doesn't this defeat the purpose of having a surge protector?

If a big enough storm comes along, your surge protector won't do much.

Its for brown-outs, surges and other pesky electrical problems.

To unplug during storms is the only safe and reliable protection.

Timothy

You're more in dange from a dip in power. I lost a computer WHen I was living in NJ becasue of constant dips in power. I was living in a very rural area with uneven service.

Now ,if I am not going to bu using it or am away from home, I unplug. I can't shake the paranoia :)

A UPS (uninterruptible power supply) is essentially a battery and an AC converter. It will keep your computer running during a brown-out, or a momentary loss of power. You can buy them in various sizes, and depending on how much power your computer gulps, the size of the battery, the age of the battery, and whether power is low, or out, your computer can continue to run for some minutes to a good part of an hour in a blackout, and could go all day in a brown out. UPSes, incidentally, are also excellent surge protectors because the battery itself can soak up a large surge.

Laptops, of course, do not need a UPS. Their battery serves as a built-in UPS.

A surge protector is just a hair-trigger circuit breaker. If a voltage spike comes down the line, it is supposed to cut out before the voltage spike can damage anything connected to the surge protector. Generally, they do that quite well.

One situation in which a surge protector may fail is a direct lightening hit to the wiring in your dwelling. I had the unfortunate experience of having this happen to me once, back in the 1970s. Lightening hit the wires just outside my apartment. It blew out every light bulb and appliance except the stove and refrigerator, and most of them were turned off at the time. The voltage surge was so high it tripped all the circuit breakers, but first jumped across all the open switches and still had enough oomph to melt all the filaments in the light bulbs. I think the only reason the stove survived is that it was designed for 220V, and the electronics were heavy-duty enough that the surge didn't last long enough to melt it.

That was a really extraordinary event. If you want to be really safe, you should unplug everything during a thunder storm.

I don't care to be that safe. It's simply more trouble than it is worth to me, for the size of the risk. I don't unplug anything, nor do I turn anything off, and I lived in the midwest for a long time, which can get serious thunder storms. I use surge protectors for my valuable electronics, and if a direct hit happens, I'll just eat the loss. BTW, if lightening takes out your computer, chances are good the disk drive is still mechanically OK, and the data can be retrieved, though if the motor was fried, that might be expensive. To me, the data is more important than the actual cost of the computer.

Even unplugging things is not an absolute guarantee of protection. The lightening could hit your dwelling and set it on fire. Very highly unlikely, but it happens. Or the storm could spawn a tornado. You can't eliminate all risk. You just decide which risks to counteract, and which to ignore. For people along the Wasatch Front, earthquake is an acceptable risk. If it were not, we shouldn't be here.

What is the advantage if I turn it off (not unplug it) during a storm?

What is the advantage if I don't turn it off during a storm?

Depending on how good it is, it can protect against spikes in power.

Nothing will protect against a direct lightning strike, but most spikes are much smaller than that.

Too many electrons can fry your stuff (spike).
Too few electrons can fry motors especially (brown out).

In a bad storm, we unplug the protectors.



Edited 1 time(s). Last edit at 06/24/2011 01:36PM by Heresy.

The answer is not as simple as yes or no.

Generally speaking, a device plugged into a surge suppressor is protected from voltage spikes. This protection is provided by a filter circuit consisting of inductors, capacitors, and metal-oxide varisters (MOV). The MOV is a component who's resistance varies with the voltage across it. For lower voltages, it's resistance is very high. As the voltage increases, there comes a point where it's resistance drops dramatically. These devices are placed across the power lines inside the suppressor so that any voltage spike in excess of the trigger voltage is shorted. This keeps the surge from reaching the devices plugged into the surge suppressor. Surge suppressors are rated in the number of Joules of energy they are designed to absorb without being damaged.

Turning the surge suppressor off added another layer of protection by creating an open circuit between the power coming into the suppressor and the circuitry inside it. This will generally increase the protection of the devices plugged into the suppressor but not completely. If enough voltage is applied it can arc across the open switch and into the attached devices. The same is true of the devices plugged into the suppressor. If they are turned off they are protected by the open circuit of their switch. However, a large enough voltage spike can arc across the switch and cause damage.

Here are the levels of protection in ascending order.
1. Device plugged into a surge suppressor that is turned on.
2. Device plugged into a surge suppressor that is turned off.
3. Device plugged into a surge suppressor that is unplugged.
4. Device unplugged.
5. Device unplugged and wrapped in a conductive material like aluminum foil.

Uninterruptible Power Supplies (UPS) add another level of protection by protecting your devices from low voltages or voltage sags in addition to voltage surges.

Additional reading:
http://en.wikipedia.org/wiki/Varistor

I believe those nuclear reactors in Japan were designed to withstand a 7.6 which doesn't do much good when a near 9.0 hits.

Just sayin'

Timothy

And had the tsunami not destroyed the diesel generators for the emergency cooling system they would probably be back in operation today.

Just sayin'

The system failed.

What else can I say?

Timothy

The point I was trying to make was that the damage to the Fukushima plant was caused by the TSUNAMI, not the earthquake itself. The plant survived the 9.0 earthquake even though it was designed for a 7.5 earthquake. The reactors shut down automatically at the first indication of the earthquake and the backup cooling system was working fine. It wasn't until the tsunami took out the backup generators that conditions at the plant went bad and then it took 9 hours after the backup generators quit until the battery power ran out.

Had the sea wall been able to withstand the tsunami or had the diesel generators been located on higher ground or the power lines between the plant and the rest of the power grid not collapsed, the plant would probably be back in operation today.

... surge protectors take care of the unexpected .. usually.

Unplugging a surge protector is the only guarantee that storms - which usually don't happen without advanced warning - won't damaged electronic devices should said disturbances make an unexpected direct hit.

Perhaps your house will burn down should that occur. Maybe your generators will fail because of excessive flood water. Point is, its better to be safe than sorry.

Fixed fortifications are monuments to the stupidity of man.

Timothy

I build my computers from junk parts, so that's not an issue. However I have a very expensive Technics piano that I worry about with a circuit board that can't be replaced. So, I plugged that sucker into a switched outlet. When I want to play it, I turn on the switch. When I'm done, I turn it off. That way I'm not worried about electrical hazards unless the breaker box is hit, and I can keep all the wires hidden.

I use a big ass server UPS (APC Back-UPS 1100) for my plasma TV and HTPC, and I've been amazed at how well that works. If I don't have power, I just watch a movie. :)

...how long does it last before you have to replace it?

Most UPSs have a test button.

Side benefit of a UPS - if there are abandoned bicycles in your building's bike rack (happens all the time when students graduate) you can connect a Dremel-like tool to the UPS, take it outside, and use a cutting disk to remove the bike cable.

My lack of worry about unplugging stuff is because I was in charge of maintaining and replacing desktop computers in a building that had 250 computers, very few surge protectors, and almost no UPSes except for mine, and the laptops. We never lost a computer to a power spike, nor a burnout from under power, over a ten year period.

We did lose computers to bad capacitors, bad hard drives (one shipment of 30 computers had a 55% hard drive failure rate over their 4 year lifetime). There was also minor theft and vandalism. Most commonly stolen item: mouse balls. I kid you not. WTF? Maybe people took them out to clean them, and just lost/dropped the things. Memory, network cards, and one graphics card got stolen. We did lock our cases shut, but that was not foolproof.

Power flickers did cause all the computers to reboot, though I hardly ever noticed, what with me having a UPS and all. I bought it myself. The rest of the faculty was too cheap.

And twice a year I went out and used my UPS to cut bikes loose that hadn't moved from the rack in 6 months and turned them in to Security. Somebody got some cheap transportation at the abandoned property sales. :)



Edited 1 time(s). Last edit at 06/24/2011 07:24PM by Brother Of Jerry.

We lost a server at work due to a lightening strike on the phone wire. Apparently it jumped the lightening protector (arced over) and fried the panel!

Similar thing happened at the home we used to live in. The phone cables had been put in in the early 1950s, and the lightening protector failed and I awoke to the sound of the modem board in the computer going: "pop, crackle, crackle!"

Fried the board, so I got a USB modem, instead, which worked much better.

Because I didn't turn off the UPS and power supply 3:00 a.m. last night, DH was ticked at me. He crabbed at me for a good 15 minutes. I could not calm him down.

We had a horrible lighting storm very close to the house. It remained in the area for 2.5 hours. It was a very slow-moving storm.

I was afraid for my family. What I did was got dressed in street clothes in case we had to leave the house. I located all the medications for the same reason. I made sure everyone was OK through the storm. I let DH sleep rather than waking him up. I stayed up and walking/sitting and caring about my family from 2:30 when the storm began until it sufficiently passed around 5:00 a.m.

DH didn't want to hear any of the above. All he cared about was the fact that I did not turn off a power supply and a UPS in the den.

I have been miserable all day long. I have been crying on and off all day long.

I feel useless despite being the one on guard for a few hours in the middle of the night. :-(

Sorry your husband is being a jerk.

Unless lightning hits your house or a power pole extremely close to your house it shouldn't make it through a UPS and even if it does, most UPSs come with as much as $50,000 in insurance against damage caused by power surges to any equipment plugged into the UPS.

The entire power distribution grid is designed to protect against lightning strikes. Power poles, even wooden ones, are grounded. They have grounding wires running from the top of the pole down into the ground to carry lightning strikes away.

The box where the power enters your house should be grounded and telephone and cable TV should be grounded where it enters the house as well.

Even with all this grounding, sometimes lightning can propagate down a power, telephone, or cable TV wire and enter the home. There is where surge protectors and UPSs come into play. They're the last line of defense.

Next time a storm comes through your area, maybe you should wake your husband up and let him stay up and deal with it and you go to bed. That way it can all get done the way he wants it done.

This is the husband that I have to caution about being on his computer when we have lightening storms. Sometimes he will shut it down, other times he will continue to play. I don't get it.

Thanks for your reply.

Grumpy's wife,
Pixie

Oh, Pixie!!! Your husband is a grumpy idiot. You should design and make him a special Grumpy Idiot hat he can wear when he feels his grumpy idiocy mood coming on. Then people would know when to avoid him! ;oD

two thirds of it. I am assuming that the roof must leak, and we have more rain scheduled for next week. I have no idea if their home was hit by lightening.

"Grumpy" is in the den with the door closed. I think I'll go to be while the house is quiet.

Thank, again, Matt. Your post made me smile!

Pixie Dust Wrote:
-------------------------------------------------------
> two thirds of it. I am assuming that the roof
> must leak, and we have more rain scheduled for
> next week. I have no idea if their home was hit
> by lightening.
>
> "Grumpy" is in the den with the door closed. I
> think I'll go to be while the house is quiet.
>
> Thank, again, Matt. Your post made me smile!

I am glad to hear that!

My wife reminds me of your husband. Maybe they BOTH need Grumpy Idiot hats! ;oD