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Dangers Of Electrical Storms

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mine stays plugged in 24/7 even during storms. i'm safe.

btw. surge protectors are a f'ing joke. you need a uninterruptable power supply that regulates the power to make any attempt at stopping lightning strikes.

Yeah, that's my strategy. The plug actually helps ground your computer (actually the metal cage grounds it as well). Though you run the risk of a power-surge, I'd rather make sure my electrical eq is grounded adequately during a lightning storm, then ungrounded.

An uninterpretable power supply should be standard equipment anyway.
 
A few years back, I was out of town on a trip, my roommate at the time, was using my Stereo and TV. I had a router hooked up, my computer, fish tank, etc.

A bolt hit my house, fried the Stereo Receiver, sent a bolt of electricity out of the front and into a wall across the room. (according to my roommate.), Fried a fish tank (Fish were okay.) Took out the router, and busted a hole in the roof so it started leaking on my pool table. Not even joking......
 
well there was a t-storm and I was working on my desktop and laptop. The desktop was pluged into a surge protector and the laptop was not. Then Boom lighting hits power goes out for like 60 seconds. AND guess what the desktop is now fried. but the laptop is perfictly fine :bang head and :facepalm:
 
Luck, perhaps, or its power brick has a better transient filter+TVS setup, or maybe the laptop has one and the brick does.
If the Strider 500w was the PSU in question, it lacks a TVS diode for surge suppression. It may be that your strip was degraded, or that it simply couldn't take the spike, and the PSU lacked internal protection while the laptop power brick did not.
 
Ahh. That's probably why it died. OEMs don't generally spend a lot of excess money on PSUs. Did it have a little voltage switch next to the power cord?
 
Some of you undoubtedly know this, but I feel that it needs to be said given some of the posts in this thread: A UPS will not offer significant protection against a lightning strike.

I understand the mistake since people understand that a UPS will switch over to batteries if the line voltage drops too low or in better units also if it rises too high. That switch action, however, takes milliseconds to trigger. Meanwhile, in the first few hundred microseconds, the voltage spike has already done its damage. UPS units themselves typically offer some, albeit extremely limited, surge suppression. A high end unit like a SmartUPS 2200 might offer 480 joules worth of absorption capability, and it's most likely just through a MOV. MOVs are not the fastest to react devices and they degrade over time as they absorb energy.

If someone cares about the equipment within their home, I would suggest the following:
- Spark gap arrestor before the main breaker, on your cable drop, and on your phone line if present. Phone lines should always have a spark gap at least within the US, but your cable line likely does not.
- Either whole-house surge suppression before the main breaker or quality suppression on each outlet where you care about what is connected
- Surge suppressor on both phone and cable, ideally before any distribution within your home
- Any suppressors used should ideally have multiple kinds of protection elements such as TVS diodes (never wear out, limited capacity, react in nanoseconds), MOVs (wear out over time, moderate capacity, react in microseconds), and gas tubes (never wear out, high capacity, react in milliseconds) and also offer protection between each conductor instead of just hot to ground. Your surge may not come in on the hot wire.

It's also important to make sure that if you're going to protect a device that it's fully protected. Many people make the mistake of putting their computer on a surge suppressor but then leaving the Ethernet connection unprotected. I can't tell you how many times I've seen charred Ethernet adapters with destroyed inductors, traces, and controller ICs that inadvertently saved the machine in question. Many others are not so lucky. This can happen quite easily in a common scenario like this: A user has a desktop and a cable Internet connection. They have their cable modem/router and desktop both plugged into surge suppressors but not the incoming cable feed itself. A surge can come in on the cable connection and fry not just the router but potentially the desktop as well since they're connected together, unprotected, over Ethernet.

Whole house surge protection is available from many power companies for a small monthly fee of like $5-10. If the device gets hit, most power companies will replace it for free. Additionally, it's worth noting that if you don't protect everything (and unfortunately, even if you do), you are susceptible to a nasty spike crossing from an unprotected line to a protected line if given an opportunity. You might find that your unprotected power drop in a wall allowed an avenue for your protected Ethernet setup to have a spike induced on it.

In the end, no device will ensure you don't lose equipment. All you can do is take reasonable precautions to protect yourself. For most people, unplugging everything in their home before every storm isn't a reasonable option. It also doesn't help much as a strategy if you're at work or traveling when the surge hits. Even actions as simple as the power company throwing a distribution switch can cause a voltage spike, and the weather forecast won't help you there.
 
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The rackmount UPSes do offer very good protection against surges and can be had for cheap used, though you'll need new batteries for them.

One of the best tips I have found for protecting a cable line is to use a piece of wire (14 gauge or bigger, as short as possible) to connect the outside of the line (use hose clamps) to chassis ground (one of the screws holding the PSU or a metal cased surge protector). Beware that some surge protectors can degrade signal quality, so make sure you can return it if it causes problems.

If you know some electronics, bypassing the "soft ground" caps on Ethernet interfaces greatly helps them withstand surges and even ESD, but that would void your warranty.
 
There's a cap connecting the line side of the Ethernet connection to ground. Not too sure what was the intent but it's clearly a very flawed design. The fix is to just short that cap.
 
Please do not do that. Ethernet lines are floated (that is what the inductors are for) so that differences in ground potential do not cause large voltage differentials or component damage. This also provides a large amount of isolation between the physical communication bus and the signal on the card being that the isolation is provided via inductance (transformers). Inside your house this may not be much of a problem, but if you were to run Ethernet between buildings or even across single large complexes like in a business, you can end up with a dangerous situation where the ground potential is enough different to cause communication problems, component damage, or worse.

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As for rackmount UPSes providing good protection, I'll have to disagree. 500 joules is less than you get on any but the cheapest of power strips.
 
The rackmount units are generally double conversion designs (the older ones, at least). With that design, a large surge might damage the unit itself but the load would be pretty well isolated.

The problem with the caps is that they do not provide a path for static buildup to dissipate. At one point, some cards had 1M resistors across the caps but then someone thought it was "unnecessary" and decided to remove it. You can add a resistor and/or MOV rather than just shorting the cap.
 
Double conversion units are available, but they're quite a bit more expensive. Most units (rackmount or not) from reputable companies in the <= $1000 price class are still switchers. In any case, I'd much rather consider a $25 surge protector like a TrippLite Ultrablok to be expendable than a $500-1000 UPS. To me, the UPS equipment itself is valuable enough to be worth protecting.
 
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