Topic: Laptop rectifier overheating

[Trieste]

Google tells me that the little brick-like block in the middle of my laptop's power cord is called a rectifier, so that's what I'm calling it. Anyway, it's fine in most outlets and doesn't overhead, but in one particular outlet in my apartment, it heats up after an hour or two until it's too hot to touch. The outlet in question is properly grounded and whatnot, however we have expanded it with a 6-slot outlet brick (like this one). Usually the brick only has two or three other things plugged into it in addition to the laptop.

Is there something I can do to keep it from overheating? Is it the brick causing it? Is my power cord on its way out; should I start saving for a new one? I've only recently noticed it heating like this. During the winter months, I would occasionally rest my feet on the thing to warm up my toes, which obviously means it was warm but not too warm to touch.

Does anyone know?

[Oniya]

If it's only happening at the one outlet, it might be worth checking out how that outlet differs from others.  Have you tried plugging the laptop directly into the wall instead of into the 6-outlet brick?  You might also want to have the voltage level of that outlet checked, since rectifiers are part of the circuitry that steps the incoming voltage down to the level that the laptop can handle, and the excess gets dissipated as heat.

[Trieste]

OK, so tried it without the brick, left it in there a couple hours, it's still overheating. I'm not sure how to check the voltage, though. Is there, like, a volt-meter that I can get in Wal-mart's hardware section or sommat?

[Caeli]

I think so... something like this, I'm assuming?



You can probably get it in any reasonably large store's home improvement or tools section. If not, I'm thinking any hardware store will carry something like it for cheap.

[Trieste]

... I don't know that I want to go around sticking metal things into outlets... 

[Oniya]

Ask the guy in the wiring section.  They probably have something that looks more like a standard plug for testing outlets.

[Trieste]

I can only hope they do; electricity is scary enough as it is.

* Trieste has been known to make her lab partner handle electrodes for electrolyte experiments. >.>

Anyway, will check that out next. Thank you, Oniya! And Caeli, too!

[Scott]

They may have switched the hot and neutral inside the wall, on most things like lights, fans, and aquarium pumps it wouldn't matter or even show up, but on electronic equipment it can cause problems with things like phone chargers, comp batteries, cable boxes ect...   

A rectifier changes AC (alternating current) to DC (direct current).

Unscrew, or unplug the block. They may have left the cover plate on the receptacle, so it may have to be removed too. There are either 3 or 6 wires in the receptacle, most of the time the receptacles will be daisy chained together inside the wall, so if there are 6 then don't freak out. take the two screws out at the top and bottom of the receptacle and slowly pull it out of the box.  A black (hot 120volt), a white. (neutral), and a ground (just a bare copper wire). if it's the last in the chain (only 3 wires) you may have to check them all in that room because it may be wired incorrectly in the receptacle before it.

On the receptacle there are screws on the side where the wire is landed. One should be copper color, this is where the black wire goes, the other side should have a silver screw, this is where the white wire goes, the bare copper wire should be landed on a screw that's in the mounting bracket of the receptacle. the fin size or the grounding prong usually means you can't mess this up, but if they wired the outlets wrong you may be feeding voltage to the device from it's neutral fin which on a lot of things doesn't matter, .


how many things do you have plugged into the block, because a voltage drop (normal 120 volts, but with 5 other things running may be as low as 90 it could affect the rectifier. (you can check that with the meter if you get one, this is what I think is probably the issue with you.)

if you do buy a meter read the book, but there is a setting on it that looks simular to this "~" that's a/c, the d/c setting looks like this "- - - ". The meter, unless you spend big bucks on it, it is probably not auto ranging (the one in the picture Caeli posted isn't), so make sure it is set over 200 so you don't blow a fuse in the meter.

black wire- will shock you.
white wire- can shock you, but probably won't, if there is voltage there it probably won't be enough to even feel it.
ground- won't shock you

I wish I lived close enough to check this out for you, but I hope this helps. 

[Scott]

wait you said apartment... call your landlord and make them check it out lol.

[Trieste]

*stares at Scott's post with wide eyes* I.. I don't know if you realize that I rent...

Usually only 2 or 3 other things plugged into the block in addition to the laptop.

Edit: Riiiight... >.>

[Scott]

lol, I'm sorry honey, I was just tryin to help. 

[Trieste]

I know, I know, thank you. Just... the thought of sticking my screwdriver in among all those wires makes me shaky. I can take apart a computer and put it back together again no problem... I'll deal with the thermal gel goop all day, even. Just don't make me deal with live wires or I become a complete 'fraidy cat.

[Scott]

That's the difference, I can play with residential and industrial electricity all day long, but going inside a computer scares the bejesus out of me.

[Soran]

For now, I would just invest in an extension cord and plug it into a different set of sockets if its only overheating from that one socket. I know its inconvenient, but it's probably the cheapest option for now.

If everything else plugged into your outlet brick are fine then just leave them.

[Lord Mayerling]

Please turn the circuit off before you go playing with the outlet.

[Darius]

You can buy a very cheap multimeter at harbor freight that would be adequate for the job. First thing to do is remove the brick from the outlet and use the multimeter on its resistance setting and measure between the lug slots in each plug. You should see no resistance. Then measure from the problem lug to the lugs on the back of brick that plug into the outlet. One should be very low resistance, and the others should be open, meaning infinite resistance. Once you are certain all the lugs are wired the same, you can plug the brick back in and turn the meter over to its AC voltage setting and check the lugs for proper voltage.

For the most part, you are far better off dumping the brick and getting yourself a nice power strip with some kind of breaker protection to plug into that wall outlet. Bad electricity and laptops are a combination that often leave you looking for a new laptop! Investment in some kind of power protective device should be your top priority.