Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Lightning Strikes distrying HUBs and NICs

Status
Not open for further replies.

DougP

MIS
Dec 13, 1999
5,985
US
We have an old building.<br>We have UPS' on every PC and Server and HUB for AC power but nothing for UTP with RJ-45's<br>It's one story building and living in the lightning capital of the world &quot;West Coast Florida&quot; we get our share of hits.<br>Once in a while I'll come in Monday morning only to find serveral people cannot get on the network.<br><br>I troubeshot down to 2 HUB's located in differnt parts of the building and 2 NIC's. They are 3-Com so they are replaced under a lifetime warranty.<br><br>I have ordered a ton of APC PNET4 PROTECTNET 4 LINE ETHERNET boxes.<br>But can we do anything else? <br>Lightning Rods on the roof?<br>I understand that when PNET4's take a hit they have to be replaced as well. <p>DougP<br><a href=mailto: dposton@universal1.com> dposton@universal1.com</a><br><a href= > </a><br> Ask me how Bar-codes can help you be more productive.
 
I have a question, how is the lightning getting onto your network? Do you have some sort of external connection to the internet, perhaps ISDN?<br><br>Where I worked last summer, there was an incredible lightning storm, and we had a lightning strike which came in on our isdn line and fried a few network cards and really hit the server good.<br><br>Lightning rods may help, just make sure that the are well grounded! Being in Florida you may have companies down there specializing in lighting protection, I would like into that as they will be able to give you a better idea of how to protect yourself.<br><br>I am from Northern Ontario in Canada and we don't get many lightning storms up here :) just a big one every other year or so....<br><br> <p> fenris<br><a href=mailto:fenris@hotmail.com>fenris@hotmail.com</a><br><a href= > </a><br>
 
We have a DSL line. But nothing from that side was damaged.<br>It's connected directly to a Member server and the Member server is then connected to the Network. The member server has a firewall program on it. None of that was damaged at all. We have a T1 line too for phones only no Internet. Nothing happened to any of that either.<br><br>The damage was random around the building. We have a flat metal roof covered by black TAR. Par for the course here in Florida. So the roof is supported by huge Steel beams. And the Network wires are just laid in the beams. <br><br>This has been going on for ever before we had the new NT servers. We had Novell and just 5 or 6 PCs which had similar problems. The accountants who were the people responsible for the PC's at that time said that lightning fried the whole PC on several occasions. I don't know if that was the case or just a BAD NIC.<br>So they started using the PNET4's. That’s where I found out about them.<br>I have had these 5 NT servers running for 2-1/2 years without any problems. <br>&nbsp;<br>I did not use the PNET4's either since there were only 2 of them I need 30 some odd now. And I did not know if they would work on 100base-T since the old Novell was 10base.<br>Also none of the old wiring was used either I ran all new CAT5 wiring so I thought that old problem went away until yesterday. We had some major storms here over the weekend. They are monsoon's lasting days. Flooding out everything and lightning strikes by the thousands.&nbsp;&nbsp;Now a total 4 3Com SuperStack Hubs are bad.&nbsp;&nbsp;I found 2 more ports on 2 different hubs are not working today.<br><br>Lightning here is devastating here killing 3-4 people every year and destroying TV’s, VCR’s, and Refrigerators believe it or not. Any time you by appliances here they ask you if you want the extended warranty which covers lightning damage now.<br><br> <p>DougP<br><a href=mailto: dposton@universal1.com> dposton@universal1.com</a><br><a href= > </a><br> Ask me how Bar-codes can help you be more productive.
 
Any type of protection that actually takes a hit will have to be replaced.&nbsp;&nbsp;<br><br>Basically, about all you can do is go nuts and protect every single path into every computer.&nbsp;&nbsp;If you use modems, put protectors on the phone lines.&nbsp;&nbsp;If the PCs are on UPSes make sure the monitor power cord is protected as well.&nbsp;&nbsp;If you have dedicated printers, protect the power cord or the parallel port on the computer.&nbsp;&nbsp;Look at every wire in and out of every device and isolate it somehow.&nbsp;&nbsp;Lightning can jump in and out of devices through any available path.<br><br>Keep in mind that any protection is limited.&nbsp;&nbsp;I don't care what kind of guarantee the protector maker gives.&nbsp;&nbsp;Think anbout it, the bolt that just zapped you had enough potential to make a spark jump a mile or more from the cloud to ground.&nbsp;&nbsp;If it can jump that far it can certainly jump a few millionths of an inch inside a transistor. <p> Jeff<br><a href=mailto: masterracker@hotmail.com> masterracker@hotmail.com</a><br><a href= > </a><br> Of all the things I've lost in life, I miss my mind the most ...
 
Where I worked it came in through the isdn (we think) since only the network cards were damaged, except on the server which had a mobo and video card fried from the network card exploding(it literally melted). that network card was directly connected to the isdn router. <br><br>Like Jeff said, make sure every protal into your network is protected. Other then that there is not much you can do besides shutting down the network and unplugging it from the outside world ;)<br><br>From my understanding of line protectors(both phone and network) there is some loss of transmission speed through these devices.<br><br>I just thought of something, you might want to give a local isp a call and see what they do. They have to stay up for as long as possible to serve the customers.<br><br><br>That's my 2 cents.... <p> fenris<br><a href=mailto:fenris@hotmail.com>fenris@hotmail.com</a><br><a href= > </a><br>
 
&nbsp;&nbsp;&nbsp;&nbsp;We had similar problems with our mill and warehouse. These are &quot;shell buildings&quot; meaing that they were built with just a metal roof, metal beams, and a cement floor. We didn't even have to have a lighting strike, just a thunderstorm in the area would cause our equipment to blow. At one point, we lost 32 serial ports in 30 days. Some of the components had huge holes in them.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;What was happening was when the ground was getting wet the [electrical] ground was getting &quot;lost.&quot; (All the buildings are on red clay.) Since there was no ground, the buildings would act like giant capacitors. As soon as a circuit was activated with a ground . . . <b>ZAP!</b><br><br>&nbsp;&nbsp;&nbsp;&nbsp;There were two things that were done to fix the problem. First, we switched to fiber optics, esp. for runs betweens buildings and long runs in the buildings. The other thing that was done was to get a better ground connection. The phone company had to do this for their equipment since they were taking hits, too.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;We haven't had any problems since. The phone company sometimes still has problems, though.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;Your situation may be different but it sounds like your building is similar to our mill. Is it possible that your building may have lost its ground wire? Sometimes they rust off or get broken.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;Also are the cable runs &quot;double grounded?&quot; Experts who looked at our problem suggested that if both sides of a long cable run are grounded, the run acts like an antenna which can attract lightning.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;Just a couple of suggestion. Good luck. <p>James P. Cottingham<br><a href=mailto: > </a><br><a href= Veneer Co., Inc.</a><br>All opinions are mine alone and do not necessarily reflect those of my employer.
 
&gt;Also are the cable runs &quot;double grounded?&quot; Experts who looked at our problem suggested that if both sides of a long cable run are grounded, the run acts like an antenna which can attract lightning.<br><br><br>I didn't realize that! I will definately remember a good piece of info like that.<br><br>James, How deep did they place the grounds for each building and what type of ground did they use(stake, loop, etc.)?<br><br>I know up here a stake is recommended, but it is not feasible in some places as it is solid rock 1 inch below the surface. We use a large loop (6-7 feet in diameter)in these cases burried in the ground. It seems to do the trick.<br><br><br><br>&nbsp;&nbsp;&nbsp;&nbsp; <p> fenris<br><a href=mailto:fenris@hotmail.com>fenris@hotmail.com</a><br><a href= > </a><br>
 
&nbsp;&nbsp;&nbsp;&nbsp;In our case, the &quot;ground&quot; had to be pretty deep to get past the clay. I'm not certain how deep that was. Sorry. Looping the ground on bedrock would probably be best, alright.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;The fiber optic (FO) was our biggest help. Even if a piece of equipment does get zapped, the failure doesn't cascade down the line. In one case, a PC got zapped, which in turned zapped the hub, which in turn zapped the server. We haven't had a major failure from lightning since we put FO in. We even put some antennas on the roofs of the buildings (connected via FO) and they have not failed even through 3 hurricanes and innumerable thunderstorms! We took a direct hit to our computer room last year, the only problems were the monitors in the room were &quot;gaussed&quot; and our hair stood on end for awhile. :)<br> <p>James P. Cottingham<br><a href=mailto: > </a><br><a href= Veneer Co., Inc.</a><br>All opinions are mine alone and do not necessarily reflect those of my employer.
 
If you want the WEB site for APC here it is:<br><A HREF=" TARGET="_new"> make a option for any connector on the PC,<br>coax, RJ-45,DB-9 & DB-25 and RJ-11<br><br> <p>DougP<br><a href=mailto: dposton@universal1.com> dposton@universal1.com</a><br><a href= > </a><br> Ask me how Bar-codes can help you be more productive.
 
fenris,<br><br>The double grounding comment is interesting.&nbsp;&nbsp;We have a 100 pair cable buried for 1200' between two buildings. I've always kept the unused pairs grounded on one end to reduce crosstalk on the phone lines in use.&nbsp;&nbsp;I was told by a phone consultant that I should ground both ends for better lightning protection.&nbsp;&nbsp;&nbsp;Who to believe, eh?&nbsp;&nbsp;I guess it's flip a coin time. <p> Jeff<br><a href=mailto: masterracker@hotmail.com> masterracker@hotmail.com</a><br><a href= > </a><br> Of all the things I've lost in life, I miss my mind the most ...
 
&nbsp;&nbsp;&nbsp;&nbsp;Just goes to show you that a former EE teacher was right. He said, &quot;Antennas are magic. <b>Nobody</b> really knows how they work.&quot;<br><br>&nbsp;&nbsp;&nbsp;&nbsp;Point is, we tried single grounding, double grounding, and not grounding the cables, all with the same result. Our solution was to move to FO, but that may not be the best solution for you.<br> <p>James P. Cottingham<br><a href=mailto: > </a><br><a href= Veneer Co., Inc.</a><br>All opinions are mine alone and do not necessarily reflect those of my employer.
 
I had a similar experience when I was installing a high speed microwave link on an old building. Our radio gear was located in a NEMA enclosure on a roof and we ran outdoor CAT5 from radio gear to the switch. It layed on metal roofwork once it entered the building. Everytime we got a storm the radio and the switch got nailed. So I bought some Transcievers and a run of Fiber BAM problem solved. Only problem since was an antenna that got water in it and froze. Not sure it would help you but it is a possible solution fiber wont pass electricity or static charge. I now use fiber on my tower locations (wireless Internet repeaters)<br>
 
I not so sure that not grounding one end of a cable is a good idea, at least for telephone. We had a contractor installing sewers cut one of our 50 pair 24ga cables and then while still parked on top of it hit the overhead power sending 440 down the line. The end of the cable was not grounded so the electricity jumped from the back of the 66 block to the grounded frame it was mounted on. Lucky nothing was attached to it at the time, but it caused a loud noise, a bright light, a room full of smoke, and everyone to jump.

I would look into the building ground. NEC does not require the earth ground to be tested, but a good signal ground for delicate equipment should read 10 ohms or less.
 
All the grounding in the world probably isn't going to help you if your building takes a big direct hit! However, proper grounding measures will help to reduce damage when the lightning storm is local. Also worth remembering is the fact that a huge burst of released energy can be induced into other cables and circuits. I would also surmise that grounding a cable at BOTH ends would prevent any corona effect should high power be induced into that cable. The &quot;antenna effect&quot; of a cable ground at one end only, could cause large voltages to develop at the ungrounded end, which might break down the insulation and damage other equipment immediately adjacent. If in doubt, sit inside a Faraday cage!


ROGER - GØAOZ.
 
It may have not been a direct strike, I am in Ga and when something like what happaned in your case occurs, it sounds like an EMP hit. I do not think there is much you can do to stop it. The equipment will usally fail in clusters. You can protect your equipment all day on the power side and the demarc side, use proper grounding and still not stop the wrath of EMP. Unless you are in a screened room that is properly grounded.

Mike Mike
 
burying cat5 cable
I had tried to burry a cable from my house to my neighbors ... biiiig mistake ... took out 12 nics, 2 switches and 2 hubs any time lightening would strike in the neighborhood. I let it happen twice before I realized it was no accident.

SOLUTION: I went to graybar and bought some cat5-lan surge suppressors and they worked like a champ. I put one device on each side of the burried cable. My network has been welllllll tested (many storms since) and some very near strikes make them click loudly but they work like a champ. They cost around 81.00. They are 110 punch down connectors and they are polarized.

The cable should be a gel filled cat five line ... purchased by the foot from graybar. When you order it (if by 3pm) they will have it the very next morning.

I used regular cat 5 line on my network, have a yard with sandy soil and the ground does not tend to hold much water. If you have a regular yard with mud that will stay saturated with water I would recommend the gel filled line. The gel simply prevents water from reaching your lines. The gel filled line is also jacketed so you can ground it. If your using the cat5-lan suppressors its not necessary.

ITW Linx made the suppressors. They have a web site w/detailed information about the devices.

Hope this can help someone.

rats3@wolfedigital.com



may help with surges in your building ...
 
I took 5 hits in my network from 1988 to 1992 before I gave up and connected my 45 buildings via Fiber optic cables, no hits since. A nice side effect is that the faster speeds all seem to come for fiber before copper, so I have been able to move from 10 meg to gigabit with no new fiber. I tried to remain child-like, all I acheived was childish.
 
It sounds like the lightning may be entering your equipment via the 110 electrical lines. Lightning acts in strange ways when it comes in contact with electronic devices. And the NIC cards have circuits that are particularly susseptible to high voltage surges. I would install lightning protection on the AC side of the devices (Pc's, hubs, etc.)first. Especially if you have no cables attached to the network that are run outdoors.
 
This thread hit home for me. First I live in Memphis, Tenn and we get thunder storms all the time. This summer we have had more than the usual number for summertime.

A year a go my client had their 16 port switch and several NICs taken out most like after a storm. The PC's were OK except for the NIC's. They bought and I installed APC Surge Arrest Professional on each computer and the switch.

Well it happened again a couple of weeks a go. The switch died as well as several NIC's. I checked all the power strips and each computer was still plugged into each one and the green LED was on the the red LED was off. There are no other equipment going into the switch except for the computers. The cables are run through the attic (a wood frame building) sometimes running beside 120 volt romex or crossing it.

I can only guess that the lightning from the storm when had the night before I got the trouble call struck nearby and bled into the CAT 5 cable. Some of the runs are 50 feet or more.

I saw a previous post on LAN protectors and will be looking into them. Fiber is also a idea to explore. The cost is great on the front end but cheaper than buying equipment every year plus the service call and down time.

I feel better to know that I am not the only one with equipment getting zapped by lightning.
 
Well I just had my power supply blown yesterday problably due to lightning storm. We had severe electrical storms yesterday in Quebec. The electronical storms were so strong that they kept on triggering the Sensomatic alarms systems were I work. The alarms are located at the main doors to detect shoplifters. It was pretty funny, from time to time, the alarm would ring and then you see the lightning flash outside. The storm also managed to trigger the machine that de-magnatizes those alarm strips, you would hear beeps at the cash counters. Anyways, my parents had disconnected (physically from the wall) most of my computer equipment at home. Then this morning when I plugged it back in (they are on a relatively good surge suppressor from Surge Arrest, about 60$ a unit), the power supply caught fire, it was actually burning. The damage was pretty severe on the power supply, a blown capacitor (the big one about the size of a C CELL battery, it has a hole in it and is leaking), a few blown resistors and a couple of diodes. Hopefully the damage is limited to the power supply, I haven't had time to test the other components. What's odd is that the power supply blew only when I plugged it back in. So far, that's the only victim that I discovered. My other equipment which was still connected wasn't affected. I'm thinking it's the surge when I plugged the power bar back and not due to the lightning. The power supply was two years old almost to the date.

I'm off testing the other components.

Anthony
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top