Macbook charger teardown: surprising complexity inside Apple's power adapter • Hacker News Board

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#211

Post by dereg » Wed, Nov 25, 2015, 11:15 PM UTC

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

While it does suck that all of Apple's chargers fray so easily, however I don't see it as a reason to be cynical about their products. In this case, Apple seems to be prioritizing environmental friendliness over function here. The cables are so weak because they have specifically removed PVC from their charging cables.

http://www.apple.com/macbook-pro/environment/

> The greatest environmental challenge facing the computer industry today is the presence of arsenic, brominated flame retardants (BFRs), mercury, phthalates, and polyvinyl chloride (PVC) in products. Apple engineers have worked hard to eliminate BFRs and PVC from MacBook Pro circuit boards, internal and external cables, connectors, insulators, adhesives, and more.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#212

Post by ddingus » Wed, Nov 25, 2015, 11:16 PM UTC

Bud wrote: post #169

Alupis wrote: post #161

Earlier quoted context omitted.

Way back in my computer repair days, I used to commonly see macbooks with horrendously frayed and/or just generally poor condition chargers. While, other laptops didn't seem to have that issue nearly as often (although breaking the DC jack was a common problem for those folks, but that's a different issue). You shouldn't have to be tender and gentle with the power cable for your device... it should be durable and sta…

Great, so you explain how Apple's design is faulty, and how it could be improved. I think you'll find this is easier blustered about than done. PC chargers, for instance, are universally worse. A lot worse. This design already does the best job in the industry at handling hard yanks——that's what MagSafe is for. And it does fine with ordinary, expected use and abuse of the cable. And it does great with being thrown in…

>>This design already does the best job in the industry at handling hard yanks——that's what MagSafe is for.

Absolutely not.

I use a MacBook Pro, with the MagSafe feature hard, right along with a Lenovo higher end laptop. They both travel, they both get the same treatment.

I have gone through several Apple chargers. I have had exactly ONE Lenovo charger. The same was true for my older T60P and it's charger. In fact, that one is still like new, despite 10 years of use.

I like the MagSafe, and it has prevented a few strong yanks, or trips over the cord from damaging the Mac, but it's also prone to failure in the wire near the MagSafe connector, just as it's prone to failure in the wire near the charger assembly.

Interestingly, the Lenovo chargers ship with a nice Velcro wire retainer that is intended to be used right after WRAPPING THE WIRE FIRMLY around the charger. And the Lenovo devices have both easily gone a couple thousand use cycles, the older one maybe a couple more.

There really isn't a single metric, other than size, that favors the Apple charger in my use case.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#213

Post by gutnor » Wed, Nov 25, 2015, 11:32 PM UTC

Alupis wrote: post #167

weland wrote: post #18

This is a pretty interesting article! I raised more than my fair share of eyebrows by telling people I'm not really surprised with this kind of complexity (note: I'm an EE by formation, I took a frickin' two-semester course on power supplies) but that it doesn't fully justify the price difference. Also, Jobs was a blatant liar :-). The SMPS in any modern computer is based on a standard topology that Rod Holt -- thoug…

It's interesting that most of the author's claims about quality (and reasoning to not buy a non-Apple brand power supply) boils down to "look at all the extra stuff on the circuit board in the apple power supply". Surely not everything Apple put in the charger was absolutely required, and that also doesn't mean someone else couldn't deliver the same quality with less components.

The main take away message though is the proper isolation you get in the Apple one.

And that's the actual conclusion of the author. Don't buy the other one, not because the extra stuff in the Apple one is worth it but because the others generally cut a corner too far. ( or worded differently, if you don't have the skills to assess the safety of the design from the cheap one, buy the Apple one )

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#214

Post by radoslawc » Wed, Nov 25, 2015, 11:40 PM UTC

radlad wrote: post #154

jegutman wrote: post #113

Earlier quoted context omitted.

I have a cat. None of my other charging cables are vulnerable except my macbook pro one. I've already lost two! Even if they made it easier to replace just the cable that goes from the adapter to the macbook it would be a big win for me.

My cat destroyed mine just last night. :( He has, admittedly, destroyed some headphone cables already, but $15 + some soldering is nothing compared to $80 for my Macbook charger.

Just a vent and kind of warning: I've got cat for 1.5 year, and this confirms my impression that they are horrible animals to be pets. Clawing everything, chewing on expansive stuff, peeing, vomiting, defecating on bed, sofa, chairs. If you're considering having cat, please think twice.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#215

Post by Alupis » Wed, Nov 25, 2015, 11:41 PM UTC

Bud wrote: post #210

Alupis wrote: post #180

Earlier quoted context omitted.

> PC chargers, for instance, are universally worse. A lot worse. This is an unsubstantiated claim not backed by any evidence. In fact, your original post speaks against your very claim - you advocate people be ginger with their chargers or risk breaking them. > This design already does the best job in the industry at handling hard yanks——that's what MagSafe is for You mean to say "that's what MagSafe was for". Magsaf…

Alupis: I should have clarified that I was speaking from my own personal experience with supporting hundreds of laptops. You're right. I admit that my evidence is anecdotal, but there is a lot of it. As others have already pointed out, no, MagSafe is not gone. Dell's chargers, as do many other PC chargers over the last 10 years, routinely break the charging port on the computer if they get yanked on too much, which i…

> from my own personal experience with supporting hundreds of laptops

I'm curious to how much hardware support goes into this, since most Apple machines are designed to not be support friendly (eg. non-replaceable and/or difficult to replace normal wear-n-tear components).

> routinely break the charging port on the computer if they get yanked on too much

Yes, most laptops have this issue, although it's not nearly as common with modern laptops as it used to be. However, I contest that's a design fault in the laptop, not the charger.

> which is of course far more expensive to replace than a new charger

Not always true.[1][2] DC jacks can often be bought for less than $5 online, and then it's just labor to solder it into place. A search online turns out quite a few services for $75 inclusive of the DC jack cost (your local repair shop probably does it even cheaper now, since no shipping involved, etc). Apple's cheapest adapter with magsafe cable on it is $79. A Thinkpad charger will only run you $59.99.[3]

> You're bitching a lot about my evidence being anecdotal because it's only based on hundreds of chargers, and you're right, but your evidence appears to be based on, um, a single Dell charger that you think is awesome. That seems pretty weak.

It's difficult to comment on this without resorting to some sort of "fanboy" argument.

> I think it's stupid and a step backwards and I wish they had retained MagSafe on that model.

I think we both agree on this. Worse off, if that single port breaks, you now cannot charge your laptop, nor use any peripherals (and a peripheral is more likely to break that USB port than the charger in my experience - such as a USB thumb drive hanging out and someone smacks it on accident). Even worse off, that port isn't easily repairable, so it's back to apple (who will replace the entire motherboard as their "fix", or if it's out of warranty, it's time to buy a new laptop).

[1] http://www.apple.com/shop/product/MC461LL/A/apple-60w-magsaf...

[2] http://repairmydcjack.com/

[3] http://shop.lenovo.com/SEUILibrary/controller/e/web/LenovoPo...

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#216

Post by ghaff » Wed, Nov 25, 2015, 11:43 PM UTC

cptskippy wrote: post #207

Bud wrote: post #122

Earlier quoted context omitted.

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

> Apple HAS implemented strain relief Apple favors form over function and tries to make their cables in interfaces as small as possible. The result is that there's no room left in their designs for adequate strain relief. They end up using the smallest cables they can get away with and have a bushing around the cable as it enters it's housing to protect against lateral force and that's about it. There's rarely any in…

The odd thing is that the cable going to the laptop is probably too thin/not stress-relived enough (I've "only" had one fail but it seems a marginal design). However, at the same time, the alternate plug with the extension length of cord attached practically looks and weighs like something I'd attach to a mainframe. I don't travel with it for that reason. It's always seemed to me as if the two different components were designed by engineers who didn't even talk to each other--and it's been that way for years.

There may be a UL thing going on at the 120/240V side of the charger but it still seems ridiculously overengineered.

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#217

Post by Kluny » Wed, Nov 25, 2015, 11:43 PM UTC

mschuster91 wrote: post #86

What I wonder: EVERYTHING is available as China knockoffs, but I have yet to see a fake, replacement MagSafe connector...

I have. I bought a replacement magsafe from one of those little outfits that buys "old macbooks in any condition! ca$$h today!" and refurbishes them. I paid almost full price for it thinking it was OEM, but when I got home and matched it up to my extension cable, it was obviously a cheap knockoff. Worked well enough even though it was unsightly and difficult to use (the extension cable was really hard to slide on and off), but at $85 compared to OEM at $90, why bother?

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#218

Post by radoslawc » Wed, Nov 25, 2015, 11:45 PM UTC

throwaway420 wrote: post #30

Despite the visual appeal of their products, Apple normally does a very good job with prioritizing function over form except in this case with the charger wire being so fragile and thin. I know I'm not the most careful and delicate person in the world, but the failure rate here is ridiculous compared to other similar products I own. The end of the cable gets frayed every single time. Otherwise, Apple makes ridiculous…

That looks to me as smart way to earn some aftersale money. Notice that it's not MacBook that's breaking so it's not sending wrong message that they break often. Charger is still nothing compared to price of whole set. Third party chargers I'd assume are detected by ton of electronics inside MagSafe plug and motherboard and charge slower or not at all. Bonus points: for cable breaking you can always shift blame to customer "bad handling".

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#219

Post by hobs » Wed, Nov 25, 2015, 11:50 PM UTC

PhasmaFelis wrote: post #184

Bud wrote: post #122

Earlier quoted context omitted.

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

If using a product in the most obvious and intuitive way causes it to fail, it's the product's fault, not the user's. It should be redesigned so the obvious use is the correct one. Plenty of laptop power supplies have cables designed to wrap around the brick for storage and don't have failure rates like this. Apple has not implemented proper strain relief, with a perforated sleeve (presumably for aesthetic reasons),…

And that is why they have an internal kbase article talking about that cable fraying, and have safety kbases on that as well, or did 5 years ago when I worked there.

- Former apple support guy

Re: Macbook charger teardown: surprising complexity inside Apple's power adapter

#220

Post by lostgame » Wed, Nov 25, 2015, 11:50 PM UTC

samstave wrote: post #183

Bud wrote: post #122

Earlier quoted context omitted.

I support around 300 Macs for work. In my extensive experience, the deal here is that people are FAR too rough and careless in winding up those charger cables over and over. Apple HAS implemented strain relief here and done their best to make the points of failure less vulnerable. Here's a tip: Instead of yanking the cable at a 90-degree angle and winding as tightly as possible, let the cable come out of the charger…

I am a charger hoarder: One at work, one in the backpack, several at home. Take my phone for example - I tend to have a charger in every room of the house, several for my backpack and one at my desk.

This wouldn't be an issue if Apple's chargers weren't so proprietary to the point where third-party developers can't even manufacture their own devices.

I wonder if they'll allow non-Apple USB-C chargers. I think they'd have to.