What about thunderstorms?

[BernieRay]

No need to Bill, as an engineer with over 30 years experience in the power industry I can easily recognize his stuff for what it is -- mostly gibberish.

He raises a few good points -- a properly grounded whole house surge protector is indeed the better protection, he fails miserably in his statements that its the only protection, as well as in his statements that it is complete protection.
In addition his "engineering" of the dynamics of a surge (he erroneously seems to believe that lightning is the only thing that can cause a surge) and in particular lightning induced surges is, shall we say, from somewhere out beyond left field.

I suspect he also is extremely ignorant of US building codes -- residential, commercial and utility.

There's a post that everyone can agree with - silence!

[billbolton]

I suspect he also is extremely ignorant of US building codes -- residential, commercial and utility.

The same seems to apply to the Standards Australia wiring rules!

Other aliases to watch for are "westom1", "w_tom" and "w_tom1".

Cheers,

Bill

[Axollajeake]

gucci sunglasses

[archangle]

Well, I am putting a whole house surge protector on my "round tuit" list. It is a good idea.

The individual surge suppressors still stay on the CPAP and other vulnerable/valuable equipment.

[marl64]

I thought about this post last night when the power went off shortly before bedtime. I thought I was going to get a break, I mean have to do without my CPAP. Since the tornado sirens were going off all evening I didn't manage to get to bed until late and the power had already returned by then. It's storming again tonight but the power is still on.....so far!

[westom]

Electricity won't pass that "2cm gap" when it has a much easier path to ground (the 3rd prong).

Add numbers to your assumption. Let's say a trivial 100 amp surge is incoming to an appliance and protector. So that current will go back to a breaker box earth ground? 'Impedance' has been repeated often. Some numbers.

A 12 AWG ground wire maybe 50 feet back to the breaker box is less than 0.2 ohms resistance. And something like 120 ohm impedance. 100 amps times 120 ohms is something less than 12,000 volts. How does that current get back to a breaker box? It doesn't. It goes hunting for earth destructively via any nearby appliances. That appliance need not even be connected to the protector.

An NIST brochure puts numbers to this. That current is earthed 8000 volts destructively through a nearby TV. How is that protection?

Second, once that surge is all but invited inside, then nothing - especially not plug-in protectors - can 'block' or 'absorb' a surge. That is what an adjacent protector must do - either 'block' or 'absorb' that current. It can't.

Third, even open circuit breakers do not stop surges. Will a millimeters gap in a breaker, fuse, or switchl stop what 3 kilometers cannot? Of course not. Those are damning numbers.

Furthermore, circuit breakers take milliseconds or seconds to trip. Easily 300 consecutive surges could pass through that breaker or protector before any switch or fuse even thought about tripping. Nothing 'blocks' a surge. As in nothing. As made obvious by another term - current source.

A facility that cannot have damage always has a low impedance (ie less than 3 meters) connection to earth. So that a surge is nowhere inside. That is how protection from direct lightning strikes has been done over 100 years ago.

Fourth, failing protectors never do protection. Remember how electricity works. If a surge is incoming to that protector, then at the same time, that same current is outgoing into attached appliances. That current exists simultaneously everywhere in a path from a cloud, through the house, and maybe 4 kilometers through earth. Much later, something fails in that path. Nothing as in nothing blocks or stops that current. Effective protector with a low impedance connection to earth never tries to be so foolish.

Grossly undersizing a plug-in protector creates a "it failed to protect my CPAP" myth. A surge too tiny to overwhelm protection already inside a CPAP easily destroys that near zero joules protector. Then naive consumers recommend that ineffective and obscenely profitable device. Grossly undersizing a protector gets naive consumers to recommend it and buy more.

Informed consumers spend $1 per appliance for a 'whole house' protector (ie rated 50,000 amps). Then nobody even knew a surge existed. Even a protector is not damaged. Then protection remains functional for decades. Then one need not buy a new plug-in protector every year or so - and so many myths recommend.

Nothing useful is gains by an undersized (plug-in) protector. Again, how many joules does your's claim to absorb?

Grossly undersizing to create failures increases profits. Meanwhile, its fire risk is so great that cruise ships may confiscate that protector. Fire from near zero joules protectors is another major problem with protectors designed to fail on a surge.

What did that youtube video note?
https://www.youtube.com/watch?v=JvGw58w4rxg
Plug-in protectors do not provide effective protection without a 'whole house' protector. A 'whole house' solution is required to even protect plug-in protectors. The 'whole house' solution does 99.5% to 99.9% of the protection. Then plug-in protectors might do an additional 0.2%.

Did we mention the 15 million APC protectors now known to be so dangerous as to be removed immediately? And still some recommend these near zero protectors because advertising and another's insults said so.

[palerider]

note to future readers:
best to ignore westom, he has a very superficial understanding of electrical principles and digs up years old threads to argue with people that aren't here any longer.

best to put him on the foe (ignore) list.... certainly don't make the mistake of responding to him.

"trivial 100 amp surge is incoming"

[westom]

He raises a few good points -- a properly grounded whole house surge protector is indeed the better protection, he fails miserably in his statements that its the only protection, as well as in his statements that it is complete protection.

Please read what I said. 'Whole house' protection is a 'secondary' protection layer. Go back. Each layer of protection is defined by an item that absorbs energy - earth ground. I never said the 'secondary' protection layer is sufficient. Read a discussion about the 'primary' protection layer.

I also did not say it is 100% protection. Even provided IEEE numbers. It does 99.5% to 99.9% of protection. More numbers define what that means to a consumer.

Plug-in protectors were also defined effective - for about 0.2% of protection. As the above youtube video says, those must exist with a 'whole house' solution to be effective.

Nobody said lightning is the only surge. Again, please read what was written. Other surges sources include stray cars, tree rodents, utility switching, and linemen errors. In one case, 33,000 volts line fell on local distribution. Electric meters literally explode 30 feet from their pans - in pieces. So many had appliance damage. Fortunately no plug-in protectors caused a fire. But some had failed circuit breakers.

My friend knows someone who knows this stuff. He had a properly earthed 'whole house' protector. His meter disintegrated. But nothing else was damaged - not even that properly sized and earthed protector. Just another example of why informed consumers always earth a 'whole house' protector.

Protect from lightning is to have protection from all types of surges. Was doing this stuff over 40 years ago - long before PCs existed. With significant experience including tracing surges to explain to a design review why unacceptable damage happened. For example, a surge earthed destructively through a network of powered off computers by plug-in protectors not used with a 'whole house' solution.

What do building codes have to do about this? Question was protection for un-grounded circuits. A least expensive solution is also a best solution. Nobody even need rewire the house as some foolishly recommended.

How to have protection on un-grounded circuits? A properly earthed 'whole house' protector.

Please read what I wrote - with numbers - before criticizing me for something I did not say.

[SewTired]

To the original poster: In the summer, I leave my Cpap unplugged on days I know I'm not going to be home and do unplug prior to arrival of thunderstorms. At night, the thunder is going to wake me ANYWAY, so I unplug the unit until the storm passes. I also unplug computers and TVs (power strip makes it easy - unplug a bunch of things at once).

We had lightning hit the street in front of our house once, shaking the house. While it wasn't obvious at first, the TV and computers that were plugged in started to have errors and weird problems over the next few months - had to replace circuit boards before they worked again.

So, my answer is unplug the stuff. It's free and you won't have to replace all your stuff if your 'protector' doesn't work.

[palerider]

To the original poster:

seriously? you reply to a post from Mar 15, 2011, to a poster that hasn't logged in since Feb 03, 2012?

[D.H.]

Use a good surge suppressor if you're worried about that. If it says not for medical equipment, they put that so that you won't be able to successfully sue them of something goes wrong (use it anyhow).