Surge Protectors

[[email protected]]

Are surge protectors based on grounding or diode clipping?




- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

 

[[email protected]]

Thanks for both replies.


- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

 

[GregS]

Both. Most surge suppressors have a conducts-on-overvoltage
element directly across the line, with a fuse or circuit breaker to
keep the fire hazard low. Additional elements that connect to the
protective ground pin are of secondary importance.

I would argue that. The differential surpressor is fine, but the common
mode surge can do more harm and a lot of noise problems. Using an isolation transformer
makes common mode problems impossible. Its a direct short to ground.

greg

 

[GregS]

The metal oxide in a MOV is certainly a semiconductor. The breakover
is due to avalanche multiplication rather than minority injection.
The oldest
ones were SiC (basically, just grinding wheels with electrodes bolted
on).
It has two leads, so it's a diode. It's made with a semiconductor, so
it's a semiconductor diode. It isn't a rectifier diode, though.
DIAC and current regulator two-terminal devices are also diodes,
but aren't simple PN junction types (don't really rectify).
Vacuum tubes are sometimes diodes, too (like my microwave oven's
magnetron).


The protective ground connection is, in most situations, carrying no
current. The MOVs that connect to that protective ground are not so
much
protecting the plugged-in device, as they are dumping transient energy
in
the building's wiring (protecting the building rather than the
appliance).
The internal suppressors on lots of consumer equipment only have
one MOV, across the line, not the full trio that is common in third-
party
suppressor modules.

I thought there were NO supressors in most consumer equipment
because its a liability.

Its the line to ground noise and surges that cause TTL computer type equipment
to BOMB OUT. Ground has everything to do with functioning circuits, that use ground
for reference. Of, course, its best not to use ground for reference.

greg

 

[[email protected]]

Well, here's is a disclosure of the biases which might be distorting my
thinking: In February and August 2001 I lost two external modems to lightning
(caused my line to be off-hook until disconnected modems) and someone on
usenet told me to tie a ground to the modem. That particular computer (Ampro
2210 80186 hooked up to 1980 HP2621a terminal) with modems had previously
survived 1988-1995 without problems (no phone surge supressor but one on
power). In 2008 I lost two LCD monitors the same week during light rain. I
am therefore excessively (and probably unreasonably) cautious of using
computers during bad weather. Also in 1980 I took two semesters of EE for
non-EEs (am a 1981 ChE).

- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

 

[[email protected]]

*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.


- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

 

[Cydrome Leader]

There should already be one inside the phone company's Network
Interface.

This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.

 

[bud--]

This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.

Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.

If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.

Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.

May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.

Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.

==========
If there is a strong surge on power wires, with no power service
suppressor, at about 6kV there is arc-over from the hot busbars to the
service panel enclosure. After the arc is established, the arc voltage
is hundreds of volts. Since the enclosure is connected to
ground-neutral-earthing electrode, most of the surge energy is dumped to
earth. A surge is a short event, thus a relatively high frequency event.
The impedance of the branch circuit greatly limits the current to a
plug-in suppressor (unless the branch circuit is very short) and thus
limits the energy that can reach a plug-in suppressor. For both these
reasons the energy dissipated in a plug-in suppressor is surprisingly small.

Neither service entrance or plug-in suppressors work by absorbing the
surge energy. But in the process of protecting, some energy is absorbed.

 

[Cydrome Leader]

This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.

Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.

If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.

Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.

May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.

Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.

The lab NIST uses is not the typical home people live in.

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.

 

[bud--]

[email protected] wrote:
*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.
There should already be one inside the phone company's Network
Interface.
This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.

Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.

If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.

Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.

May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.

Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.

The lab NIST uses is not the typical home people live in.

I have no idea what you are talking about. The discussion is ordinary
surge suppressors

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.

So don't get "cheap-o power strips". I use name brand suppressors with
high ratings.

UL1449 has, since 1998, required thermal discoinnects for overheating
MOVs. If a suppressor is UL1449 listed there is not much probability of
any problem. The author of the NIST guide has written "In fact, the
major cause of [surge suppressor] failures is a temporary overvoltage,
rather than an unusually large surge". TOV is, for example, a
distribution wire falling onto the secondary wires that go to your house.

 

[Cydrome Leader]

Cydrome Leader wrote:
[email protected] wrote:
*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.
There should already be one inside the phone company's Network
Interface.
This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.
Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.
If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.
Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.
May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.
Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.

The lab NIST uses is not the typical home people live in.

I have no idea what you are talking about. The discussion is ordinary
surge suppressors

yes, ordinary surge surpressors. go to the store, pick one up and tell me
what you find inside of it.

I'd be pleased to counter with the CPSC recall notice.

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.

So don't get "cheap-o power strips". I use name brand suppressors with
high ratings.

UL1449 has, since 1998, required thermal discoinnects for overheating
MOVs. If a suppressor is UL1449 listed there is not much probability of
any problem. The author of the NIST guide has written "In fact, the
major cause of [surge suppressor] failures is a temporary overvoltage,
rather than an unusually large surge". TOV is, for example, a
distribution wire falling onto the secondary wires that go to your house.

Again, if you really trust any UL markings on a power strip, go for it.

You do relized that UL doesn't even test most stuff, they sell stickers.
That's the business model. If you want to get more technical, they're
really a licensing company.

they have nothing at all to do with safety, at all, any more than iso 9001
has anything to do with quality.

It's possible you have some decent surge protectors, but you're 0.01% of
the market.

 

[bud--]

Cydrome Leader wrote:
[email protected] wrote:
*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.
There should already be one inside the phone company's Network
Interface.
This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.
Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.
If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.
Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.
May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.
Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.
The lab NIST uses is not the typical home people live in.

I have no idea what you are talking about. The discussion is ordinary
surge suppressors

yes, ordinary surge surpressors. go to the store, pick one up and tell me
what you find inside of it.

I'd be pleased to counter with the CPSC recall notice.

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.

So don't get "cheap-o power strips". I use name brand suppressors with
high ratings.

UL1449 has, since 1998, required thermal discoinnects for overheating
MOVs. If a suppressor is UL1449 listed there is not much probability of
any problem. The author of the NIST guide has written "In fact, the
major cause of [surge suppressor] failures is a temporary overvoltage,
rather than an unusually large surge". TOV is, for example, a
distribution wire falling onto the secondary wires that go to your house.

Again, if you really trust any UL markings on a power strip, go for it.

You do relized that UL doesn't even test most stuff, they sell stickers.
That's the business model. If you want to get more technical, they're
really a licensing company.

Complete nonsense.

In Europe equipment is mostly self-certified that it meets a standard.

UL tests almost all equipment it lists.
http://en.wikipedia.org/wiki/Underwriters_Laboratories
"the UL Mark requires independent third-party certification from UL"

Some equipment, like TVs are tested to fail safely - it is not practical
to test whether they work.

Much of the UL listed equipment - fuses, circuit breakers, switches, ...
- are tested to comply with a standard that requires “fitness for a
given use” and “service life”.Ordinary wall switches used in power
wiring are tested by UL to remain functional after 30,000 operations at
or above their current and voltage rating. (The test is a lot more
involved than that.)

For surge suppressors, under UL1449 suppressors are tested by UL for
let-through voltage under specified conditions followed by a series of
20 surges followed by a let-through voltage test again. If the second
let-through voltage dropped significantly the MOVs are deteriorating. A
suppressor has to be functional through all these tests. Further tests
are of a nature that the suppressor might fail. It must fail safely. As
in my last post, overheating MOVs must be disconnected safely.

Incidentally, I was the technical end of a UL panel shop.

they have nothing at all to do with safety, at all, any more than iso 9001
has anything to do with quality.

UL listing of electrical equipment has everything to do with safety.

It's possible you have some decent surge protectors, but you're 0.01% of
the market.

UL1449 listed suppressors have been tested to pass at least a minimum
floor of protection. Anyone can buy well known name brands and get
suppressors with high ratings like I do.

Francois Martzloff was the surge expert at the US-NIST and wrote the
NIST guide. He also has many published papers on surges. I have included
some of his information in previous posts.

In one of his papers Martzloff has written "in fact, the major cause of
[surge suppressor] failures is a temporary overvoltage, rather than an
unusually large surge". TOV is, for instance, a distribution wire
dropping onto the wires that go to your house. (This is, of course, not
a surge.)

Martzloff also suggests in the NIST guide that most equipment damage is
from high voltage between power and cable/phone wires. (This is
illustrated in the IEEE guide starting pdf page 40.)

The IEEE is the largest association of electrical and electronic
engineers in the US. The IEEE guide (a link was provided) was written by
the IEEE committee that covers surge protection devices. The IEEE guide
says plug-in suppressors are effective. The only 2 examples of
protection in the IEEE guide use plug-in suppressors.

Similarly, surge expert Martzloff says in the NIST guide (link provided)
that plug-in suppressors are effective.

Where is your source that says otherwise.

 

[Cydrome Leader]

Cydrome Leader wrote:
Cydrome Leader wrote:
[email protected] wrote:
*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.
There should already be one inside the phone company's Network
Interface.
This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.
Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.
If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.
Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.
May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.
Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.
The lab NIST uses is not the typical home people live in.
I have no idea what you are talking about. The discussion is ordinary
surge suppressors

yes, ordinary surge surpressors. go to the store, pick one up and tell me
what you find inside of it.

I'd be pleased to counter with the CPSC recall notice.

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.
So don't get "cheap-o power strips". I use name brand suppressors with
high ratings.

UL1449 has, since 1998, required thermal discoinnects for overheating
MOVs. If a suppressor is UL1449 listed there is not much probability of
any problem. The author of the NIST guide has written "In fact, the
major cause of [surge suppressor] failures is a temporary overvoltage,
rather than an unusually large surge". TOV is, for example, a
distribution wire falling onto the secondary wires that go to your house.

Again, if you really trust any UL markings on a power strip, go for it.

You do relized that UL doesn't even test most stuff, they sell stickers.
That's the business model. If you want to get more technical, they're
really a licensing company.

Complete nonsense.

In Europe equipment is mostly self-certified that it meets a standard.

UL tests almost all equipment it lists.
http://en.wikipedia.org/wiki/Underwriters_Laboratories
"the UL Mark requires independent third-party certification from UL"

Some equipment, like TVs are tested to fail safely - it is not practical
to test whether they work.

Much of the UL listed equipment - fuses, circuit breakers, switches, ...
- are tested to comply with a standard that requires ?fitness for a
given use? and ?service life?.Ordinary wall switches used in power
wiring are tested by UL to remain functional after 30,000 operations at
or above their current and voltage rating. (The test is a lot more
involved than that.)

For surge suppressors, under UL1449 suppressors are tested by UL for
let-through voltage under specified conditions followed by a series of
20 surges followed by a let-through voltage test again. If the second
let-through voltage dropped significantly the MOVs are deteriorating. A
suppressor has to be functional through all these tests. Further tests
are of a nature that the suppressor might fail. It must fail safely. As
in my last post, overheating MOVs must be disconnected safely.

Incidentally, I was the technical end of a UL panel shop.

they have nothing at all to do with safety, at all, any more than iso 9001
has anything to do with quality.

UL listing of electrical equipment has everything to do with safety.

It's possible you have some decent surge protectors, but you're 0.01% of
the market.

UL1449 listed suppressors have been tested to pass at least a minimum
floor of protection. Anyone can buy well known name brands and get
suppressors with high ratings like I do.

Francois Martzloff was the surge expert at the US-NIST and wrote the
NIST guide. He also has many published papers on surges. I have included
some of his information in previous posts.

In one of his papers Martzloff has written "in fact, the major cause of
[surge suppressor] failures is a temporary overvoltage, rather than an
unusually large surge". TOV is, for instance, a distribution wire
dropping onto the wires that go to your house. (This is, of course, not
a surge.)

Martzloff also suggests in the NIST guide that most equipment damage is
from high voltage between power and cable/phone wires. (This is
illustrated in the IEEE guide starting pdf page 40.)

The IEEE is the largest association of electrical and electronic
engineers in the US. The IEEE guide (a link was provided) was written by
the IEEE committee that covers surge protection devices. The IEEE guide
says plug-in suppressors are effective. The only 2 examples of
protection in the IEEE guide use plug-in suppressors.

Similarly, surge expert Martzloff says in the NIST guide (link provided)
that plug-in suppressors are effective.

Where is your source that says otherwise.

So, did martzloff test this item?

http://cpsc.gov/cpscpub/prerel/prhtml10/10184.html

what about this, who tested these? they were wired with reverse polarity,
even a $3 outlet tester would have found that:

http://cpsc.gov/cpscpub/prerel/prhtml04/04573.html

how about energizer branded products, were these tested:

http://cpsc.gov/cpscpub/prerel/prhtml04/04002.html

That's just a random sampling. These products and pretty much anything
similar are the most poorly constructed and designed products ever made,
next to coffee pots that lack power switches.

If you really expect some item that's about to burst into flames by just
being plugged in to protect anything when there's a power surge, you must
love living on the edge.

 

[bud--]

Cydrome Leader wrote:
Cydrome Leader wrote:
[email protected] wrote:
*+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
*+-ground and from one leg to the other. I guess that's a "delta" config.

Do surge supressors exist for two-line phone connections?

WOuld it make sence to put a surge suppressor (what kind?) on my
incoming phone line? Neighbors have complained of fried modems, but
curiously I don't remember anyone ever telling mtheir computer got fried.
There should already be one inside the phone company's Network
Interface.
This applies to the US-

there are surge and lightning arrestors on phone lines where they enter a residence, and they're
grounded to something good, like a water pipe for instance.

It works great.
Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

Now if lightning surges hit your power then what happens?

a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
to neutral or even line to ground.

What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
whatever? The numbers are made up, but concept is the same.

well, your ground ends up at 300 volts above actual earth ground where that device is located. This
assumes your ground has the same impedance as the current carrying conductors.

So now your computer isn't really grounded, and floating at a potential way off what the phone like
is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
wiring in your walls or whatever.

This is what blows up stuff like modems or devices that sit between your outlets and a phone line.
If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

The best move is to install a service entrance surge supressor. They'll clamp surges at the best
ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.
Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

You can easily test the resistance of your wiring at home too, and at the same time actually test
if your ground is solid.

connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
device using line to ground.

Depending on how your place is wired, you may find that under an actual load, your ground is really
awful. A volt meter won't pick crappy ground connections unless you are actually running real
current through it, so just reading 120 across hot and ground and saying "looks good" really
doesn't count.
May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
BX cable can really just be a big joke.
Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.
The lab NIST uses is not the typical home people live in.
I have no idea what you are talking about. The discussion is ordinary
surge suppressors
yes, ordinary surge surpressors. go to the store, pick one up and tell me
what you find inside of it.

I'd be pleased to counter with the CPSC recall notice.

Have you opened a "surge supressor" that the average person owns? It's
really surprising more don't catch on fire with no surges.

the construction quality tends to really really suck.

Even "name brand" items from tripp-lite are utter pieces of crap for the
most part. I've seen those catch fire, and these were made in USA ones.

I don't use or trust cheap-o power strips, at all, anywhere.
So don't get "cheap-o power strips". I use name brand suppressors with
high ratings.

UL1449 has, since 1998, required thermal discoinnects for overheating
MOVs. If a suppressor is UL1449 listed there is not much probability of
any problem. The author of the NIST guide has written "In fact, the
major cause of [surge suppressor] failures is a temporary overvoltage,
rather than an unusually large surge". TOV is, for example, a
distribution wire falling onto the secondary wires that go to your house.
Again, if you really trust any UL markings on a power strip, go for it.

You do relized that UL doesn't even test most stuff, they sell stickers.
That's the business model. If you want to get more technical, they're
really a licensing company.

Complete nonsense.

In Europe equipment is mostly self-certified that it meets a standard.

UL tests almost all equipment it lists.
http://en.wikipedia.org/wiki/Underwriters_Laboratories
"the UL Mark requires independent third-party certification from UL"

Some equipment, like TVs are tested to fail safely - it is not practical
to test whether they work.

Much of the UL listed equipment - fuses, circuit breakers, switches, ...
- are tested to comply with a standard that requires ?fitness for a
given use? and ?service life?.Ordinary wall switches used in power
wiring are tested by UL to remain functional after 30,000 operations at
or above their current and voltage rating. (The test is a lot more
involved than that.)

For surge suppressors, under UL1449 suppressors are tested by UL for
let-through voltage under specified conditions followed by a series of
20 surges followed by a let-through voltage test again. If the second
let-through voltage dropped significantly the MOVs are deteriorating. A
suppressor has to be functional through all these tests. Further tests
are of a nature that the suppressor might fail. It must fail safely. As
in my last post, overheating MOVs must be disconnected safely.

Incidentally, I was the technical end of a UL panel shop.

they have nothing at all to do with safety, at all, any more than iso 9001
has anything to do with quality.

UL listing of electrical equipment has everything to do with safety.

It's possible you have some decent surge protectors, but you're 0.01% of
the market.

UL1449 listed suppressors have been tested to pass at least a minimum
floor of protection. Anyone can buy well known name brands and get
suppressors with high ratings like I do.

Francois Martzloff was the surge expert at the US-NIST and wrote the
NIST guide. He also has many published papers on surges. I have included
some of his information in previous posts.

In one of his papers Martzloff has written "in fact, the major cause of
[surge suppressor] failures is a temporary overvoltage, rather than an
unusually large surge". TOV is, for instance, a distribution wire
dropping onto the wires that go to your house. (This is, of course, not
a surge.)

Martzloff also suggests in the NIST guide that most equipment damage is
from high voltage between power and cable/phone wires. (This is
illustrated in the IEEE guide starting pdf page 40.)

The IEEE is the largest association of electrical and electronic
engineers in the US. The IEEE guide (a link was provided) was written by
the IEEE committee that covers surge protection devices. The IEEE guide
says plug-in suppressors are effective. The only 2 examples of
protection in the IEEE guide use plug-in suppressors.

Similarly, surge expert Martzloff says in the NIST guide (link provided)
that plug-in suppressors are effective.

Where is your source that says otherwise.

So, did martzloff test this item?

http://cpsc.gov/cpscpub/prerel/prhtml10/10184.html

The recall is for a power strip, which is not a surge suppressor.

It was tested by ETL - maybe a reason to not buy equipment that is not
tested by UL. Did ETL use the appropriate UL standard?

what about this, who tested these? they were wired with reverse polarity,
even a $3 outlet tester would have found that:

http://cpsc.gov/cpscpub/prerel/prhtml04/04573.html

Wow - a recall from 2004.
It also does not cover any surge related components. So what? Companies
can make dumb mistakes.

how about energizer branded products, were these tested:

http://cpsc.gov/cpscpub/prerel/prhtml04/04002.html

How devastating - a recall from 2003. Appears to be UPS parts, not surge
related parts.

The pictures of the case shows no UL label - a label should be visible.

That's just a random sampling.

Anecdotal evidence proves astrology and homeopathy work.

These products and pretty much anything
similar are the most poorly constructed and designed products ever made,
next to coffee pots that lack power switches.

I understand now. You are afraid of electricity. Avoid the nasty
electrical stuff - *any* of which may be recalled. Just move to the
country, use candles and outhouse and a horse. Maybe you could become Amish.

If you really expect some item that's about to burst into flames by just
being plugged in to protect anything when there's a power surge, you must
love living on the edge.

I don't expect any listed surge suppressor to burst into flames so I
guess I am not living on the edge.

UL listed suppressors made since 1998 have thermal disconnects to
disconnect overheating MOVs.

None of your horrifying links have anything to do with surge protection.

The 6 electrical engineers who actually know something about surge
protection and who have written 2 guides all say plug-in suppressors are
effective. They don't share your paranoia (but they aren't afraid of
electricity).

Where is your source that says plug-in suppressors are not effective?

And why does the IEEE guide use plug-in suppressors in the only 2
examples of surge protection?

 

[Jeffrey D Angus]

So, did martzloff test this item?

http://cpsc.gov/cpscpub/prerel/prhtml10/10184.html

ETL Certified.

http://cpsc.gov/cpscpub/prerel/prhtml04/04573.html

No listing of it on the Belkin home page, or in their
recall listings.

how about energizer branded products, were these tested:

http://cpsc.gov/cpscpub/prerel/prhtml04/04002.html

Canadian UL

So, what point were trying to make about UL ?

Jeff

 

[bud--]

Which is what UL testing does. It tests for human safety. Does a
protector have to be working after all tests? No.

westom (aka w_tom) is a well known internet nut on a religious crusade
to eliminate the scourge of plug-in suppressors. He is here because he
uses google groups to look for "surge".

As I said previously (and westom conveniently did not include), UL
requires that suppressors - plug-in and service panel - be fully
functional after a series of 20 test surges. They can fail only during
later tests that determine they fail safely.

So does a suppressor have to be working after *all* the tests? No. The
later tests are intended to cause failure.

Does it have to successfully suppress the test surges and remain fully
functional? Yes.

And still UL Listed protector were causing house fires. So now we
have UL 1449 3rd edition. More attempts to keep undersized protectors
from causing house fires.

In westom's mind plug-in suppressors have minuscule ratings and service
panel suppressors have mega-ratings.

In fact:
- UL listed suppressors have been tested to provide at least a floor
level of protection.
- As I said previously, the amount of energy absorbed in a MOV in a
plug-in suppressor is surprisingly small, even with a very strong strike
to a utility pole behind a house (information from Martzloff technical
papers).
- Plug-in suppressors with very high ratings are readily and cheaply
available.

UL standards are constantly changing. Where is the massive record of
house fires?

Better is to earth a properly sized protector so that even direct
lightning strikes do not cause protector failure.

westom's objection to plug-in suppressors is really based on his belief
that all protection must directly involve earthing the surge. Since
plug-in suppressors protect primarily by clamping, not earthing, westom
cannot figure out how they work. Perhaps because his earthing belief
makes him look like even more of a nut, it is almost nonexistent in this
thread.

Do plug-in protectors do effective surge protection? Even the cited
Dr Martzloff says no.

What does Martzloff really say about plug-in suppressors?
Read what he wrote in the NIST surge guide:
They are "the easiest solution".
And "one effective solution is to have the consumer install" a multiport
plug-in suppressor.

Plug-in protectors, in some cases can
contribute to nearby appliance damage which is what bud's IEEE
brochure shows on page 42 Figure 8:
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf
It shows a nearby protector (located too far from earth ground)
earthing a surge 8000 volts destructively through a nearby TV.

If poor westom could only read and think he could discover what the IEEE
surge guide says in this example:

- A plug-in suppressor protects the TV connected to it.
- "To protect TV2, a second multiport protector located at TV2 is required."
- In the example a surge comes in on a cable service with the ground
wire from cable entry ground block to the ground at the power service
that is far too long. In that case the IEEE guide says "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector."
- westom's favored power service suppressor would provide absolutely NO
protection.

It is simply a lie that the plug-in suppressor in the IEEE example
damages the second TV.

From Dr Martzloff's 1994 IEEE paper on plug-in (point of connection)
protectors - his first conclusion says a protector can even contribute
to nearby appliance damage:

westom forgets to mention that Martzloff said in the same paper:
"Mitigation of the threat can take many forms. One solution illustrated
in this paper, is the insertion of a properly designed [multiport
plug-in surge suppressor]."

At the time of the paper, 1994, multiport surge suppressors (including
ports for phone and cable) were just a concept or very new. The whole
point of his paper was that multiport suppressors were effective
protecting, for example, TVs with both power and cable connection.

On alt.engineering.electrical, westom similarly misconstrued the views
of Arshad Mansoor, a Martzloff coauthor, and provoked a response from an
electrical engineer:
"I found it particularly funny that he mentioned a paper by Dr. Mansoor.
I can assure you that he supports the use of [multiport] plug-in
protectors. Heck, he just sits down the hall from me. LOL."

Trying to twist sources to say the opposite of what they really say is a
favorite tactic.

What do informed homeowners do so that plug-in protectors do not
cause house fires? Earth one 'whole house' protector.

A service panel suppressor is a good idea.
But again quoting from NIST surge guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

A service panel suppressor does not limit the voltage between power and
cable/phone wires, which the NIST surge guide suggests is the cause of
most equipment damage.


For real science read the IEEE and NIST guides to surge protection. Both
say plug-in suppressors are effective.

Then read the sources that agree with westom that plug-in suppressors
are NOT effective - there are none.

Simple questions that have never been answered:
- Why do the only 2 examples of protection in the IEEE guide use plug-in
suppressors?
- Why does the NIST guide says plug-in suppressors are "the easiest
solution"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?

 

[GregS]

westom (aka w_tom) is a well known internet nut on a religious crusade
to eliminate the scourge of plug-in suppressors. He is here because he
uses google groups to look for "surge".

As I said previously (and westom conveniently did not include), UL
requires that suppressors - plug-in and service panel - be fully
functional after a series of 20 test surges. They can fail only during
later tests that determine they fail safely.

I have been thinking of putting a main surpressor in the breaker box.
When I moved in the power company said there was one
installed in the meter, and if I wanted to continue using
it it would cost so much per month. i didn't of course, but I wonder
if they really took it out. ??

I put a couple in in the old house on the telephone lines
to ground on the main wooden panel after I destroyed a modem.
Never had any know hits after that though.

just last week guy here said his surge surpressor exploded as a hit
happened outside the house. His TV still works.


greg

 

[bud--]

I have been thinking of putting a main surpressor in the breaker box.
When I moved in the power company said there was one
installed in the meter, and if I wanted to continue using
it it would cost so much per month. i didn't of course, but I wonder
if they really took it out. ??

The utility suppressors I have seen are between the meter and meter box
- there is a spacer between them.

I would rather have my own service panel suppressor. The IEEE surge
guide has advice for ratings and installation.

They solve many, but not all, surge problems. They are a particularly
good idea in high lightning areas.

I put a couple in in the old house on the telephone lines
to ground on the main wooden panel after I destroyed a modem.
Never had any know hits after that though.

As I have said several times, the NIST surge guide suggests that most
equipment damage is likely caused by high voltage between power and
phone/cable wires.

In the US, telephone companies are almost always very good about
installing an entrance protector that clamps the voltage on the phone
wires to a ground terminal. The ground terminal needs to connect with a
short wire to the ground at the electrical service. With a large surge
the house ground can rise thousands of volts above absolute ground. You
want all wiring - power, phone, cable, satellite - to rise together.
This is stressed in the IEEE surge protection guide - very good
information. A cable entry ground block also has to connect with a short
wire - cable companies are not nearly as good as phone companies doing
this right. And satellite entry ground blocks also have to connect to
the power grounding system. Satellite installations can be even worse.

As I said previously, if you use a plug-in suppressor all external wires
to a set of protected equipment need to go through the suppressor -
power, phone, cable, .... This prevents high voltage between the wires
to the protected equipment.

 

[GregS]

The utility suppressors I have seen are between the meter and meter box
- there is a spacer between them.

I would rather have my own service panel suppressor. The IEEE surge
guide has advice for ratings and installation.

They solve many, but not all, surge problems. They are a particularly
good idea in high lightning areas.


As I have said several times, the NIST surge guide suggests that most
equipment damage is likely caused by high voltage between power and
phone/cable wires.

In the US, telephone companies are almost always very good about
installing an entrance protector that clamps the voltage on the phone
wires to a ground terminal. The ground terminal needs to connect with a
short wire to the ground at the electrical service. With a large surge
the house ground can rise thousands of volts above absolute ground. You
want all wiring - power, phone, cable, satellite - to rise together.
This is stressed in the IEEE surge protection guide - very good
information. A cable entry ground block also has to connect with a short
wire - cable companies are not nearly as good as phone companies doing
this right. And satellite entry ground blocks also have to connect to
the power grounding system. Satellite installations can be even worse.

As I said previously, if you use a plug-in suppressor all external wires
to a set of protected equipment need to go through the suppressor -
power, phone, cable, .... This prevents high voltage between the wires
to the protected equipment.

I have to recheck my cable for ground. I still have a telephone to the house unused,
and an old unused Comcast phone box unused. Also the battery power
supply backup which I am going to use for my house emergency
lighting.

I just checked, and its difficult to find surpressors that are cheap.
I found one for $30 and might get a discounted price.
This is a basic model..................
http://www.grainger.com/Grainger/items/1ECD1?Pid=search

greg

 

[GregS]

I have to recheck my cable for ground. I still have a telephone to the house
unused,
and an old unused Comcast phone box unused. Also the battery power
supply backup which I am going to use for my house emergency
lighting.

I just checked, and its difficult to find surpressors that are cheap.
I found one for $30 and might get a discounted price.
This is a basic model..................
http://www.grainger.com/Grainger/items/1ECD1?Pid=search

I always thought local surpressors were good to protect from motorized equipment
and keep things common mode and to ground.

I might have a lack of available breakers, and I am thinking I
allready have an outlet near the box on one 120 side. i might put in another outlet on the other
120 side and use plug in replacable MOV's. I don't see much difference in
using separate breakers vs protecting lines allready in use.

greg