room lights blink when laptop is on charging with ups

[isohail]

Hi,

I've got a serious problem which I've been noticing since i bought a used lenovo t400 a couple days ago.. Overall it is in perfect condition, no problems.. But don't know why when the power is out and UPS is on (which powers the full house) I see the lights start blinking continuously, (not too much, but when look at the wall or bulb, i feel it alot and when i unplug my charger pin from laptop then it stops blinking and goes back to normal.

Just worried, WHY SO? a possible problem with charger or motherboard? it has 90w charger, i've used 90w charger with other laptops too.. i had t61 before with the the same charger of 90w. but this has another genuine charger of its own..

Kindly help..

 

[EasyLover]

I don't prefer charging electronic devices on UPS. Anyhow, what Watt UPS you are using and how many lights/devices are on UPS backup?

 

[isohail]

Thanks for paying attention EasyLover, I try not to charge on ups too, but somtimes i've to when needed. I guess the specs of my ups are: 1000VA/660 Watts / 12 V DC /230VAC (Isolate). There is not much load on it right now, only 4 energy savers and an LED tv, even if everything is off, it still does so. i just checked.

 

[EasyLover]

Either the batteries of the UPS are not fully charged or some loose wiring may be causing the problem with this charging.

 

[isohail]

Good guess, but i dont find any such problems. Suppose it is so, then why it happened on this laptop only, not happens on another dell. i just dont have another charger to identify so i believe something is wrong, either in charger or laptop. what's your guess if we look at it this way?

 

[EasyLover]

Yes, i overlooked that way. Sorry for that. If that is the case then my first suspect would be bad charger.

 

[isohail]

yea mine too, will check it by buying some 65w charger tomorrow, do you think it would create some problem downgrading 90w to 65w?

 

[EasyLover]

Should not. Plz confirm from the shop as well from which you would be buying.

 

[isohail]

OKay.. thanks for the time! much appreciated!

 

[EasyLover]

Even this could simply be bad charger at 90W. You may try new 90W charger but then it is a risk if you are willing to take.

 

[isohail]

yea, its a risk i know.. this charger seams genuine you know. Am just confused, it is charging good and working fine. Now its a problem i can't check at the shop. They will just say it is charging and thats it.

 

[EasyLover]

If you can grab any 65/90w charger without buying it just for checking purpose you can check the charger issue easily. It can be taken from relatives/colleagues etc

 

[EasyLover]

I once charged my mobile on UPS and my phone's charger was damaged.

 

[isohail]

I'll try to find someone who has lenovo, in my circle, a few have HPs and Dells only,, and at the shop, there would hardly be the UPS to check the fluctuations of setup or lights in the shop. Kinda tricky part but makes me curious to solve it.. I'mma do it.