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  • Posts: 84
  • Registered: ‎12-09-2009
  • Location: United States of America
  • Views: 1911
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How to not destroy a W520 power supply during voltage drops

2014-12-11, 15:28 PM

Hi all,


I'm currently living in a poor country where when we have electricity at home, the amount power is sometimes barely enough to charge cellphone. (It used to be better, but it seems the freezing weather has caused some infrastructure problems). Recently I was using my W520 before I realized the power had dropped, and the power supply stopped working for some time. Fortunately it came back to life!


I need to educate myself about the dangers of operating in such conditions. I have purchased a multi-meter to help me determine when it's unsafe to plug-in the power supply. I'll read up about how to use this gadget (including the basics of how electricity works) but meanwhile I'd be delighted if someone can shed some light on the following:

  1. When the voltage drops below 100 volts is that the time to immediately unplug?
  2. If the laptop is off and the battery is being charged, is it less critical to uplug it?
  3. Am I going to destroy this power supply by using it in conditions where the voltage can unexpectedly and suddenly drop?
  4. Is buying  an automatic voltage regulator (AVR) a good or bad idea? I saw in the shops that they too have a minimum voltage, which in this (in theory) 240V county is about 140V. Below 140V and I guess the AVR won't work at all. So it looks like it will do nothing to help serious voltage drops, but will it help preserve the life of the power supply otherwise? Disconcertingly, I read here on wiki travel that "Voltage stabilisers can introduce surges if there is a power outage. The cheaper and most common relay type can also damage electronic equipment."

Thanks in advance.


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