Page 1 of 2
How to open a power brick?
Posted: Fri Dec 21, 2007 5:53 pm
by phool@round
This might sound silly but I have a power brick that I would like to open and reinsert the output lead. It came with a used TP I purchased and was treated rather rough. The RF shield is exposed right at the exit from the strain relief.
I don't see screws so I suppose it is glued. Has anyone every split one open and if so how? I really don't want to damage it or make it look any worse than it already is. I prefer to be kinder, gentler towards my favored equipment.
Any help is much appreciated..... FRU/PN:08K8209 72W 16V 4.5A
Posted: Fri Dec 21, 2007 7:09 pm
by Harryc
AC adapters are really cheap. Just get a new one vs. risking splitting it open, causing a short, or who knows what else ...
Posted: Fri Dec 21, 2007 7:47 pm
by spuddog
Where's the fun in buying a new one? Not to mention the cost to the environment by throwing away a good power supply. I say pry the sucker apart and give us a report on what's inside. What have you to lose?
Scott
Posted: Fri Dec 21, 2007 8:15 pm
by Harryc
spuddog wrote: What have you to lose?
Scott

Yeah go for it. Fire is good...yeah, yeah that's it. Burn baby burn..hahahahaha.
Posted: Fri Dec 21, 2007 9:07 pm
by spuddog
Seriously, if you open it up and repair the leads, then test the output how can it damage anything? I have made repairs to numerous electronics that were supposedly(non-repairable). I just hate to see someone throw away serviceable equipment.
Scott
Posted: Fri Dec 21, 2007 9:30 pm
by RealBlackStuff
If you want to risk someone's life for the sake of $15-20, by all means go ahead.
Just don't come back to us that we didn't warn you.
Of course all this equipment can be fixed one way or another, but is it worth it in the end? Hardly...
Posted: Fri Dec 21, 2007 9:51 pm
by spuddog
I didn't realize I was putting anyone's life at risk. So I will change my advice. NEVER, NEVER , NEVER, FIX ANYTHING. BUY NEW!!! THROW YOUR OLD THINKPAD AWAY!!!! (but put it up for sale here first).
Scott
Re: How to open a power brick?
Posted: Fri Dec 21, 2007 10:22 pm
by bill bolton
phool@round wrote:This might sound silly but I have a power brick that I would like to open and reinsert the output lead.
Tha would indeed be a very silly thing to do.
DONT DO IT!
There is nothing at all you can service inside the brick
including the cord termination.
Buy another power brick, they are not expensive.
Cheers,
Bill B. (IEEE)
Posted: Fri Dec 21, 2007 10:58 pm
by leoblob
To cut it open, hold an X-acto knife over the stove. Once it's hot you can cut a bit of the plastic until the blade gets too cool. Then heat it again and keep going. May sound stupid, but I've done it and it works.
I understand about wanting to open and fix stuff even if it's not worth it time- or dollar-wise. I say, "go for it"! Obviously, there are
many opportunities for personal injury using this method, but that's part of the fun.
Admin Edit: Highlighting added. ThinkPads.com does
NOT endorse this approach.
Posted: Sat Dec 22, 2007 1:19 am
by phool@round
Um......I'm glad I asked. Since I asked the question and started a heated debate I'll take the responsibility for it and moderate my own post for the sake of keeping the heat down to a low boil......
Two things I omitted from my post.
1.) Prior to posting I had contacted the seller, a new one is on the way.
2.) I intend to use the other (in question) as my test bench supply which will be unplugged when not in use. All normal behavior so far.
I like a tidy bench......
HarryC, RealBlackStuff and Bill Bolton, thanks for covering my back. I think that says alot right there. I also understand spuddog (Ah the life of an iron worker, been there.) and leoblob are ecology conscious and wild children of the sixties....... anything goes, eh? It's a transformer inside, nothing exotic to look at.
Anyways........ I'm parking the idea. Two wraps with some Scotch 88 and it's good to go. There are no electrical wires exposed, simply the RF shielding/woven stainless strain is. The inner insulator isn't compromised. The outer most cover has been stretched a quarter of an inch out from the molded cord strain that exits the case.
While it sits parked on the bench there will be no strain put to it.......
One more thing, I'm nearing the half century mark. I'm new to this forum and to repairing Thinkpads as a hobby but I am not new to danger......... I'm glad to have you guys covering my back, makes me feel warm and fuzzy ....... I'll raise a brew in your honor at the VFW.
Posted: Sat Dec 22, 2007 1:30 am
by rkawakami
<a dissenting moderator chimes in>
I've always wondered why IBM chose to have the output cord exit the power brick at an abrupt right angle. Every other laptop AC adapter that I can find in my house has the cord coming straight out. Sure, it makes winding the cord around the body of the adapter easier (and less strain on it) when the cord juts out sideways. However, when it's actually being used, the DC cord usually bends so that constant pressure is being applied to the strain relief. Is this a designed-in planned obsolescence?
If I were to design something like this I would use a polarized, plug-and-socket arrangement for the output cord. You wouldn't be able to plug it in the "wrong" way. Why a removable cord? Several reasons. You could have a choice in the length of the cord going to the laptop. Always have an adapter connected to a desk-bound dock or port replicator and don't need the normal 6' of cord? Use a shorter one. Desk too far from the AC outlet? Get a longer one. If for some reason the cord gets damaged, you could simply replace it (like in the OP's situation). It's already done for the AC cord; why not the DC side?
Properly executed, by somebody who knows what they are doing, opening up an AC adapter to re-solder the DC cable back on may be no more hazardous than years ago when people were pulling vacuum tubes out of televisions and taking them down to the local Radio Shack to test them. Unless the person doing the operation is a complete bonehead and forgets to unplug the equipment from the wall. The now-natural urge to dispose of "broken" items only makes our landfill sites grow larger and puts more strain on future generations.
I understand in today's heavily litigated society that Thinkpads.com must not appear to support this view (endorsing people to open up potentially hazardous items). That's already in the site's registration agreement ("Therefore you acknowledge that all posts made to these forums express the views and opinions of the author and not the administrators, moderators or webmaster (except for posts by these people) and hence will not be held liable."). But I for one still like to think that people who are doing something by diverting some of our high-tech trash (albeit temporarily) from the local dump or off-shoring it to third-world countries, are doing this planet a favor. Yes, it will eventually end up in the trash but for the years (?) that it continues to perform useful functions it means that it's not rotting away underground somewhere or being breathed in because it got incinerated.
<end of John Dvorak inspired diatribe... we now return control to your normally mild-mannered reporter....>
Moderator note (that's me talking): These are my personal views and does not represent the other members of this forum or the owner of thinkpads.com.
Posted: Sat Dec 22, 2007 3:03 am
by BillMorrow
the AC adapter is a very small switching power supply..
quite magical when one is from the land of linear power supplies..
i once had one i wansted to open up..
i hit it with a hammer.. lightly..
so the glue joint fractured..
played a bit and that was it..
i'm sure you're competent enough to not burn your house down..
its your call..
but the guys are right, a replacement is cheap, now..
Posted: Sat Dec 22, 2007 3:14 am
by phool@round
Thanks Bill, this has been a very polarizing topic.
I've been to both poles in one day........ I think I'll give it a West for tonight and settle on the Equator.
LOL...... a hammer eh? No one will ever know........
Posted: Sat Dec 22, 2007 10:22 am
by jdhurst
I have taken one apart to see how they tick, but it is not a reversible operation, and I would never take an adapter apart that was going to stay in service. ... JDH
Posted: Sat Dec 22, 2007 11:58 am
by phool@round
.......Thanks JD.
This topic started as a rhetorical question. It will remain in that state for the duration. I will not say that I have or have not split the case. Everyone is encouraged to continue to respond though. Maybe someone will design a modular brick one day that answers to both sides of the debate. Maybe.
Posted: Sat Dec 22, 2007 1:07 pm
by DAH
Well as someone with some age, I must confess to having been shocked more than once, and I'm still alive. Most homes I am familiar with have circuit breakers or fuses, that are designed to stop homes from burning down. Can they always be counted on to work, no...
Lately I've noticed that here on thinkpads.com some thoughts, some opinions are not wanted. I'm not suggesting that anyone go out and insert their self in an electrical circuit. But clearly many people have, and have not required a trip to the morgue. Many haven't even required a trip to the doctor. Can I guarantee that you will live if you attempt to open your power brick, no but then I can't guarantee that you'll live till tomorrow if you don't open your power brick either.
It's scary that certain voices, certain ideas, and opinions are shouted down here, now.
Posted: Sat Dec 22, 2007 1:32 pm
by JaneL
DAH wrote:Lately I've noticed that here on thinkpads.com some thoughts, some opinions are not wanted.
Well, if that was true of this thread, it would be locked or gone, now wouldn't it?
I'm not sure why cautioning someone about the possible dangers is considered shouting their opinion down. It's just... another opinion.
Posted: Sat Dec 22, 2007 2:00 pm
by phool@round
DAH, it wasn't a matter of being shouted down in this case.
"Therefore you acknowledge that all posts made to these forums express the views and opinions of the author and not the administrators, moderators or webmaster (except for posts by these people) and hence will not be held liable."
This is "THE" point that the moderators and admins are making.
It was clear the few who posted the opposing opinion didn't know or understand why they were being opposed steadfastly
at the time they posted.
I'm fine with it. I asked a question and have been given an answer. The cool part is that I got one heck of an inside answer.........lol.
This is getting way OT. Probably should hail a mod and have this moved to the "General" discussion forum.
Posted: Sat Dec 22, 2007 6:29 pm
by Paul Unger
rkawakami wrote:I've always wondered why IBM chose to have the output cord exit the power brick at an abrupt right angle. Every other laptop AC adapter that I can find in my house has the cord coming straight out. Sure, it makes winding the cord around the body of the adapter easier (and less strain on it) when the cord juts out sideways. However, when it's actually being used, the DC cord usually bends so that constant pressure is being applied to the strain relief. Is this a designed-in planned obsolescence?
You know that velcro thingy on the DC cord that always sticks to itself and generally leads to tangles and cursing? I wrap that around the body of the brick to 'secure' the DC line and hopefully prevent a 'repetitive strain injury' (and it gets the velcro out of harm's way!). I lose about 3" of length, but I figure it's worth it to extend the life of the cord (and get the velcro out of harm's way). For what it's worth . . .

Posted: Sat Dec 22, 2007 6:46 pm
by bill bolton
DAH wrote:But clearly many people have, and have not required a trip to the morgue.
While the ones that haven't aren't around to tell us about it.
I've had to personally deal on several occasions with fatalities arising from accidental electrocution due to ignoring the safety warning on mains voltage equipment. Its not nice, and the deaths were entirely avoidable.
Is your life worth risking for a potential saving of ~$20?

Posted: Sat Dec 22, 2007 6:50 pm
by rkawakami
Paul Unger wrote:You know that velcro thingy on the DC cord....<snip>
Good point and helpful tip! In my case, even though most of the Velcro® straps that are on my most often used adapters are already clogged with cat fur, they still tend to stick to the carpet, couch or itself when least desired

.
Posted: Sat Dec 22, 2007 8:00 pm
by phool@round
....... or getting hooked in the carpet, I must say that one again .......
Wrapping the Velcro strap around the the brick and around the looped DC lead is an exceptionally brilliant idea.
Posted: Sun Dec 23, 2007 12:19 am
by Ken Fox
bill bolton wrote:DAH wrote:But clearly many people have, and have not required a trip to the morgue.
While the ones that haven't aren't around to tell us about it.
I've had to personally deal on several occasions with fatalities arising from accidental electrocution due to ignoring the safety warning on mains voltage equipment. Its not nice, and the deaths were entirely avoidable.
Is your life worth risking for a potential saving of ~$20?

220v, the current where you live, is considerably more likely to kill someone than the 110v. found in the USA, Canada, and some other places. This does not excuse carelessness, and of course 110v. has its very major disadvantages, but it does have a few advantages and this is one of them.
Posted: Sun Dec 23, 2007 1:08 am
by bill bolton
Ken Fox wrote:220v, the current where you live, is considerably more likely to kill someone than the 110v.
No,
its just as likely for the people using/abusing mains powered equipment.
In general its not the voltage on the normal (moderate) voltage domestic power mains that kills people working with mains powered equipment.... its a fairly low curent flowing through the chest and impacting the heart. The AC current needed to send a heart into arhythmia is around 50 mA or so.
There are basically no significant differences for electrocution in that circumstance with ~115V or ~230V AC mains systems and they are treated as a single class globally in consideration of all deaths arising from accidental electrocution.
Bill B. (IEEE)
Posted: Sun Dec 23, 2007 10:24 am
by RealBlackStuff
Having lived in countries where they use 220-240V, I have been shocked a few times (through my own carelessness), but happily I am still around to tell so.
I experienced them as some 'tingling', similar to after you have been outside playing with snow with your bare hands, and then go inside.
Actually it's a warm, fuzzy feeling, that you can really do without.
As Ray pointed out, it's the Amperage, not the Voltage, that does most harm.
Posted: Sun Dec 23, 2007 11:21 am
by carbon_unit
It also has to do with how it travels through your body. If it goes in one finger and out another finger on the same hand you will just get a buzz. If it goes in one hand and out the other via your chest you run a chance of it affecting your heart. The same if it goes from hand to foot. 440vac is another story.
Posted: Sun Dec 23, 2007 2:58 pm
by rkawakami
RealBlackStuff wrote:Having lived in countries where they use 220-240V, I have been shocked a few times (through my own carelessness), but happily I am still around to tell so.
Same here, 'tho it's been many years. Last time that I remember it was touching the metal frame of the stove and an adjacent microwave at the same time. Seems like whoever installed the electric stove wired it in wrong (hot and neutral were reversed

<--- funny, the "shock" icon!!!).
RealBlackStuff wrote:As Ray pointed out, it's the Amperage, not the Voltage, that does most harm.
Umm, that was Bill Bolton not me.
Posted: Sun Dec 23, 2007 3:26 pm
by RealBlackStuff
My apologies to Bill. Anyway it came from the same 'family' (of mods and admins).
Posted: Sun Dec 23, 2007 5:06 pm
by phool@round
.....depends on how high the voltage is. I was given a hole through the left thumb nail by 460V 3 Phase and a very sore arm from involuntary reflex. The voltage exited my elbow through a man lift railing to ground. I was much younger. My new partner received a black left eye.......... from my right hook.
I learned two valuable lessons from that incident. Check first. Check twice.
Posted: Sat Dec 29, 2007 6:06 pm
by frankiepankie
rkawakami wrote:<a dissenting moderator chimes in>
If I were to design something like this I would use a polarized, plug-and-socket arrangement for the output cord. You wouldn't be able to plug it in the "wrong" way. Why a removable cord? Several reasons. You could have a choice in the length of the cord going to the laptop. Always have an adapter connected to a desk-bound dock or port replicator and don't need the normal 6' of cord? Use a shorter one. Desk too far from the AC outlet? Get a longer one. If for some reason the cord gets damaged, you could simply replace it (like in the OP's situation). It's already done for the AC cord; why not the DC side?
I think that is because safety reasons. If you connect the AC cord, so the brick is powered, DC is coming out from the other side.
But, lets think you have some metal pieces lying around, and accidentally, the metal pieces are touching the DC output connector......
That is bad stuff!!!