3 ms·

Everytime i turn on my fan, my computer screen goes black for 2 seconds, only when used on same outlet.

encom 6y ago
Back in Windows 98 times, I had bought a new halogen desk lamp. I put it on my desk, turned it on, and my machine promptly BSODed. It was reproducible as well. The switch on that lamp was effectively a "push here for BSOD" device. What probably happened was high inrush current on the iron core transformer, and shitty 90s chinese power supply caused the opposite of a voltage spike, which I don't know the english term for. The lamp became my bedside table lamp. A duty it serves to this day.
- nfriedly 6y ago
  > opposite of a voltage spike "Voltage drop" or "brownout"
LeonM 6y ago
That's not RF interference, but a phenomenon known as brownout [0]. When the fan spins up it draws more power, this causes the voltage to drop at the outlet, which causes the powersupply in the monitor to (temporarily) shut down. Normally, this shouldn't happen. So either the monitor is badly designed or old (the capacitors may have dried out), or you have a wiring issue in your house. The latter is a fire hazard. You should test the same scenario with other outlets in your house. If it does not happen there, then there may be something wrong with the wiring to your computer outlet, have an electrician look at it. [0] https://en.wikipedia.org/wiki/Brownout_(electricity) https://en.wikipedia.org/wiki/Brownout_(electricity)
- encom 6y ago
  Electrician here. Measure voltage at the outlet. It should be +/- 10% of nominal voltage. Eg. 207-253 in 230 volt land. You have to measure under load, so plug in some high current device. If voltage drops below 207 while a resistive heater is running, call somebody.
- popotamonga 6y ago
  Weird its a newish monitor 1 yr, also the pc is connected there and no issue. The one not usual thing is that they are all connected to a tplink powerline. ill try without the powerline.
  - mturmon 6y ago
    Note to armchair troubleshooters nearby: It seems to be a passthrough connection from one of these: https://www.tp-link.com/us/home-networking/powerline/tl-pa7010p-kit/ https://www.tp-link.com/us/home-networking/powerline/tl-pa70... There are two types of fan motors, AC and DC. A lot of small fans would be DC fans, which have their own power supply/converter. Larger ceiling fans are often AC fans. Depending on where you are in the world, one or the other type might be common for some applications. In my experience, a small desktop fan would be a DC fan. Both fan types have transient behavior at startup. It takes more energy to get the fan moving than to keep it moving. In principle, a basic fan looks something like a short circuit when the blades aren't turning. This startup behavior manifests differently for AC vs DC fans. For more, here's a good summary showing steady-state current draw (figs. 3/4) and startup (fig. 5). https://www.digikey.com/Web%20Export/Supplier%20Content/ComairRotron_25/PDF/Comair_Tutorial_BrushlessDCFans.pdf https://www.digikey.com/Web%20Export/Supplier%20Content/Coma... Maybe the passthru connection on the TP-link doesn't like the inrush current demand -- and it's not the outlet itself.
    - popotamonga 6y ago
      Thats the one. Took it out no more blackouts.

Back in Windows 98 times, I had bought a new halogen desk lamp. I put it on my desk, turned it on, and my machine promptly BSODed. It was reproducible as well. The switch on that lamp was effectively a "push here for BSOD" device. What probably happened was high inrush current on the iron core transformer, and shitty 90s chinese power supply caused the opposite of a voltage spike, which I don't know the english term for. The lamp became my bedside table lamp. A duty it serves to this day.

nfriedly 6y ago
> opposite of a voltage spike "Voltage drop" or "brownout"

LeonM 6y ago

That's not RF interference, but a phenomenon known as brownout [0]. When the fan spins up it draws more power, this causes the voltage to drop at the outlet, which causes the powersupply in the monitor to (temporarily) shut down. Normally, this shouldn't happen. So either the monitor is badly designed or old (the capacitors may have dried out), or you have a wiring issue in your house. The latter is a fire hazard. You should test the same scenario with other outlets in your house. If it does not happen there, then there may be something wrong with the wiring to your computer outlet, have an electrician look at it. [0] https://en.wikipedia.org/wiki/Brownout_(electricity) https://en.wikipedia.org/wiki/Brownout_(electricity)

encom 6y ago
Electrician here. Measure voltage at the outlet. It should be +/- 10% of nominal voltage. Eg. 207-253 in 230 volt land. You have to measure under load, so plug in some high current device. If voltage drops below 207 while a resistive heater is running, call somebody.
popotamonga 6y ago
Weird its a newish monitor 1 yr, also the pc is connected there and no issue. The one not usual thing is that they are all connected to a tplink powerline. ill try without the powerline.
- mturmon 6y ago
  Note to armchair troubleshooters nearby: It seems to be a passthrough connection from one of these: https://www.tp-link.com/us/home-networking/powerline/tl-pa7010p-kit/ https://www.tp-link.com/us/home-networking/powerline/tl-pa70... There are two types of fan motors, AC and DC. A lot of small fans would be DC fans, which have their own power supply/converter. Larger ceiling fans are often AC fans. Depending on where you are in the world, one or the other type might be common for some applications. In my experience, a small desktop fan would be a DC fan. Both fan types have transient behavior at startup. It takes more energy to get the fan moving than to keep it moving. In principle, a basic fan looks something like a short circuit when the blades aren't turning. This startup behavior manifests differently for AC vs DC fans. For more, here's a good summary showing steady-state current draw (figs. 3/4) and startup (fig. 5). https://www.digikey.com/Web%20Export/Supplier%20Content/ComairRotron_25/PDF/Comair_Tutorial_BrushlessDCFans.pdf https://www.digikey.com/Web%20Export/Supplier%20Content/Coma... Maybe the passthru connection on the TP-link doesn't like the inrush current demand -- and it's not the outlet itself.
  - popotamonga 6y ago
    Thats the one. Took it out no more blackouts.