Hi everyone,
My wife bought some night lights for the home and we have them in the kids rooms too (those cheap dollar store $1.25 types that comes with a bulb too). After a few months, one started to act funny. The switch wouldn't turn it off! I was concerned it may be a safety issue, and I didn't want to unplug it all the time either. So I decided to make a video teardown and see if I could fix it.
To my surprise, the construction was very simple and I figured out why it wasn't turning off. The switch worked by pressing a metal tab against one of the plug contacts. After a few months, the metal tab stopped being "springy" and therefore wouldn't spring the contact open when the switch was in the off position. You'll see that in the video below (jump to 11:25 if you want the short version).
It only uses a 4 W bulb, so the current running through is small.... according to my calculations, 33 mA based on a 120 VAC outlet. So looking back I don't think there is any safety issue with that tiny amount of current. The fact that the 4 W bulb is there definitely protects the circuit from having enough current to arc across, so I wouldn't expect any spark or arc-weld or burning to happen. Still, I am not too impressed with the construction of the switch and I was wondering if that was considered normal, something UL would approve, and/or if this compares to other night lights? Or do you think it is sub-standard? Please let me know your thoughts. I was just surprised... maybe I shouldn't have been.
A few things about the video... I can't add annotations anymore (YouTube stopped it) so corrections... US CA is USA and Canada I presume, not California as I said in the video.
Also near the conclusion of the video I also say some stupid things about spark-gap and short, which doesn't really make much sense in this context.
Again, considering it is using only 33 mA, I don't see any real safety issue from electrical point of view... I am curious as to whether this is "normal" and what to expect from such a device as I haven't opened any others up so I have nothing to compare to. Also if you want to just jump to the conclusion go to time 11:25 in the video.