I have a question about a computer I'm using.

The AC adapter is making a strange noise and it is causing downstream GFCI outlet in my bathroom to keep ' clicking ' loudliy and triping.
It is an iGo universal on a toshiba notebook. Has a 2 wire ( no ground ) AC cord, the adapter is also sort of fizzling and whiring softly. it does not get overly warm or perform oddly to me; however it is causing the outlet the keep poping. this seems to happen when the computer/CPU is under a load because i can hear the outlet in the back rooom click as i open programs and move about the OS.

does anyone know what can cause this? is it dangerous?

* also the sound that it's making is very strange. It is like a sizzling/ poping with an occasional capacitor like whirr. sounds very bad but perhaps normal?

 

The adapter is broken and if it is tripping a breaker then I would have to say it is a risk.

It is a switch mode supply and when things go wrong then they can make such sounds. It may continue doing this for some time but I expect it will eventually stop working completely, possibly with an audible pop, crackle, or just plain bang.

 

does anyone know what can cause this? is it dangerous?

I can tell you how a GFCI works. The GFCI looks at the current in both legs, Line and Neutral or Hot and Neutral. The current should be the same. Simply put current in should equal current out. The difference between current in and current out should be zero. Anytime there is an imbalance exceeding about 6 mA (0.006 Amp) the GFCI should instantly trip. On a two wire device like you have I am not sure why it trips a GFCI. With some motor circuits there can be "leakage" which will cause a GFCI to trip but in the case you describe I don't know where there could be any leakage. Therefore I really can't say why you are getting "trips" but obviously it is not normal, there is a small current leakage somewhere. I also can not say if it is dangerous or not. I can in simple terms explain what causes a trip. GFCI outlets also have a Line and Load side so a few standard outlets can be added down the line and be protected. You may want to have your GFCI checked by a competent electrician as something doesn't seem right.

<EDIT> I see Albert answered while I was slowly typing.... </EDIT>

Ron

 

I can tell you how a GFCI works. The GFCI looks at the current in both legs, Line and Neutral or Hot and Neutral. The current should be the same. Simply put current in should equal current out. The difference between current in and current out should be zero. Anytime there is an imbalance exceeding about 6 mA (0.006 Amp) the GFCI should instantly trip. On a two wire device like you have I am not sure why it trips a GFCI. With some motor circuits there can be "leakage" which will cause a GFCI to trip but in the case you describe I don't know where there could be any leakage. Therefore I really can't say why you are getting "trips" but obviously it is not normal, there is a small current leakage somewhere. I also can not say if it is dangerous or not. I can in simple terms explain what causes a trip. GFCI outlets also have a Line and Load side so a few standard outlets can be added down the line and be protected. You may want to have your GFCI checked by a competent electrician as something doesn't seem right.

<EDIT> I see Albert answered while I was slowly typing.... </EDIT>

Ron

thanks for reply.

it is strange to me because I have the laptop plugged up in the kitchen; but what you said makes sense. I'm in a 1998 Fleetwood single-wide, and in the kitchen, the outlets all have a ShockFinder sticker, though they are not GFI. perhaps there is leaking current on the neutral line of my laptop? bad transformer?

 

The kitchen outlets are likely on the load side of the bathroom GFCI. Here in the US GFCI is mandatory in Kitchen and bathroom. While I am not sure how much a mobile home would differ I would guess it needs to comply with NEC. That would also explain the sticker you see on standard outlets. Again knowing how the GFCI works if it is tripping the GFCI is either defective or there is some leakage somewhere. Only a very small imbalance is needed to trip a good working GFCI. Leakage can be inductive or capacitive in nature but the end result is current in does not equal current out. Transformers can have leakage but what gets interesting is with a two wire system where would any leakage go? Then too, possibly the GFCI is beginning to fail. Really hard to say why?

Ron

 

On a two-wire adapter, if you measure the AC voltage between one of the output pins and earth you will generally measure close to half the AC input voltage. There is clearly leakage, probably mostly capacitive, and whatever current flows through that leakage path implies current in not equal to current out. The design of the adapter should limit that current to a safe value and below GFCI trip levels, however age and voltage transients may increase that leakage current, possibly giving rise to the symptoms described. The noises made by the adapter surely indicate that something is wrong with it and the GFCI tripping may be coincidental but the odds are against it.

 

If the adapter is making strange noises, I would regard it as unsafe for continued use. There is a fire risk.