There really aren't many scenarios where the MOV will help.
> If you get a floating neutral and your supply creeps up to
> 400V, either the MOV won't trigger, or it will blow up.
> The scenarios where you get more than 400V mains voltage
> are vanishingly small.

Is the MOV blowing up the criterion for getting the payout?

Looks like it is.

Q.- What happens if the Belkin product PASSES the testing procedure?
Belkin will have to conclude that the damage was NOT caused by the
Belkin product and will issue a denial letter. In order for us to
consider a claim, we must find evidence of a surge having passed
through the surge protector in question.

Q.- Does Belkin deal with a large number of claims?
A.- No. Considering how many surge protectors we sell per month (which
is over 1.7 million worldwide), our claims amount to less that 1/10th
of 1% of our sales.

(and presumably that's claims, not payouts)

That'll be how a £20 protector comes with a £175,000 Connected
Equipment warranty then.

I suppose it would payout if you were careless enough to connect the
surge protector to the mains through a 240-110V transformer connected
in step-up rather than step-down mode.

Owain

Grimly Curmudgeon

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Sep 5, 2012, 8:50:11 AM9/5/12
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On Wed, 5 Sep 2012 00:52:49 -0700 (PDT), Tom Morgan
<tom.r....@gmail.com> wrote:

>Any help gratefully received!

Surge protection is the biggest marketing con trick perpetrated on the
Great UK Public since the year dot.
Don't waste your money.
If you're really concerned, look into a whole-house solution (not
particularly cheap, but effective) or run your sensitive electronics
from a good UPS.

John Rumm

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Sep 5, 2012, 9:11:48 AM9/5/12
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On 05/09/2012 12:21, Andrew Gabriel wrote:
> In article <9282fcf7-1d43-4f03...@v15g2000yqi.googlegroups.com>,
> Owain <spuorg...@gowanhill.com> writes:
>> On Sep 5, 10:47 am, John Rumm wrote:
>>> Hmm good game. Most "surge protected" sockets etc have nothing more than
>>> a MOV in them to shunt spikes etc. You can add exactly the same
>>> protection to a normal socket with one of these:
>>>
>>> http://cpc.farnell.com/epcos/b72207s0251k101/varistor-19-0j-250vac/dp...
>>>
>>> (you can see why the makers like selling the surge protected versions at
>>> twice the price!)
>> On the other hand, some of the makers do have apparently rather
>> generous payouts for damaged equipment. I have no idea whether they do
>> actually pay out or under what circumstances.
>
> There really aren't many scenarios where the MOV will help.

Indeed - was not suggesting they will achieve much in most cases, but
was just highlighting that is what counts for surge suppression in many
COTS mains extensions etc.

There are a few applications of them where they can help a little - they
are not bad at snubbing spikes resulting from inductive back voltages on
switching.

For example, I have a twin tape deck that always used to cause an
audible click on any adjacent hifi kit when switched on or off. Adding a
MOV to its mains lead dramatically improved it.

NT

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Sep 5, 2012, 9:16:30 AM9/5/12
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On Sep 5, 8:52 am, Tom Morgan <tom.r.mor...@gmail.com> wrote:
> Hi all,
>
> In the middle of redecorating, and it's time to make exciting decisions about cable management.
>
> Does anyone know if you can get wallplates / mounting boxes which have surge protection built in? I was going to add some more plugs for behind the AV unit but really I'd need them surge protected, and I'm trying to avoid having a 4-way kicking around.
>
> I found this -http://www.amazon.com/Power-Sentry-Wallplate-Surge-Protector/dp/B001F...- but it's very US, and I haven't found a UK equivalent.
>
> Any help gratefully received!
>
> -tom

The benefits of surge absorbers on mains are approximately zero. The
downside is fire risk. If you're running on an inductive generator
switching a heavy load plus have something relatively sensitive
connected, they can help reduce load dump transients - but other than
that they're pretty much useless.

They have nowhere near the surga absorbing ability to handle
lightning. All appliances need to be and normally are able to handle
all real life mains voltage transients, other than lightning.
Computers etc have far more protection against this built in than any
MOV can offer.

If you still want some I can fit some 50p surge absorbers to some
sockets and charge you an extra fiver each.


NT

The Natural Philosopher

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Sep 5, 2012, 9:38:51 AM9/5/12
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Grimly Curmudgeon wrote:
> On Wed, 5 Sep 2012 00:52:49 -0700 (PDT), Tom Morgan
> <tom.r....@gmail.com> wrote:
>
>> Any help gratefully received!
>
> Surge protection is the biggest marketing con trick perpetrated on the
> Great UK Public since the year dot.

No, thats solar panels and windmills.

It cant be higher than third.

Arguably its behind die=soon vacuum cleaners as well

> Don't waste your money.
> If you're really concerned, look into a whole-house solution (not
> particularly cheap, but effective) or run your sensitive electronics
> from a good UPS.


Which will get blown up instead.

wes...@gmail.com

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Sep 5, 2012, 9:42:22 AM9/5/12
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On Wednesday, September 5, 2012 4:26:24 AM UTC-4, Tom Morgan wrote:
> Is this the part where you tell me I shouldn't be worrying about surge
> protection?! ;) Seriously though, do RCD's offer any benefit at all over lightening strikes or random power surges (unlikely but possible?).

Your telco's $multi-million switching computer is connected to overhead wires all over town. Suffers about 100 surges with each storm. How often is your town without phone service for four days while they replace that computer? Never? Because protection from direct lightning strikes is routine.

But never provided by some 2 cm part that must either block or absorb a surge.

Well proven and inexpensive solutons means nobody even know the direct lightning strike occurred. But another device, unformatunately also called a protector, does not even claim to protect from destructive surges.

A destrutive surge is hundreds of thousands of joules. Where does that energy dissiapte? That is the only solution found in every facility that cannot have damage. They also do not waste money on protectors adjacent to equipment. They need protection. Because 100 surges with each storm means no damage even to a protector.

How does the millimeters gap in an RCD stop what three kilometers of sky could not? Anything that claims to block or absorb a surge is best called an urban myth. RCD is for another (completely different) anomoly.

Andrew Gabriel

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Sep 5, 2012, 10:30:22 AM9/5/12
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In article <Xridnd9QjscK0trN...@brightview.co.uk>,
John Rumm <see.my.s...@nowhere.null> writes:
> There are a few applications of them where they can help a little - they
> are not bad at snubbing spikes resulting from inductive back voltages on
> switching.
>
> For example, I have a twin tape deck that always used to cause an
> audible click on any adjacent hifi kit when switched on or off. Adding a
> MOV to its mains lead dramatically improved it.

MOV isn't a good solution for regular spikes, because each spike
uses up (burns out) a part of the device. When it's absorbed its
total Joule rating, it won't work anymore.

Andy Burns

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Sep 5, 2012, 4:45:50 PM9/5/12
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wes...@gmail.com wrote:

> How often is your town without phone service for four days
> while they replace that computer? Never? Because protection from
> direct lightning strikes is routine.

Oh, have the pikeys made-off with Bob's signature?

John Rumm

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Sep 5, 2012, 6:10:23 PM9/5/12
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You can only walk over the bridge so many times before waking what lies
beneath!

John Rumm

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Sep 5, 2012, 6:11:57 PM9/5/12
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On 05/09/2012 15:30, Andrew Gabriel wrote:
> In article <Xridnd9QjscK0trN...@brightview.co.uk>,
> John Rumm <see.my.s...@nowhere.null> writes:
>> There are a few applications of them where they can help a little - they
>> are not bad at snubbing spikes resulting from inductive back voltages on
>> switching.
>>
>> For example, I have a twin tape deck that always used to cause an
>> audible click on any adjacent hifi kit when switched on or off. Adding a
>> MOV to its mains lead dramatically improved it.
>
> MOV isn't a good solution for regular spikes, because each spike
> uses up (burns out) a part of the device. When it's absorbed its
> total Joule rating, it won't work anymore.

Probably not a problem in this situation - I doubt its been turned on
more than 50 times in the 20 years I have owned it ;-)

Mike Tomlinson

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Sep 6, 2012, 5:39:08 AM9/6/12
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In article <5324d69e-b2f4-410b...@googlegroups.com>,
wes...@gmail.com writes

[usual scaremongering shite snipped]

Hey ho, w_twat rides again.

--
(\_/)
(='.'=)
(")_(")

Mike Tomlinson

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Sep 6, 2012, 5:45:49 AM9/6/12
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In article <k27f88$5tv$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> writes

>Conclusion. Mains surge arrestors are worth less than used toilet paper.

I see westom1, aka w_tom, aka w_tom1, aka w_twat, has crawled out from
under his rock again.

Surge protectors are just that, they work to shunt surges (voltage
peaks, voltage spikes) to earth to prevent them reaching the downstream
equipment. They don't claim to protect against lightning strikes.

But they're only useful if they have common mode protection - a MOV
between L&N, L&E and N&E. El-cheapo models have just the one MOV across
L&E.

Mike Tomlinson

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Sep 6, 2012, 5:52:24 AM9/6/12
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In article <bb6d5a66-c6b3-4e88...@k20g2000vbk.googlegroup
s.com>, Owain <spuorg...@gowanhill.com> writes

>"In order for us to
>consider a claim, we must find evidence of a surge having passed
>through the surge protector in question."

i.e. they want to see the blown-up kit the surge protector was supposed
to be protecting.

Also, MOVs wear out - they become less and less effective with each
surge they shunt to earth and eventually stop working altogether. Some
of the better surge protectors have a warning lamp to tell you when this
has happened.

meow...@care2.com

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Sep 6, 2012, 6:38:16 AM9/6/12
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On Thursday, September 6, 2012 10:45:59 AM UTC+1, Mike Tomlinson wrote:
> In article <k27f88$5tv$1...@news.albasani.net>, The Natural Philosopher
>
> <t...@invalid.invalid> writes
>
>
>
> >Conclusion. Mains surge arrestors are worth less than used toilet paper.
>
>
>
> I see westom1, aka w_tom, aka w_tom1, aka w_twat, has crawled out from
>
> under his rock again.

nope


> Surge protectors are just that, they work to shunt surges (voltage
>
> peaks, voltage spikes) to earth to prevent them reaching the downstream
>
> equipment.

Mains connected appliances are capable of handling greater 'surges' than the surge protectors. They are simply pointless. Anyone with any electronics skills can look at typical power supply front ends and see a far more effective means of dealing with voltage peaks than a variable resistor across the mains.


> They don't claim to protect against lightning strikes.
>
>
>
> But they're only useful if they have common mode protection - a MOV
>
> between L&N, L&E and N&E. El-cheapo models have just the one MOV across
>
> L&E.

Exactly how are they useful? What voltage do you believe appliances are unable to survive, but that MOVs eliminate? What is the source of these surges in your opinion?

Hint: the impedance of the mains incomer is a tiny fraction of the impedance of a conducting MOV


NT

The Natural Philosopher

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Sep 6, 2012, 8:36:48 AM9/6/12
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That is NOT a given. its a MAY.


See wikis comments
================================================================

There are several issues to be noted regarding behavior of transient
voltage surge suppressors (TVSS) incorporating MOVs under over-voltage
conditions. Depending on the level of conducted current, dissipated heat
*may* be insufficient to cause failure, but *may* degrade the MOV device
and reduce its life expectancy. If excessive current is conducted by a
MOV, it may fail catastrophically, keeping the load connected, but now
without any surge protection. A user may have no indication when the
surge suppressor has failed. Under the right conditions of over-voltage
and line impedance, it may be possible to cause the MOV to burst into
flames[3], the root cause of many fires[4] and the main reason for
NFPA’s concern resulting in UL1449 in 1986 and subsequent revisions in
1998 and 2009. Properly designed TVSS devices must not fail
catastrophically, resulting in the opening of a thermal fuse or
something equivalent that only disconnects MOV devices.
============================================================

And MOVS are not applied between phase and earth. That would result in
instant RCD operation. They are applied ACROSS phases to limit spikes on
the live with respect to the neutral from e.g. disconnection of
inductive loads.

That is in fact the only situation in which they do anything useful at all.

Almost nothing is permitted to go between live and earth or neutral and
earth. Typically only RF suppression caps and those in themselves
represent a PITA with RCDS.

mains surges were never a problem really with transformer coupled LV DC
supplies. But they are capable of providing high peak currents and
volategs into SMPS designs and blowing the primary rectifiers..

Grimly Curmudgeon

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Sep 6, 2012, 8:38:47 AM9/6/12
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On Wed, 5 Sep 2012 06:42:22 -0700 (PDT), wes...@gmail.com wrote:

>Your telco's

Eff off.

Mike Tomlinson

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Sep 6, 2012, 9:26:00 AM9/6/12
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In article <k2a5d1$a24$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> writes

>And MOVS are not applied between phase and earth.

Just about every maker of surge protection devices disagrees with you,
as a quick google demonstrates.

Example:

http://www.lightningcontrol.com/FAQ%27s.htm

>Almost nothing is permitted to go between live and earth or neutral and
>earth.

Take a look inside some surge protectors that provide common mode
protection then come back and tell me that again.

wes...@gmail.com

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Sep 6, 2012, 9:58:39 AM9/6/12
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On Thursday, September 6, 2012 8:36:49 AM UTC-4, The Natural Philosopher wrote:
And MOVS are not applied between phase and earth. That would result in instant RCD operation.


Discussion is confused by two completely different devices that, unfortunately, share a same name. An effective protector is from each phase to earth. It never tips an RCD (or GFCI) because the protector looks like an open circuit (disconnected) when a surge does not exist.

Effective protectors are for lightning strikes (and other lesser surges). Effective protectors even have numbers that say it is for protection from lightning - ie 50,000 amps.

Undersized 'profit center' protectors are for tiny surges that typically cause no appliance damage. As others have noted, protection already inside appliances makes that tiny surge (and that tiny protector) irrelevant. Those tiny protectors are rated maybe in hundreds of joules. The surge that can overwhelm protection already inside appliances is something like hundreds of thousands of joules.

A protector for appliance protection is for surges that are hundreds of thousands of joules. Is provided by other and more responsible companies including Keison, ABB, Siemens, General Electric and others. That undersized protector for tiny (irrelevant ) surges is often promoted with brand names such as Belkin and Tripplite.

An effective protector must remains functional even after direct lightning strikes. Protectors that are catastrophically destroyed (a potential house fire) or that degrade significantly are ineffective. Are profit centers sold because it happens to have a same name even though it is a completely different device.

An effective protector means surges, such as direct lightning strikes, do not overwhelm protection already inside appliances. Do not even harm the protector. These superior devices, that cost less money, make the 'always required' connection from phase to earth. Only when a surge exists. And too quickly to trip an RCD.

The Natural Philosopher

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Sep 6, 2012, 10:13:28 AM9/6/12
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Mike Tomlinson wrote:
> In article <k2a5d1$a24$1...@news.albasani.net>, The Natural Philosopher
> <t...@invalid.invalid> writes
>
>> And MOVS are not applied between phase and earth.
>
> Just about every maker of surge protection devices disagrees with you,
> as a quick google demonstrates.
>
> Example:
>
> http://www.lightningcontrol.com/FAQ%27s.htm
>

Whivh has NOTGING to do with surge arrestors sold fr domestic use
downstream of an RCD.

>> Almost nothing is permitted to go between live and earth or neutral and
>> earth.
>
> Take a look inside some surge protectors that provide common mode
> protection then come back and tell me that again.
>

Domestic units do not provide such protection.

The Natural Philosopher

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Sep 6, 2012, 10:49:22 AM9/6/12
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Except that lightning upstream of my 11KV transformer often trips my
RCD, so its hard to see how anything that acts slow enough to absorb a
full lightning common mode surge, which patently DOES trip an RCD, can
function effectively *without* tripping one.

In short common mode protection MUST be upstream of the RCD.

Domestic surge protection devices are NOT common mode.

Andrew Gabriel

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Sep 6, 2012, 11:06:42 AM9/6/12
to
In article <k2ab28$lnr$2...@news.albasani.net>,
The Natural Philosopher <t...@invalid.invalid> writes:
> Mike Tomlinson wrote:
>> In article <k2a5d1$a24$1...@news.albasani.net>, The Natural Philosopher
>> <t...@invalid.invalid> writes
>>
>>> And MOVS are not applied between phase and earth.
>>
>> Just about every maker of surge protection devices disagrees with you,
>> as a quick google demonstrates.
>>
>> Example:
>>
>> http://www.lightningcontrol.com/FAQ%27s.htm
>>
>
> Whivh has NOTGING to do with surge arrestors sold fr domestic use
> downstream of an RCD.
>
>>> Almost nothing is permitted to go between live and earth or neutral and
>>> earth.
>>
>> Take a look inside some surge protectors that provide common mode
>> protection then come back and tell me that again.
>>
>
> Domestic units do not provide such protection.

partly because it's impossible to do so in a plug-in device - it
needs to be designed into the premises wiring and building earthing
system. By the time you're out as far as a socket outlet, the earth
impedance is too high for common mode spike protection to work.

Mike Tomlinson

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Sep 6, 2012, 11:55:22 AM9/6/12
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En el art�culo <k2ad5j$pu6$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> escribi�:

>Except that

You're responding to a well-known idiot for whom Usenet is a write-only
medium and who only ever responds in his own particular dogmatic fashion
to posts about surge protection. He probably has a Google Alert set up
to email him when a thread such as this one is started.

Search Google groups for w_tom, w_tom1, westom, westom1 AND 'surge
protection' before you waste any more time on him.

Mike Tomlinson

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Sep 6, 2012, 11:56:42 AM9/6/12
to
En el art�culo <k27nlu$f8c$1...@dont-email.me>, Andrew Gabriel
<and...@cucumber.demon.co.uk> escribi�:

>MOV isn't a good solution for regular spikes, because each spike
>uses up (burns out) a part of the device. When it's absorbed its
>total Joule rating, it won't work anymore.

According to TNP and the saintly Wikipedia, which of course is never
wrong, you are incorrect. I know who I believe.

The Natural Philosopher

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Sep 6, 2012, 12:27:44 PM9/6/12
to
Mike Tomlinson wrote:
> En el artículo <k2ad5j$pu6$1...@news.albasani.net>, The Natural Philosopher
> <t...@invalid.invalid> escribió:
>
>> Except that
>
> You're responding to a well-known idiot for whom Usenet is a write-only
> medium and who only ever responds in his own particular dogmatic fashion
> to posts about surge protection. He probably has a Google Alert set up
> to email him when a thread such as this one is started.
>
> Search Google groups for w_tom, w_tom1, westom, westom1 AND 'surge
> protection' before you waste any more time on him.
>

Yes. And basically who is confusing whole house protection - for which I
utterly agree common mode protection is ideal and possible, if probably
unnecessary - with what comes in a wall plate. which assuredly is not.

tony sayer

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Sep 6, 2012, 3:13:45 PM9/6/12
to
In article <k2aiu1$7ec$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> scribeth thus
>Mike Tomlinson wrote:
>> En el art�culo <k2ad5j$pu6$1...@news.albasani.net>, The Natural Philosopher
>> <t...@invalid.invalid> escribi�:
>>
>>> Except that
>>
>> You're responding to a well-known idiot for whom Usenet is a write-only
>> medium and who only ever responds in his own particular dogmatic fashion
>> to posts about surge protection. He probably has a Google Alert set up
>> to email him when a thread such as this one is started.
>>
>> Search Google groups for w_tom, w_tom1, westom, westom1 AND 'surge
>> protection' before you waste any more time on him.
>>
>
>Yes. And basically who is confusing whole house protection - for which I
>utterly agree common mode protection is ideal and possible, if probably
>unnecessary - with what comes in a wall plate. which assuredly is not.
>
>
>


We look after some communication and radio transmission sites. On
those its all down to shunting critical paths and the correct bonding.

I don't think theres one surge arrestor in any of them !...


--
Tony Sayer

Peter Crosland

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Sep 6, 2012, 4:58:36 PM9/6/12
to
On 05/09/2012 08:52, Tom Morgan wrote:
> Hi all,
>
> In the middle of redecorating, and it's time to make exciting decisions about cable management.
>
> Does anyone know if you can get wallplates / mounting boxes which have surge protection built in? I was going to add some more plugs for behind the AV unit but really I'd need them surge protected, and I'm trying to avoid having a 4-way kicking around.
>
> I found this - http://www.amazon.com/Power-Sentry-Wallplate-Surge-Protector/dp/B001F5OW9O - but it's very US, and I haven't found a UK equivalent.
>
> Any help gratefully received!

They don't work effectively so don't waste your money.


--
Peter Crosland

wes...@gmail.com

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Sep 7, 2012, 10:04:48 PM9/7/12
to
On Thursday, September 6, 2012 3:26:24 PM UTC-4, tony sayer wrote:
We look after some communication and radio transmission sites. On those its all down to shunting critical paths and the correct bonding. I don't think theres one surge arrestor in any of them!

Of course. Best protection is a short wire to earth; not a protector. Some of the best protection has no protectors. But always has that short (low impedance) connection to earth. Protectors are implemented only when an incoming utility wire cannot connect directly to the earthing electrode. Protectors do not do protection. A protector is a connecting device. It connects (bonds) to earth when the incoming wire cannot be earthed directly. Many facilities have no protectors. But must always bond low impedance to earth. Because earth ground - not a protector - does the protection.

alan

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Sep 9, 2012, 5:45:44 PM9/9/12
to
On 06/09/2012 10:45, Mike Tomlinson wrote:

> But they're only useful if they have common mode protection - a MOV
> between L&N, L&E and N&E. El-cheapo models have just the one MOV across
> L&E.
>

http://www.zerosurge.com/technical-info/truth-about-movs/

Isn't a high voltage more likely to travel down the coax from an aerial
or LNB when the aerial or dish are struck?

--
mailto:news{at}admac(dot}myzen{dot}co{dot}uk

alan

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Sep 9, 2012, 5:55:40 PM9/9/12
to
On 06/09/2012 10:52, Mike Tomlinson wrote:
> Some
> of the better surge protectors have a warning lamp to tell you when this
> has happened.
>

And a lot of web sites that demonstrate that the LED that informs you
that the surge protector is working perfectly is still lit when the MOVs
have been removed from the circuit.

Mike Tomlinson

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Sep 9, 2012, 11:19:46 PM9/9/12
to
En el art�culo <504d105c$0$7309$5b6a...@news.zen.co.uk>, alan
<ju...@admac.myzen.co.uk> escribi�:

>And a lot of web sites that demonstrate that the LED that informs you
>that the surge protector is working perfectly is still lit when the MOVs
>have been removed from the circuit.

Yes. ;-)

The "surge protection working' lamp was still illuminated on these:

http://jasper.org.uk/Boom.jpg

But you get what you pay for.

alan

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Sep 10, 2012, 2:33:45 AM9/10/12
to
On 10/09/2012 04:19, Mike Tomlinson wrote:

> But you get what you pay for.
>


You may be able to get them at the pound shops but they may also be in
the unsolicited catalogues pushed through your letterbox at a price that
is significantly higher. Price is often no indicator of quality

tony sayer

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Sep 10, 2012, 4:37:52 AM9/10/12
to
In article <504d0e09$0$1142$5b6a...@news.zen.co.uk>, alan
<ju...@admac.myzen.co.uk> scribeth thus
>On 06/09/2012 10:45, Mike Tomlinson wrote:
>
>> But they're only useful if they have common mode protection - a MOV
>> between L&N, L&E and N&E. El-cheapo models have just the one MOV across
>> L&E.
>>
>
>http://www.zerosurge.com/technical-info/truth-about-movs/
>
>Isn't a high voltage more likely to travel down the coax from an aerial
>or LNB when the aerial or dish are struck?
>

It will go where it thinks fit!, and that can be anywhere. Thats the
principle of the lightning conductor to provide an as low impedance path
as possible to Earth...

In a very close or direct strike if the aerial lead gets in the way then
thats usually vaporised. I wish now I'd have kept some pix I had of
instances like that!..
--
Tony Sayer

meow...@care2.com

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Sep 10, 2012, 4:45:45 AM9/10/12
to
On Monday, September 10, 2012 4:29:50 AM UTC+1, Mike Tomlinson wrote:
> En el artículo <504d105c$0$7309$5b6a...@news.zen.co.uk>, alan
>
> <junk@> escribió:
>
>
>
> >And a lot of web sites that demonstrate that the LED that informs you
>
> >that the surge protector is working perfectly is still lit when the MOVs
>
> >have been removed from the circuit.
>
>
>
> Yes. ;-)
>
>
>
> The "surge protection working' lamp was still illuminated on these:
>
>
>
> http://jasper.org.uk/Boom.jpg
>
>
>
> But you get what you pay for.

No, they're all equally useless


N
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