USB Hub Cuts Out from Light Switch

March 29, 2019 at 07:16:29
Specs: Windows 10
I have my laptop plugged into a power strip that is plugged into a wall outlet.... well, duh.... anyway......
Laptop has a USB hub connected to it. The hub gets power from the USB connection. To the hub are two external drives. They are in turn plugged into another power strip in the same outlet as the strip the laptop is on.
Also a mouse is in the hub.
I have a light and ceiling fan on the switch in the room. Okay. Turning on is not a problem. But when I turn off the fan/light, my laptop makes noise that the external drives got disconnected (which affects data so this bothers me). At first I thought turning off the fan sends some sort of spike and the power of the external drives cut out (because nothing else has a power issues) but the mouse also does not work. The USB hub has a light, and the light stays on when plugged into the laptop, but when turning off the room fan, the mouse and externals will lose access to the hub for a few seconds.
Any idea how this would happen if the hub is only plugged into the laptop for its power, but its connected devices drop when a light switch in the room is turns off?
Thanks.

I reply as fast as I can, but it could be hours or months.


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#1
March 29, 2019 at 07:33:31
Any time you turn on/off an incandescent lamp (or other electrical device), a surge current is usually sent/removed to turn it on/off for a brief millisecond or so. Your P/S in the laptop may be sensitive (either because it's failing or heavily loaded) to this, causing the attached USB Hub to suddenly lose some power (especially if you have the hub loaded down with more than one device). If you remove the hub and turn on/off the light/fan, does the mouse still work? Does it happen on any other circuit in your home?

"Channeling the spirit of jboy..."

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#2
March 29, 2019 at 08:51:57
I suggest you get a powered USB hub. Unpowered USB hubs are designed for lower power devices like flash drives. I assume the USB hard drives are of the mechanical type?

Modern computers have more than one USB port per USB controller and have a finite current rating. This means an adjacent port may be running of the same USB controller and the USB hub, which will further load the controller.

Using an UPS in front of the power switch should smooth out peaks in the voltage.

One last point to make is that IF your wall outlet is controlled by a wall switch there is a good chance that 1 plug on the duplex outlet MAY be hot all the time and 1 May be switched. Better to NOT supply current to your computer through a wall switch if you can avoid it.

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#3
March 29, 2019 at 16:08:18
There is also the possibility that it is radio interference (spike) rather than injected via the domestic power supply. Arcs are drawn when power is broken. Whichever way the spike is injected, if the fan is worked from a normal room switch then try a different switch. The hope is that a replacement will have a snappier or cleaner break. Another idea is to fit a 0.01 MF capacitor across the light switch but be sure that it is rated at 500 peak AC (minimum) and that it is NOT polarised (electrolytic).

Always pop back and let us know the outcome - thanks


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#4
March 29, 2019 at 21:41:23
I would do two things up front because they should be anyway and probably would solve this also.
The first would be to use a UPS (also termed battery back up) out of the outlet and run your electronics all off that for its protection (as recommended above). It will absorb voltage spikes and fill in voltage drop outs which will eliminate all kinds of electronic glitches and extend the useful like of the hardware much better than a power strip/surge protector. The second is to use a powered USB hub (also as mentioned above) because you are running at a fixed location and are running hard drives through it on a regular basis.
If these do not completely resolve the issue then the further investigations may be necessary but these I feel are essential to your set up.

You have to be a little bit crazy to keep you from going insane.


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#5
April 13, 2019 at 06:06:41
I am going to have to move my power cords around or something. This is what I got.

Turning off the bedroom switch, where all my tech is, is not the only problem. The kitchen switch is now doing it, and that is 25 feet away.

I unplugged power from the laptop but it still happens. So this surge is not going through laptop power.

The USB hub is connected to the laptop directly. Self powered. There are three devices to it. A wired mouse and two external drives which have to be plugged into power.

I am guessing somehow something is happening when I turn off certain switched in the apartment now, they affect the external drives which spikes the USB hub, causing even the mouse to not work? My basics of electrical currents and computer equipment may be out of date. I am not sure if this is what si exactly happening. Those externals are the only things plugged into the wall (when the laptop is unplugged) when that USB hub cuts out... :/

Coming out of the bedroom wall outlet is...
> A seven outlet extender with some things plugged into it like, still, the plugs for my monitors from my dead desktop
> The other output has a 7-plug surge protector where all the drives are connected to.
>> Also to that is another 7 outlet extender where items printer, network router, home phone, laptop power are connected.
>>> And because of some of these plugs are big blocks, I have another extender just so the rest can fit like an Ethernet hub, external speakers, and open slots for charging an external mobile device or the vacuum (because the main outlet is occupied).

I need to rework where things are plugged in I guess into this wall outlet. Unfortunately, the next closest wall outlet is too far for any of this gear to plug into because in another corner of the bedroom and other cables will not reach to the computer.

At least I ruled out surges through the laptop power cord, and now confirmed when using the light to see the coffee maker, I am not affecting the drives in the bedroom.

Fun times.

I should go back to using candles for light like we did long ago. Those were fun times! But the smoke detector they have installed is so very SENSITIVE!!!

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#6
April 13, 2019 at 09:40:15
Do not underestimate this being "radiated" energy as I said earlier - it is something I've experienced with various pieces of equipment over the years. Sparks cause RF transmission and cables can act as an antenna. You might find re-arranging cable locations and keeping them short has a bearing on this. You could have some faulty cables or badly designed plug-in hubs around too.

EDIT:
One other long shot related to the above. Are you using external speakers? If so I've found they can pick up interference and inject it into devices. If the problem goes away when the externals unplugged then you are on to it and there are possible remedies.

Always pop back and let us know the outcome - thanks

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#7
April 13, 2019 at 12:00:35
The reason I have not gone through with this extensive troubleshooting and patience is, well, reasons of how much space I have to deal with and the amount of time doing it. Been at this now for six hours today. Moving things and testing bit by bit a dozen times, changing ad moving cables, and doing that step a dozen times.
Yes, I agree it has to now be some electronic interference. I redid all the power cables. I had everything unplugged from power, including external speakers, router, phone, drives, etc. Nothing is in the wall socket. Only thing powered on was laptop (unplugged, running on battery). Plugged in the USB hub into the laptop and one device into the HUB. Flipped the light switch in the bedroom a bunch of times and it still happened. The laptop lost USB connection.
Either some electromagnetic waves are affecting the USB hub itself, or the laptop.
At least I know it is not an AC power cable issue with any of the electronics.
So with this prepared of things moved, I switch USB hubs with one I use for job work. So far for a hal hour of switch flip testing, my laptop not lose USB connections. I turned power on to speakers, phone, modem. No change. So maybe it is my personal HUB? So I put that into my work laptop with a cell phone, keyboard, and mouse (because I hate using laptops period I need full size devices). Did more flip testing for another half hour expecting my personal HUB to fail on the work laptop, or my personal laptop to fail using the work hub. Nothing. Nothing lost connection. Everything is still on the desk, the same spots.
Been an hour now and nothing has failed (yet). So maybe it could be my personal laptop does not like working with my personal hub anymore?
I will keep my eye on it.

<just watch, as soon as I click POST and turn off the light, something will disconnect>

I reply as fast as I can, but it could be hours or months.


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#8
April 13, 2019 at 21:23:01
It could be a weakness in the hub and the other machine is more tolerant of it. A new hub may be advisable.
If it resumes happening I would consider changing out the wall switches that appear to be possible causes with new ones and possibly even the wall outlets with new ones.
Also as said, avoid long power cords and USB cords and keep all non-power cords away from the power cords (running them along side each other is much worse than one crossing over the other as it can introduce a current into the signal wire by induction).

You have to be a little bit crazy to keep you from going insane.


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#9
April 14, 2019 at 04:32:11
I just popped back to virtually add the first sentence in #8 but was obviously pipped to the post. It could be a screening issue.

Trying things one at a time might give some clues too. Wrap long leads to and fro (about 5 inch bundles) and just pop tape around them. This can help cancel out interference pick-up.

Always pop back and let us know the outcome - thanks


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#10
June 5, 2019 at 05:37:44
So far my last statement still stands. No issues. Switched hubs and no issues. So the hub I connect to my personal laptop with those same drives has had no issues. And the hub that did have issues works fine on my work laptop.
So hub 1 does not like being on laptop 1, but works fine on laptop 2.
Meh....
Thanks, all.

I reply as fast as I can, but it could be hours or months.


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#11
June 5, 2019 at 10:29:41
Good to hear - thanks for feedback.

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