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RF interfere with External USB HArd Drive

Hi
I have a Dell server that has an External USB hard drive attached that it's used for backups.
The server is located on a manufacture that use a machine that create high Radio Frequency daily. The server is maybe 30 yards from the source of the RF but the entire building will fill the RF. Most common problems for the server is that the USB mouse and Keyboard stop working daily and the admin has to unplug and plug them back but the worst is that once and up to 3 times a week the Usb Hard Drive disappear and unplug it and plug it back multiple times to even different USB ports does not help until the server is reboot it.
So I believe that the RF are responsible since Other PC on the building has similar symptoms with the USB mouse and Keyboard.
I reboot the server last night and it was Ok all night then the problem come back around 10 AM. We are in the process of looking to see if when it happen the machine that produce the RF has been use or not. Question I have is first do you agree that this can be cause by Radio Frequencies and if yes how can we protect the server from this>
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It's definitely a possibility.
But as you are already doing, you need to verify that is the cause, before throwing resources at the wrong "problem".

Some kind of shielding around the "RF source" should be able to block most of it.
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infedonetwork

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I will test more but if it's the RF what type of Shield do you recommend for a server?
It all depends on your setup.
Are they in the same room? Different rooms? Cubicles?

How strong is the RF? Might just need to move it away from the other systems X number of feet.
It might be easier to line the wall of the room with the "RF" machine in it, with thin sheet metal, or even just aluminum foil.
You might need to "build" a cage around one or another of them.
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are you sure RF is the cause?
it may also be induction, or over the AC lines, or by poor grounding.
i would first start by checking the grounding on the server, and the machine
Well according to the end user there is other machines that has similar problems.
The problem never happen at night or during the weekend. I try too uninstall the USB hub from device manager and then search for new Hardware but the HD does not show until the server is reboot it.
Bellow is the comments of the end user.

I have replaced the USB cable and plugged into a different port (there are only four, so not much choice).

I am wondering if we are getting RF interference from our welders.  Usually when I go to the server, I have to unplug both the mouse and the keyboard because they are not responding after being zapped by the RF.  This may be happening with the backup drive as well.  If the drive stops responding overnight or on weekends (when the RF welders are off) then it cannot be the RF.  I will reset it after the machines are turned off on Friday afternoon and then if it fails over the weekend, we know it is not the RF.  If it fails on Monday morning when they start the machines then it is most definitely the RF and I do not know how to prevent that.
>>   If it fails on Monday morning when they start the machines then it is most definitely the RF  <<  not sure  - it can be cause dby a bad AC line, or spikes on it.
i still suggest to inspect the AC line and grounding first
But how a bad AC line with cause the USB ports to act like that?
I already have trouble understanding how the RF has something to do with the USB.
I will understand the RF problem if it involved wireless mouse and Keyboards or Routers or wireless cards but can't see it on a wired one.
I have another customer that has exactly what you describe about spike and bad AC line and what I see almost every month it's dead power supply and video cards but never USB devices.
If let's say that it may be a bad AC line do you think that by adding an APC with voltage Regulator on will solve the problem. I believe they have one now but it does not have voltage regulator.
how - you will only know after you found the cause, and maybe never.
discussing i does not help much at this point.
i always start by verifying the basics  = AC and ground in this case -  then build shielding systems
Strong rf field can even light TL tubes
another user has another environment, you cannot compare them like that
and a good UPS will certainly help, if it comes over AC

but tell me -  why don't you want to check the AC and grounding?? - at least you sound like that?
Must be RF. They just called again complaining that nobody can print to an wireless printer except the one user that is hard wire connect it to.
I will keep investigate it and I will post the results
i cannot tell that from here - but i want to warn you  not to jump too fast to conclusions
that's all
and : good luck finding the cause !
First thing I would do is replace the USB lead with a shielded one if it isn't built in. Can't very well do that with the keyboard or a mouse but the hard disk probably has a pluggable cable. That's not going to protect the hard disk itself but it will eliminate the 6 foot aerial that's connecting it to the computer. A Faraday cage for the hard disk may be required assuming it's just in plastic clamshell case, You can't really wrap it in tin foil or it would overheat but a biscuit tin with holes in might do the trick.

What type of welding is it they're doing and any idea what voltage it's operating at?
This is the info I got from the end user

Here is a link to the manufacturer of the machines:

http://www.cosmos-kabar.com/machinery-bar-welders.asp

We are running 3 different machines right now but they are all similar in that they produce RF interference with our phones, computers, etc.
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