Have you designed early life failure into a product?

[aargee]

Or in other words,  knowingly or been forced to fit a design to a life cycle much smaller than customers/end users would expect?

I can understand that the race to the bottom in quality causes corners to be cut, etc. but designs that are planned to fail close to the end of warranty (or other milestones in a product's life)

I have never been in the design cycle for new products, I'm a field service engineer, fixing stuff or inventing kludges to fix problems. Over my many years of experience in lots of facets of the electronics industry, it *seems* like some designs I have run into have been purpose built for a lifespan of "X" whereas the customer would expect "Y" (where X<<Y).

I know there's all the evidence out there from the light bulb consortium at the turn of the century through to the printer ink marketing, I'm just curious about the people who knowingly design this stuff.

[retrolefty]

Interesting question. I can't talk much about electronics products other then their real cost (inflation adjusted) to consumers has never been better. A related consumer product I can relate to is automobiles. Growing up in the 50s it seemed that most middle class+ people would look to replace their car around 3+ years or so. The last two cars I've owned have lasted me 13 and 14 years, they just seem to last longer and are more reliable.

[SirNick]

OTOH, I drive a car that was built ten years before I was born. 

Not in the industry myself, but I see aspects of products where obvious corners were cut.  One can only assume the engineers spec'd parts understanding that they would fail after so many hours of use, and that the part lifetime and warranty period were considered with that in mind.  Or that the user would likely abandon the product anyway, if it failed early.  (LCD TV and monitor PSUs particularly.)

Interestingly, I wandered into a forum thread once where the (unverified but believable) engineer of a brand-name product discussed the statistical analysis of his component choices.  Namely, PSU caps for an amplifier that were operating very close to their rated limits, where you would usually expect to see more safety margin.  The engineer spoke about how the calculated lifespan was "long enough" -- such that they would probably fail about the same time the user would be replacing the unit for other reasons.  I'm not sure if that's planned failure so much as matching a low price point to the cultural trend of throw-away products.

[westfw]

A lot of products are built for an "expected lifetime"; it's not so much that they're specifically designed to "fail early", but they don't get the attention they would need to have a good chance of having a long life...

I've certainly written software that rendered older HW obsolete, usually just by virtue of outgrowing the memory hardware limitations of the old HW.  It wasn't so much intentional, as just something that happens w software.  And I've been on the other side of that as well "how can we pare down this new version so that it will run on the old HW."  But at some point it is VERY MUCH an explicit engineering decision: "This new SW version will NOT run on that old HW."

[miguelvp]

I think the production cost reduction run will be your main culprit. For example, Jeri Ellsworth made a video talking about her C64 FPGA Joystick, and they flew her to China because the thing wasn't working.

Once there she found out they replaced a lot of parts and cut corners, hopefully she was able to save the day and got it working. But what she designed was nothing close to the final product.

But at least it's not like the GM chief engineer that signed off that faulty switch. I still think he was told to sign it or else but it's ok GM named and fired engineers involved because obviously it couldn't be a marketing decision 

[Joule Thief]

aargee, I also spent 25+ years as a service engineer for several manufacturers of medical instrumentation. Most, if not all the disappointments relating to quality have always been "introduced" into the system as a cost saving measure. Most notable was a roller assy for a tubing pump to which a $35 cost reduction was implemented. This was an attractive savings for a system that contained 3 pumps ($100 total savings per instrument in an instrument costing #25,000 USD). Unfortunately the improvement involved hollowing out the individual rollers on the roller cage, allowing the roller to collapse under the strain of the pumping action and eventually compromise the life of the roller.

You guessed it ... either a service call (avg $1000 cost) was needed for mysterious intermittent pumping issues or replacement parts had to shipped over night to the account. Eventually the original design was re-implemented and new rollers were sent to all customers.

The story I tell about my first R&D interview goes like this. First question I was asked was "We have a design choice to make in a transistor used in a power supply assembly", (remember, this is medical instrumentation large enough to require an on site service visit - the unit cannot be shipped back for repair.).

"One transistor costs $3USD and is near its design limits. The other choice is a $7 transistor which will last the life of the unit. Which would you choose? Please take some time to think about your answer before you give it".

My reply was "choose the $7 transistor".

WRONG !!!

"May I explain why I made this choice?"

"If that transistor fails for any reason in the next 15 years (life of system), an onsite service visit will be needed. This will involve buying a plane ticket for $2000 to fly across country on a day's notice, grab a $200 rental car, $300 hotel bill, at least $100 in meals and incidentals, and about a $300 dollar two way round trip for FedEx charges to ship the 50 lb part out overnight freight.  So I say spend the extra $4 to save $2500 cost to the company in service costs."

R&D response was "you are not looking at the bigger picture. We have a price point to bring this system to market and we must hit that mark".

I mumbled something about who is not seeing the "bigger picture" and told the interviewer I could never work for him under those constraints - not with the "bigger picture" I have come to see from working in the field.

Later that year I was paged out to service one of those systems. A "fix it before the sun comes up or get it out of here" scenarios. I met my wife that night. She was a technician at the hospital and saw me working on the system at 2 in the morning and let out a string of curses I can't repeat here.

We have been married going on 35 years now. That's my story and I'm sticking to it. 

[Bored@Work]

I still think he was told to sign it or else

Twenty years ago I would have also thought this. Or that GM management created an atmosphere of fear and obedience where no one dared to step out of line.

But since this was just ten years ago I wouldn't dismiss that the involved engineers just gave a flying fart through a rolling doughnut. The attitude about safety or work ethics in general has massively changed among young engineers.

But back to GM. Even if it was an "I give a fuck" engineer, the management is still responsible. For hiring him, for giving him that responsibility and for not properly supervising him. I.e. for getting everything wrong they are paid for.

[pickle9000]

I'd have to say more about cutting down the BOM bottom line, same effect though.

[miguelvp]

I still think he was told to sign it or else

Twenty years ago I would have also thought this. Or that GM management created an atmosphere of fear and obedience where no one dared to step out of line.

But since this was just ten years ago I wouldn't dismiss that the involved engineers just gave a flying fart through a rolling doughnut. The attitude about safety or work ethics in general has massively changed among young engineers.

But back to GM. Even if it was an "I give a fuck" engineer, the management is still responsible. For hiring him, for giving him that responsibility and for not properly supervising him. I.e. for getting everything wrong they are paid for.

http://www.autonews.com/article/20140605/OEM11/140609881/blame-for-%E2%80%98switch-from-hell%E2%80%99-falls-heavily-on-one-gm

Ironically, it was DeGiorgio who ultimately fixed the part he referred to in a 2002 e-mail as “the switch from hell.” But by the time anyone else in the company figured out what he had done, GM says the switch had cost 13 people their lives.

If he referred to the switch in an e-mail as "the switch from hell" 2 years prior being implemented doesn't that sound like coercion? 10 years or 20 years doesn't matter, look at Enron for example. Let's just say the 2000 decade is not one of our most glorious times, well this decade is not great either, maybe 20/20.

[dannyf]

Or in other words,  knowingly or been forced to fit a design to a life cycle much smaller than customers/end users would expect?

some designs I have run into have been purpose built for a lifespan of "X" whereas the customer would expect "Y" (where X<<Y).

The two are slightly different. The first sounds closer to designing for failure within a set period of time and the 2nd closer to designing for a life of a set period.

ie. "I want the product to fail within a year" vs. "I want the product to last at least a year".

The 2nd approach is wide spread. and it is not common to see the same / similar products at different points that offer different performance (expected life included). Quality is expensive and if a customer expects a life of X, s/he should pay for life of (at least) X.

The 1st approach is rarely seen - it is mean spirited I think.

[dave_k]

I have said this of most contractors/tradies:

"There is no money to be made in fixing the problem, but there is plenty to be made in prolonging it"

[wagon]

I spend my days fixing electronic stuff.  I repair a lot of electric fence energisers : my workshop is in a small city that is a bit of a 'hub' for a lot of agriculture.  Now, I'll get to my point!

I fixed an old unit yesterday, that was over a year older than me.  It was built in 1975.  The main capacitor was still within spec, and the unit really only needed a new 47nF 'X2' cap and a new mains cord/plug.  It could well see the farmer out.  I could have sold him a new one, too.  I don't expect a new one will still be going nearly 40 years from now, since it is a lot more complicated and its little case with its thin walls is likely to suffer in the sun.  Is the new unit built with failure in mind?  I don't think so, but it does have to be sold in a market where the alternative products are, so manufacturing costs must be kept down.  Price is as important as specifications, quite often. 

With a lot of consumer electronics, like TV's, I feel that the 'market' demanded cheaper stuff, and the suppliers worked out that they just weren't selling the better stuff, so they just stopped making it!  Look where that has gotten us, now that we can only get cheap & nasty. 

[digsys]

Sadly, even going back 30-35 yrs, a LOT of companies I contracted R+D for, often paid big bucks for designs that just made it past
their warranty. We got bonus amounts on how close we could get it. In some service departments (who we worked with), they even
ran competitions ! The one big difference to these days was that - There was NO compromise on quality / (design) reliability !
Some of the "fixes" were ingenious :-)   I occasional still get asked, but stopped doing that cr@p a long time ago. It still happens a lot though.

Edit: OK I have to confess.
It was the mid 70s (IIRC), someone had just come up with the idea to connect one of our Monroe calculators (nixie tubes) to a cash drawer !!
It was a gold mine, but they needed to ensure that it had a limited life. I made up the interface card to tie the systems together, which gave the
cashier - items, totals and date - and controlled the cash drawer. I then made up a separate diode logic pcb (100's of diodes from the nixie array)
and set up links to create a "date code". At this point the AND array would latch and turn off the drawer control.
The service techs simply swapped out with the next date code ! I still remember my bestowed hero status ... ahhh memories

[JuKu]

Most manufacturers give a MTBF for their parts. Designers simply pick parts that have a MTBF slightly longer than the warranty period. The EU is looking at requiring appliances to have the lowest MTBF of all components printed on the efficiency rating label.

No, that would mean close to half of the products fail within warranty period! But you are right, mtbf is an important spec, products are not designed to last forever anymore.

When lightbulbs were used, it costed a little more to make them fail. Controlling the impurity of the inert gas costed something, when putting in pure inert gas would make the bulbs last much longer. In Edison museum there are lamps about 100 years old, shining 12 hours a day, 7 days a week.

[Marco]

Red glowing space heaters.

[David Hess]

Comparing the designs for old switching power supplies to new ones reveals a difference even over the past 10 years.

In the past, the filter capacitors were commonly not specified or poorly specified for ripple current rating so they were derated more than strictly necessary to make sure they would have an acceptably long operating life.  Newer switching power supplies use much more precisely rated capacitors so they can be selected for exactly the expected operating life with high accuracy.

[SirNick]

That's just ugly.  Power supplies especially should be designed as the most robust, reliable, and safe module in a system.  At least for consumer electronics, it's usually the one piece most capable of personal or property damage if it fails.  Dirty game.

The story I tell about my first R&D interview goes like this. First question I was asked was "We have a design choice to make in a transistor used in a power supply assembly

One transistor costs $3USD and is near its design limits. The other choice is a $7 transistor which will last the life of the unit. Which would you choose? Please take some time to think about your answer before you give it".

My reply was "choose the $7 transistor".

WRONG !!!

R&D response was "you are not looking at the bigger picture. We have a price point to bring this system to market and we must hit that mark".

Later that year I was paged out to service one of those systems. A "fix it before the sun comes up or get it out of here" scenarios. I met my further wife to be that night. She was a technician at the hospital and saw me working on the system at 2 in the morning and let out a string of curses I can't repeat here.

We have been married going on 35 years now. That's my story and I'm sticking to it.

Aww... they weren't trying to hire you, they were match-making.  <3   

[SeanB]

I bet you were thinking of sending a copy of the total bill to that interviewer along with a line of "Aren't you glad you saved $4 here". Though that might have been better as a message to the shareholders after they got the earnings report.

[David Hess]

The situation with capacitor ripple current specifications over the years reminds me of bridges.

There are Roman bridges still standing and in use after 1500+ hundred years because with a few simple rules of thumb, masonry structures may be easily scaled up.  But those same rules lead to a large derating that is not present in modern structures which are more "efficient" and have a correspondingly short expected operating life.

[SeanB]

Most buildings are conservatively designed ( Tongaat mall excepted from the preceding generalisation) such that they have a very large safety factor built in. This is true for passenger lifts, as the typical spec calls for it to be able to operate, run and level within limits with a load equal to twice the rated load.

[HighVoltage]

Different industry but it just happened:
A friend of mine is in the business to produce flexible exhaust pipes/hoses for a big name truck manufacturer in Germany.
They had to last a minimum of 100,000 km but not more than 150,000 km
His first production batch lasted more than 200,000 km and he lost the contract.
This happened in 2014!

[David Hess]

Most buildings are conservatively designed ( Tongaat mall excepted from the preceding generalisation) such that they have a very large safety factor built in. This is true for passenger lifts, as the typical spec calls for it to be able to operate, run and level within limits with a load equal to twice the rated load.

Sure.  But the Romans designed in safety factors an order of magnitude (or more) larger than a modern structure would use and their static loads were correspondingly large compared to their dynamic loads.  They did not do it deliberately; they just did not know any better and were using a design methodology which they knew from experience to work.

I suspect the same thing happened with aluminum electrolytic capacitors in power supplies.  When they had poorly specified ripple current ratings, large safety factors were used but as those specifications got better, they were not derated as much and operating life was more accurately bounded.

The above may be a justification for over specifying a PC power supply or planning on replacing the capacitors.  I am getting annoyed by how many "high quality" PC power supplies fail just out of warranty because of capacitor failure.

[pickle9000]

Most manufacturers give a MTBF for their parts. Designers simply pick parts that have a MTBF slightly longer than the warranty period. The EU is looking at requiring appliances to have the lowest MTBF of all components printed on the efficiency rating label.

This sounds fair for consumer gear, would be a selling point.

[zapta]

Or in other words,  knowingly or been forced to fit a design to a life cycle much smaller than customers/end users would expect?

I did it recently for an internal software, a hard coded expiration time, because I am sure that by then it will have a upgrade. It will stop functioning at that date but it is not mission critical.

[SirNick]

I was the victim of that, once.  I bought a 24-channel rack-mount audio interface with a PCI interface card.  The drivers had a hard-coded failure date in them.  Worked one day, then the next week, the computer wouldn't boot.  Finally narrowed it down to the PCI card -- when it was removed, the PC booted fine.  Logically, I expected the card had gone tango-uniform and threw it away.

Then, while looking for a replacement, I found a forum post where a BUNCH of other people just happened to be having the exact same problem.  The company released new drivers that "fixed the problem" shortly (at most a couple days) after.  Luckily, I had just tossed the card into a junk box to get rid of later, so I was able to upgrade the drivers, reinstall the card, and get on with life.  But I can imagine, if I were running a small commercial studio and that was my primary rig...

Bomb dates are NOT COOL, ever, but especially if you don't know they're there.

[hamdi.tn]

Crucial subject and i think it concern not only EE but every discipline that involve both Engineers and decision makers and it kind of remind my boss. The quality of a particular design now is defined by a commercial challenge to keep cost as low as possible, even if it doesn't mean that those product are cheap, just astronomic profits for the company. Most of the time engineer, forced to keep there jobs, accept to give some rubbish design just to satisfy the boss greed.
I remember when Dave talked about PICKIT3 and how crap it is and some wireless energy harvesting device totally useless and both driven by a commercial consideration not technical consideration.
I still enjoy the vintage video, like everyone in this blog i think, just because it remind me that designing was the job of defeating engineering challenge and give the customer some robust, reliable piece of hardware that last for ever , i had a German tv that run for 25 years everyday no problem at all.
An other thing i think is the nature of the market it self, costumer now are hungry for technology and new gadget that came up everyday so there no need any more for a product that last more then 5 years, the user will not use his device for more than that anyway.

[miguelvp]

I remember when Dave talked about PICKIT3 and how crap it is ...

I loved Microchips response:

[zapta]

I loved Microchips response:

Well done damage control.  Humility on one hand, promoting the new product on the other, and a surprise ending when they reveal the first name of Mr. Head. Somebody at Marketing should get a bonus.

[wraper]

I was the victim of that, once.  I bought a 24-channel rack-mount audio interface with a PCI interface card.  The drivers had a hard-coded failure date in them.
Bomb dates are NOT COOL, ever, but especially if you don't know they're there.

Ulikely that was intentional. Similar thing with Crucial M4 SSD
http://www.storagereview.com/crucial_m4_0309_firmware_update_for_5200_hour_bug_released
100% of that model SSD were affected.

[tszaboo]

But since this was just ten years ago I wouldn't dismiss that the involved engineers just gave a flying fart through a rolling doughnut. The attitude about safety or work ethics in general has massively changed among young engineers.

Sadly, I have to agree. I have to say too many times to the collegues other people working in the same building: That is not according to IPC-610 (Acceptability of Electronic Assemblies). Most response I usually hear makes me lose all hope in humanity.

[hamdi.tn]

Can't blame young engineer for that ( am young  ) my boss was a professor in an engineering school and the only thing he care about MONEY, to hell engineering. He ordered the production of 100 unit of equipment we produce that time ( energy saving equipment ) for a total cost of around 100.000$ the product still under-test and showing major dysfunction, ignoring my advice and production manager advice and sell the thing anyway... every one of them returned as defective in 2 month 
and that's how he teach engineering 

[hamdi.tn]

Most response I usually hear makes me lose all hope in humanity.

still, i have to agree with that, when i ask young engineer or engineering student why they choose to be EE, i lose all hope in humanity indeed  ... most common answer " to make money more than anyone else " ... and they get big disappointment once they finish school as much as they are a big disappointment to the industry

[Tinkerer]

Can't blame young engineer for that ( am young  ) my boss was a professor in an engineering school and the only thing he care about MONEY, to hell engineering. He ordered the production of 100 unit of equipment we produce that time ( energy saving equipment ) for a total cost of around 100.000$ the product still under-test and showing major dysfunction, ignoring my advice and production manager advice and sell the thing anyway... every one of them returned as defective in 2 month 
and that's how he teach engineering 

At the company I work at I am sometimes amazed at what makes it out the door. One new product, 18 months behind schedual and it was hell trying to get the thing to work and they are rushing to sell it when in reality the thing should probably still have been in the prototype stage. Another product basically had a major fault that is only now getting addressed, this is something like a couple years after it was first created; I suppose they should be lucky they havent sold very many. Obviously alot of stuff that is sold does actually work but its just in some things nothing goes right.

Heres an example for ya. Friend has a garage door that wouldnt open. The cause? Well the one piece that should have been made of tough material was instead one of those cheap white plastic gears. The teeth all stripped away. Aside from that, worked perfectly.

Another example I have seen in a crt monitor was an electrolytic cap placed practically right next to one of the power resistors. These resistors had become hot enough to discolor the board and one of them(it wasnt as close to the cap as the other but having 3 hot resistors close to each other certainly didnt help with heat disappation) had even baked most of the writing off itself from continued heating. This cap was connected directly to one of the control chips. Here is the kicker, just a couple inches away was perfectly good board space that could have been used as the location for this cap, it wouldnt have interfered with traces or anything to have moved it over a few inches; had someone decided to during the design phase, moving that cap could have been considered a minor change.

still, i have to agree with that, when i ask young engineer or engineering student why they choose to be EE, i lose all hope in humanity indeed  ... most common answer " to make money more than anyone else " ... and they get big disappointment once they finish school as much as they are a big disappointment to the industry

Who in the world is that? You dont go into engineering to make lots of money.(even though you will likely live comfortably) If I had wanted to make money, I would have gone into politics or something like banking/wallstreet.

[SirNick]

I was the victim of that, once.

Ulikely that was intentional. Similar thing with Crucial M4 SSD

I have wondered, because I don't know what they could possibly stand to gain.  (Drivers are a free download, there's no subscription model or anything.)  But, what reason does a kernel driver have to know the date and time?  Puzzling.

[NiHaoMike]

I suspect the same thing happened with aluminum electrolytic capacitors in power supplies.  When they had poorly specified ripple current ratings, large safety factors were used but as those specifications got better, they were not derated as much and operating life was more accurately bounded.

The above may be a justification for over specifying a PC power supply or planning on replacing the capacitors.  I am getting annoyed by how many "high quality" PC power supplies fail just out of warranty because of capacitor failure.

I think the main problem is the "smart" fan controller they put into many PSUs nowadays, marketing it as a feature. And then there's active PFC, which actually is useful in commercial settings, but in residential, it's just an extra cost and extra point of failure. I once opened up a broken laptop PSU and found out that it failed because the PFC stage failed. Swap that out for a plain voltage doubler and it works just fine, albeit without universal input capability.

[aargee]

Well and then there's this:

Engineers' Creed

As a Professional Engineer, I dedicate my professional knowledge and skill to the advancement and betterment of human welfare.

I pledge:

To give the utmost of performance;
To participate in none but honest enterprise;
To live and work according to the laws of man and the highest standards of professional conduct;
To place service before profit, the honor and standing of the profession before personal advantage, and the public welfare above all other considerations.
In humility and with need for Divine Guidance, I make this pledge.

Adopted by National Society of Professional Engineers, June 1954

- See more at: http://www.nspe.org/resources/ethics/code-ethics/engineers-creed#sthash.fQvUZCa0.dpuf

Even though this is an US site, most Engineering bodies around the world something similar as a creed. It is still quoted and still current.

Which puts an interesting slant on all those who rant and rave about who is entitled to use the title of Engineer - or not. It essentially says to be an Engineer you must firstly stand by the morals/ethics of the profession over the $$$.

As an engineer in today's world our response would be "For God's sake man would you have us starve to death?"
Really? Should we walk away from dodgy design implementations?

[hamdi.tn]

Who in the world is that? You dont go into engineering to make lots of money.(even though you will likely live comfortably) If I had wanted to make money, I would have gone into politics or something like banking/wallstreet.

well, where am from (Tunisia) the best salaries go for Doctors, lawyers then engineers. So basically if you are an engineer you have a chance of getting a good salary compared to most people in industry, around 750 USD for graduated engineer/ 1k$ to 1.5k$ for senior / and this go up to 2.5k$ for manager) while  everyone else in the industry earn between 250$ and  450$.

Politics here are not profitable ( in a legal way ) unless you are the president and get 20.000$ / month  .. bastard , anyway I don't think i can consider politics a "job" anywhere in the world.

[hamdi.tn]

To participate in none but honest enterprise;

honest enterprise ... really... 

[wagon]

Another example I have seen in a crt monitor was an electrolytic cap placed practically right next to one of the power resistors. These resistors had become hot enough to discolor the board and one of them(it wasnt as close to the cap as the other but having 3 hot resistors close to each other certainly didnt help with heat disappation) had even baked most of the writing off itself from continued heating. This cap was connected directly to one of the control chips. Here is the kicker, just a couple inches away was perfectly good board space that could have been used as the location for this cap, it wouldnt have interfered with traces or anything to have moved it over a few inches; had someone decided to during the design phase, moving that cap could have been considered a minor change.

A common (here in Australia) fire alarm 24V power supply / charger has a similar problem.  They put a little (100nF??) polyester cap next to a 5W resistor that runs hot all of the time.  The little cap doesn't respond well to this, eventually  failing and causing the regulator to not regulate anymore.  A shame, since the design is quite nice otherwise : it has a conventional transformer with a switchmode regulator (so 40V in, ~24vDC out).    I relocate the cap on longer legs so it lasts longer.

[dannyf]

to make money more than anyone else

You should be thankful of that - without it, we would still be living in caves.

[cimmo]

to make money more than anyone else

You should be thankful of that - without it, we would still be living in caves.

Why do you have to ruin interesting threads by throwing in your political opinions all the time?

[mzzj]

When lightbulbs were used, it costed a little more to make them fail. Controlling the impurity of the inert gas costed something, when putting in pure inert gas would make the bulbs last much longer. In Edison museum there are lamps about 100 years old, shining 12 hours a day, 7 days a week.

This same myth keeps running around. Guess what is the effiency of those ancient edison bulbs??
Advanced quiz: guess what is the optimium lifetime of lets say 100 W incandescent bulb considering typical bulb purchase price, effiency and electricity bill?

[zapta]

Which puts an interesting slant on all those who rant and rave about who is entitled to use the title of Engineer - or not. It essentially says to be an Engineer you must firstly stand by the morals/ethics of the profession over the $$$.

We should develop a similar creed for electronic parts distributors. This way we will get free parts from Digikey.

[SirNick]

Nothing is that polarized in reality.

Obviously a company needs to make a profit, or else there are no products.  But there's enormous pressure from the customer to make it better faster cheaper, with opposing pressure from the employees for better pay, more tools, etc.  At the same time, margins are getting cut from retailers as the consumer has more ability to compare prices from ANY source world-wide instead of just the authorized dealer in their home town.  As such, retailers want steep discounts for large orders, or whatever they can get to set them apart.  Of course, consumers are also being trained that they can and should return the product for any reason whatsoever -- including insufficient pre-sales research, or whim, or buyer's remorse, or finding a cheaper price elsewhere.

So, yeah there's good old fashioned greed involved, sure.  But there's also the monster of our own making:  "Why isn't anything built to last anymore?  Also, I can get this $15 cheaper from Amazon, and $30 cheaper from a no-name source on eBay."

OTOH, we're willing to pay ridiculous prices to see a movie or watch a basketball game...

[wagon]

Nothing is that polarized in reality.

Obviously a company needs to make a profit, or else there are no products.  But there's enormous pressure from the customer to make it better faster cheaper, with opposing pressure from the employees for better pay, more tools, etc.  At the same time, margins are getting cut from retailers as the consumer has more ability to compare prices from ANY source world-wide instead of just the authorized dealer in their home town.  As such, retailers want steep discounts for large orders, or whatever they can get to set them apart.  Of course, consumers are also being trained that they can and should return the product for any reason whatsoever -- including insufficient pre-sales research, or whim, or buyer's remorse, or finding a cheaper price elsewhere.

So, yeah there's good old fashioned greed involved, sure.  But there's also the monster of our own making:  "Why isn't anything built to last anymore?  Also, I can get this $15 cheaper from Amazon, and $30 cheaper from a no-name source on eBay."

OTOH, we're willing to pay ridiculous prices to see a movie or watch a basketball game...

Well said....

[saturation]

Most reputable makers can design obsolescence rather than failure and there is full disclosure to the buyer, such as a consumable part that has no replacement, e.g. batteries, chemical sensors.   

In the USA, putting a purposed defect into devices would give the brand a bad name as the failure could occur anytime,  it would make a warranty impossible,  most distributors who warrant a device for 1-2 weeks after a sale would probably not sell it, and if consumers are misled it could lead to a class action lawsuit or even a criminal liability through the attorney general.

[wagon]

The upside is you can choose to keep that good stuff until it's worn out, many years later if you so desire.

[con-f-use]

Japanese manufacturers have a different way of keeping the sales coming. They build high quality products that last, but every year release new models with new features that make people want to upgrade. You often see people discarding perfectly good, fully working electronics, often in the original box in Japan. A new one with a new widget came out so they replaced it.

Japanese shops are set up for low margins but high volume too. They will stick not just every model of computer mouse or washing machine, but every available colour too. They keep them in stock so you can get instant gratification. Somehow they managed to make a €300 rice cooker an impulse purchase.

And look how Japanese economy is doing.

Of course your statement is not the reason why Japan is struggling. I agree that new features and constant improvement is the best way to ensure sales, but Japanese stores might not be the best example.

[SirNick]

Japanese manufacturers have a different way of keeping the sales coming. They build high quality products that last, but every year release new models with new features that make people want to upgrade. You often see people discarding perfectly good, fully working electronics, often in the original box in Japan. A new one with a new widget came out so they replaced it.

Interestingly, we're seeing consumer acceptance cycles shorten to the point that even today's built-to-a-price products are out-living their value.  The mobile phone market is especially interesting:

On one hand, I have an iPhone 4.  Pretty respectable hardware, but after installing iOS 7, it feels unacceptably clunky.  Is the added weight of the new OS a justified trade-off for whatever it's doing that iOS 6 wasn't?  (IMO, no -- I would gladly go back.)  Is it just laziness?  (CPU power to burn, so why optimize?)  Or is it merely a shrewd tactic to sell newer phones?  It seems kinda sad that even new, fast hardware is burning more battery power than it might ought to.

Then on the other hand, you have Amazon's new Fire Phone.  Spec-wise, it's a solid offering.  But the Internet's collective impression:  "Meh.  Nothing new."  I don't even think the public knows what it was hoping for, they're just not impressed.  I think it's because we've reached a saturation point where there isn't much room to improve the hardware anymore -- at least not every year.  Not that they aren't trying to fake it.  LG just released a new phone with "4x HD resolution"... 2560x1440 in a 5.5" display.  The DPI is starting to creep into the realm of print media.  Does that really do any good?  Flogging a horse, IMO.  But, I guess we can't have consumers using the same phone for four years.  No sir.

[miguelvp]

Interestingly, we're seeing consumer acceptance cycles shorten to the point that even today's built-to-a-price products are out-living their value.  The mobile phone market is especially interesting:

...

But, I guess we can't have consumers using the same phone for four years.  No sir.

I'm happy with my Blackberry 9900. Only 3 years old but it doesn't have a single scratch and works as well and as fast as day one. But I don't use my phone to play games

Then again, see what not having obsolescence is doing to RIM.
 

[SirNick]

RIM is a special case, I think.

If I had to guess, I would pin at least part of the blame on the Blackberry Enterprise Server licensing model.  When you have the option of paying $$$ per seat for mobile email access, or connecting an iPhone / Android to your Exchange server for free, well.... *shrug*

I'm sure the long-term usability of the phone does prolong the life for the casual user (BB fans tend to be a loyal bunch), but if you've been the one responsible for provisioning new phones in a corporate environment, you'll see that CxOs are the consumer-iest of the consumers when it comes to being the first kid to have a new toy.    Theirs always seemed to start "acting up" a lot when a new model got released.

[miguelvp]

I've always been able to connect my phone to my many e-mails including work's Exchange without the need for the Enterprise Server. I can accept meetings and it's all in my calendar. Never saw what value the Enterprise Server brought, maybe it allows you to do more things, but you never had to pay just to connect it to an e-mail address.

I have 9 e-mail addresses and text messages going to the same inbox. Of course I can view them separately

[ejeffrey]

I have wondered, because I don't know what they could possibly stand to gain.  (Drivers are a free download, there's no subscription model or anything.)  But, what reason does a kernel driver have to know the date and time?  Puzzling.

There is practically no failure pattern so bizarre that it can't be the product of an unintentional bug.  The standard example is the 500 mile email.  There are plenty of reasons why a driver for a multi-channel audio interface might do something with date/time.  There are smart things, like keeping track of time stamps for audio streams, or dumb things like logging how old the firmware build is when the driver is loaded (oops, the firmware version is 1000 days old, but we only have a 3 digit field!).

[T3sl4co1l]

Time is a weird thing... the Patriot missile system had a peculiar bug where its clock would drift out of sync and lose tracking by the same distance.  Now, why they'd ever need to use disparate clocks in the damned thing to begin with, I have no idea... design by committee?  More lessons to avoid.

Tim

[bwat]

Time is a weird thing... the Patriot missile system had a peculiar bug where its clock would drift out of sync and lose tracking by the same distance.  Now, why they'd ever need to use disparate clocks in the damned thing to begin with, I have no idea... design by committee?  More lessons to avoid.

Tim

Looks like it was a problem with different representations of time in the software and they mixed them when subtracting: the subtrahend in one representation, the minuend in the other. I got this from: http://www.ual.es/~plopez/docencia/itis/patriot.htm. I have the "clock drift of 57 us/minute" reason cited in a book [But], but I think the linked paper has a more plausible reason.

[But] Giorgio C. Buttazzo. Hard Real-time Computing Systems. Kluwer, 1997

[SeanB]

Many years ago when cellular phones were both new and expensive we gave our bike messenger a Panasonic phone. Due to the nature of SA driving the bike regularly was involved in accidents, and one day of course we got the call that he had come off it and hit something. The phone was the point of contact, with the only protection being his suit pants pocket between it and the road as he slid down it to a stop. We sent it into Panasonic, and it was repaired. The only parts that they kept of the old phone were 8 small screws, the entire phone was replaced with new parts aside from these screws. IIRC this was about $20 cheaper than a new phone at the time.

[SirNick]

There are plenty of reasons why a driver for a multi-channel audio interface might do something with date/time.  There are smart things, like keeping track of time stamps for audio streams, or dumb things like logging how old the firmware build is when the driver is loaded (oops, the firmware version is 1000 days old, but we only have a 3 digit field!).

Duh, of course... SMPTE time codes.  I'm sure those make it to the kernel driver level on that kind of interface.  It had a lot of intelligence in the PCI card to control multiple modular interfaces and such.  Time sync would be essential between interfaces.  I clearly didn't think that statement through before posting.

I actually really like that screen, and although it isn't much of a step up from full HD it is noticeable.  Forget all the nonsense Apple put out about "retina" displays and the limits of human eyes. Having a super high resolution display means you can scan web pages when zoomed out, rather than zooming in and scrolling.  Your brain only needs word shapes to get a vague sense of the content. It's handy for PDFs too.

OK, that's fair.  I guess I'll withhold judgement until I try it.  Apple marketing notwithstanding, I find my phone's screen sufficiently detailed to cause eye-strain before running into issues with inadequate resolution.  Now the 5.5" of screen real-estate may be genuinely useful.  (Although I'm more interested in something small than something with an expansive screen.  For that, I have a tablet or computer.  To each his own.)

There are still useful features being added to phones. NFC is getting more and more useful, and always-available voice control handy. Indoor navigation (not using GPS) has also improved a lot in the last few years.

No argument there -- we're not quite done yet.  However, I do think we're a while away from revolutionary changes the likes of the BlackBerry, iPhone 1, etc.  Yet, people still expect something new that will blow them away every release cycle, with the inevitable disappointment of "merely" incrementally improved hardware.

[Richard Crowley]

You COULD make a notebook computer that would last 20 years. Buy why WOULD you do that?
The market for consumer computers with a 20-year expected life cycle is essentially zero.
It is quite likely that the "notebook" form-factor won't even exist (or be remembered) in 20 (or even 10) years.

[SirNick]

Sure it will.  My oldest brother had an 8088 laptop in college.  That was something like 25 years ago, and they're still prevalent today.  Until technology somehow makes keyboard input a thing of the past, it's a form-factor that can't be beat for portable computers.

[David Hess]

You COULD make a notebook computer that would last 20 years. Buy why WOULD you do that?
The market for consumer computers with a 20-year expected life cycle is essentially zero.
It is quite likely that the "notebook" form-factor won't even exist (or be remembered) in 20 (or even 10) years.

I doubt the notebook/laptop form factor will be going anywhere because it serves as a portable replacement for the desktop with a keyboard and monitor.  The market will be smaller because people who only consume data can get by with tablets but it will still be large enough to support itself.

As far as laptops, what I want is something that is ruggedized, takes standard batteries, has a matte screen, and no chiclet keyboard even if it has to be thicker and heavier.

[luky315]

I once had to use 85°C Electrolytic capacitors and not 105°C parts because "management" thought they would last longer then the warranty period and that is long enough.

[wagon]

I once had to use 85°C Electrolytic capacitors and not 105°C parts because "management" thought they would last longer then the warranty period and that is long enough.

The best way to deal with this is to trap management into demanding something too cheap and creating a lot of in-warranty failures. Once they have been burned and maybe one of them made into a scapegoat they will listen to you next time.

You and I both know that's not how it works in the real world.  The turds who demand the cheaper parts will destroy you to save their own skins..... better to argue the point and win before the product goes to market.

[David Hess]

I once had to use 85°C Electrolytic capacitors and not 105°C parts because "management" thought they would last longer then the warranty period and that is long enough.

The best way to deal with this is to trap management into demanding something too cheap and creating a lot of in-warranty failures. Once they have been burned and maybe one of them made into a scapegoat they will listen to you next time.

They will just argue that it is your fault for not being persuasive enough.

[wagon]

I once had to use 85°C Electrolytic capacitors and not 105°C parts because "management" thought they would last longer then the warranty period and that is long enough.

The best way to deal with this is to trap management into demanding something too cheap and creating a lot of in-warranty failures. Once they have been burned and maybe one of them made into a scapegoat they will listen to you next time.

They will just argue that it is your fault for not being persuasive enough.

You can't win against management ar$eholes, salesmen & accountants.

[Refrigerator]

Well, as a hobbyist who gets 90% of his electronics parts while dumpster diving i can't complain, the sooner the failure, the newer the parts i get.  After that i can can use those parts to repair my broken electronics.

[Phaedrus]

My company wants to sell a non-UL certified (or certifiable!) power supply that is so poorly designed it presents immediate danger to life and limb. My report and analysis basically amount to, "This product cannot legally be sold in the US, and even if it could, we shouldn't sell it, and if we do it anyway we will regret it when we suffer a million dollar lawsuit." I can't even use my lab right now because one of the samples burned, and I don't want to inhale cadmium fumes (it's non-RoHS as well).

Let's see if common sense prevails. My resume is being sent out this weekend regardless. If anyone's got an electronics technician job in SoCal available let me know.

[SirNick]

Curious... Was that the product of cheapskating, or merely a poor design?

[Phaedrus]

Curious... Was that the product of cheapskating, or merely a poor design?

Someone reverse engineered an ATX 1.3 PSU, probably an FSP or Antec, from the late 90s. Then they started removing parts experimentally until every part not required to turn on was removed. Then they put it in the cheapest possible housing on the cheapest PCB with the cheapest parts possible.

BOM cost is probably under $7/unit. I'd be impressed if it wasn't a lethal hazard to the operator. Seriously--there are holes on the underside of the unit near the primary section that are large enough for a screwdriver or a careless finger to fit through. And that's just the beginning.

I've tested hundreds of models of ATX PSU, including some really nasty ones I found in night markets in Taipei, and this unit is probably the worst I've ever tested. And they want to sell it here.

[wraper]

You and I both know that's not how it works in the real world.  The turds who demand the cheaper parts will destroy you to save their own skins..... better to argue the point and win before the product goes to market.

That's actually the best possible outcome. You will of course have saved every email and document you wrote pointing out how badly things were about to go wrong. You can then take them to an employment tribunal, win and get a free all expenses paid year off work and a glowing recommendation for your next position.

In fantasies... Only rare one will want to hire someone who goes against the system and collects evidence instead of doing a fucking job.

[Sigmoid]

"If that transistor fails for any reason in the next 15 years (life of system), an onsite service visit will be needed. This may involve me buying a plane ticket for $2000 to fly across country on a day's notice, grab a $200 rental car, $300 hotel bill, at least $100 in meals and incidentals, and about a $300 dollar two way round trip for FedEx charges to ship the 50 lb part out overnight freight.  So i say spend the extra $4 to save $2500 cost to the company in service costs."

R&D response was "you are not looking at the bigger picture. We have a price point to bring this system to market and we must hit that mark".

I mumbled something about who is not seeing the "bigger picture" and told the interviewer I could never work for him under those constraints - not with the "bigger picture" I have come to see from working in the field.

Later that year I was paged out to service one of those systems. A "fix it before the sun comes up or get it out of here" scenarios. I met my further wife to be that night. She was a technician at the hospital and saw me working on the system at 2 in the morning and let out a string of curses I can't repeat here.

We have been married going on 35 years now. That's my story and I'm sticking to it.

So you were introduced to the love of your life by a cheap component? It seems they ARE good for something after all.

[wagon]

"If that transistor fails for any reason in the next 15 years (life of system), an onsite service visit will be needed. This may involve me buying a plane ticket for $2000 to fly across country on a day's notice, grab a $200 rental car, $300 hotel bill, at least $100 in meals and incidentals, and about a $300 dollar two way round trip for FedEx charges to ship the 50 lb part out overnight freight.  So i say spend the extra $4 to save $2500 cost to the company in service costs."

R&D response was "you are not looking at the bigger picture. We have a price point to bring this system to market and we must hit that mark".

I mumbled something about who is not seeing the "bigger picture" and told the interviewer I could never work for him under those constraints - not with the "bigger picture" I have come to see from working in the field.

Later that year I was paged out to service one of those systems. A "fix it before the sun comes up or get it out of here" scenarios. I met my further wife to be that night. She was a technician at the hospital and saw me working on the system at 2 in the morning and let out a string of curses I can't repeat here.

We have been married going on 35 years now. That's my story and I'm sticking to it.

So you were introduced to the love of your life by a cheap component? It seems they ARE good for something after all.

I met my future wife after  discussion about why it cost $100 to replace a 40cent part..... in my case, an electrolytic. It happens!

[XFDDesign]

In fantasies... Only rare one will want to hire someone who goes against the system and collects evidence instead of doing a fucking job.

Which is why I'm pretty sure I'll be getting the Axe come the December Layoffs.

My day job has me working on a part for the medical space.
This part, has some serious problems.
Design is saying it's not a big deal (I'm an apps engineer), and it'll only affect a "small" number of customers who will then simply not use our part.
Marketing is simply holding up the rug while the designers sweep the problems under it.

Lucky me, my role has at least the authority to stop release until I'm happy (or fired and replaced with someone else).

[wagon]

I was thinking about this some more today.  A bad habit of some is putting batteries like nicad or NiMH on a PCB. The battery leaks at about the ten year mark, about a year after all parts are obsolete.

[David Hess]

Batteries are always a problem; either they have to be soldered in or use a relatively unreliable mechanical connection.  Parts with integrated batteries like non-volatile memories are even worse.

It gets even worse when the battery is used to backup critical information like firmware stored in SRAM, calibration constants, or purchased options.

[wagon]

Batteries are always a problem; either they have to be soldered in or use a relatively unreliable mechanical connection.  Parts with integrated batteries like non-volatile memories are even worse.

It gets even worse when the battery is used to backup critical information like firmware stored in SRAM, calibration constants, or purchased options.

Mounted off-board is a better way of doing it, if you must have a backup battery, so if it leaks the damage is largely contained. (although, I have seen corrosion 'wick' its way along wires then rotting the pcb.)

[macboy]

In Edison museum there are lamps about 100 years old, shining 12 hours a day, 7 days a week.

Those old lamps run relatively cooler, dramatically improving lifetime at the expense of much lower efficiency. That's why Halogen bulbs were invented; running the filament hotter improves efficiency (less IR/heat output, more visible light output) but would have quickly evaporated the filament, prior to Halogen technology.

[wagon]

In Edison museum there are lamps about 100 years old, shining 12 hours a day, 7 days a week.

Those old lamps run relatively cooler, dramatically improving lifetime at the expense of much lower efficiency. That's why Halogen bulbs were invented; running the filament hotter improves efficiency (less IR/heat output, more visible light output) but would have quickly evaporated the filament, prior to Halogen technology.

But how do the facts fit in around the conspiracy theory?

[Refrigerator]

In Edison museum there are lamps about 100 years old, shining 12 hours a day, 7 days a week.

Those old lamps run relatively cooler, dramatically improving lifetime at the expense of much lower efficiency. That's why Halogen bulbs were invented; running the filament hotter improves efficiency (less IR/heat output, more visible light output) but would have quickly evaporated the filament, prior to Halogen technology.

But how do the facts fit in around the conspiracy theory?

Illuminati ?

[wagon]

Illuminati ?

It's a good thing I'm wearing my tinfoil hat then.

[SeanB]

I actually have a few of those lamps, and they are very long lasting. Only have had one fail in 20 years, and that was because it was dropped and the glass broke.

[ciccio]

I recently had a discussion with a customer about the "longevity" of the equipment he is still building and selling.
I've been responsible for the design of these products for the last 15 years, after he bought the small company that was his supplier, and that was closing because the owner wanted to retire.
The products are audio amplifiers and mixer for PA system, mostly installed in churches, and there are more than 1000 systems installed.
The oldest  are about 40 years in service, and most of the failures come from broken mic cables or lightning strikes during summer thunderstorms (a church audio system, with 100 V speaker lines and mic cables, acts as a big lightning attractor).
The problem is that, with the oldest systems in service , the risk that one of the units burst "naturally" into flames increases every year (I must admit that they are an example of REALLY CONSERVATIVE design, but there is a limit to the life of every component).
Most of them are installed in historical buildings, and this risk of fire propagating to the building structure or furniture is high (Installation standards were not really strict, in these times) .
He asked me to design something that will break after a certain amount of time (let's say 5 years), and will require an exchange of the equipment.
The "breaker" shall be a device that is proprietary and not available to external technicians, so an house-call will be required.
This will allow to check the equipment status, upgrade it to the latest version, and have it ready for other 5 years of service.
As a secondary effect, it will generate some money from maintenance work.

I thought a little about the question, and asked the customer to proceed in another direction (e.g. contact the customers to explain that their system require preventive maintenance), but I'm still puzzled by the problem.

I know that similar things are programmed into industrial equipment, or software programs, but I'm asking if other members think that this is "legal" or "moral".....

Best regards

[jancumps]

Conspiracy part two
Down here, the canonical example given for intentional failure is the TL (fluorescent tube) lamp of Philips.
The gossip mill keeps saying (for 40+ years I think) that the initial design was modified because its life span was too long.
Of course I'm not backed up by any facts.

[wagon]

Conspiracy part two
Down here, the canonical example given for intentional failure is the TL (fluorescent tube) lamp of Philips.
The gossip mill keeps saying (for 40+ years I think) that the initial design was modified because its life span was too long.
Of course I'm not backed up by any facts.

There maybe some merit in this one.  My house has tubes up that are probably as old as the hose, and the house was built in the late 1960's. I changed the tube in my kids room yesterday, and it was an old 40w unit.  The new tube is so much brighter though!

[SeanB]

Simple reason the TL does not last as long as the old T12 tube is that it is likely the old T12 tube was a full dose tube, with probably 100mg of mercury inside the tube so it would not go mercury starved over it's lifetime, and would only degrade due to heater losing emission and the phosphor aging. They typically will last 10 years on a magnetic IS ballast, or around 8 years on a pulse start ballast as there the cathodes get stripped faster. Newer T8 tubes have a lower mercury dose, 12mg or less, and the typical Alto ( what a good word, they stop working fast) has under 4mg, so that you do not have to dispose them as hazardous waste. That the tube typically lasts 2 years or less, degrades fast lumen wise and you need 6 relamps to meet the old T12 is not considered.

This is for tubes made by a reputable manufacturer in a plant with good process control, cheap tubes made in a OHL plant with pretty much QC being " did at least half work in the box? Ship the box" are lot going to reach much past a year.

I find the tubes made in Poland are the best of current, Hungary, then Russia ( strange that), the odd old batch from France and then of the far east Indonesia, Thailand and bottom of the barrel China. Then you get the tubes with no country of origin. I have only had one outlier of the cheapies, a Ya Ming tube that did 8 years, long survivor of the rest of the box of 25 that all lasted less than a year, typically failing in 6 months.

[Fsck]

I once had to use 85°C Electrolytic capacitors and not 105°C parts because "management" thought they would last longer then the warranty period and that is long enough.

The best way to deal with this is to trap management into demanding something too cheap and creating a lot of in-warranty failures. Once they have been burned and maybe one of them made into a scapegoat they will listen to you next time.

They will just argue that it is your fault for not being persuasive enough.

You can't win against management ar$eholes, salesmen & accountants.

if you create enough of a papertrail, you can win. avoid in-person and phone interactions at all costs.

[Refrigerator]

Simple reason the TL does not last as long as the old T12 tube is that it is likely the old T12 tube was a full dose tube, with probably 100mg of mercury inside the tube so it would not go mercury starved over it's lifetime, and would only degrade due to heater losing emission and the phosphor aging. They typically will last 10 years on a magnetic IS ballast, or around 8 years on a pulse start ballast as there the cathodes get stripped faster. Newer T8 tubes have a lower mercury dose, 12mg or less, and the typical Alto ( what a good word, they stop working fast) has under 4mg, so that you do not have to dispose them as hazardous waste. That the tube typically lasts 2 years or less, degrades fast lumen wise and you need 6 relamps to meet the old T12 is not considered.

This is for tubes made by a reputable manufacturer in a plant with good process control, cheap tubes made in a OHL plant with pretty much QC being " did at least half work in the box? Ship the box" are lot going to reach much past a year.

I find the tubes made in Poland are the best of current, Hungary, then Russia ( strange that), the odd old batch from France and then of the far east Indonesia, Thailand and bottom of the barrel China. Then you get the tubes with no country of origin. I have only had one outlier of the cheapies, a Ya Ming tube that did 8 years, long survivor of the rest of the box of 25 that all lasted less than a year, typically failing in 6 months.

I have a 40-year old russian radio that uses tubes, a couple years back one of the tubes failed but i happened to find a bag of the same kind of tubes thrown away, found one that fits, popped it in and it worked flawlessly, i can listen to  retro music again.
I was lucky to find those tubes because they cost a pretty penny over here where i live ( 40 bucks a pop! ).

[SirNick]

The problem is that, with the oldest systems in service , the risk that one of the units burst "naturally" into flames increases every year ....  Most of them are installed in historical buildings, and this risk of fire propagating to the building structure or furniture is high (Installation standards were not really strict, in these times) .
He asked me to design something that will break after a certain amount of time (let's say 5 years), and will require an exchange of the equipment.
The "breaker" shall be a device that is proprietary and not available to external technicians, so an house-call will be required.
This will allow to check the equipment status, upgrade it to the latest version, and have it ready for other 5 years of service.
As a secondary effect, it will generate some money from maintenance work.

I thought a little about the question, and asked the customer to proceed in another direction (e.g. contact the customers to explain that their system require preventive maintenance), but I'm still puzzled by the problem.

That IS a tough one.  From my experience working with / in / around that kind of organization (be it a church, school, or non-profit org), there is very little attention given to maintenance and preventative replacement.  It's often a shoe-string budget, with no one really filling the role of lifecycle analyst, which pretty much guarantees that anything not strictly necessary will be put off until becomes strictly necessary.  And then, if it can be bodged, it will be.

Still, 5 years seems a little short -- short enough that it would still be memorable to anyone there.  "It's broke again?  Didn't we JUST get this thing fixed a few years ago?"  It also depends on how expensive that service call is.  Labor isn't cheap, and if you make an amp that takes $300 to service every five years, the owner is better off replacing it with an off-the-shelf Class D model that he can source at Guitar Center within half an hour of the failure.

Up-front service contracts might be an option -- that way, it's pre-paid, so there's no struggle over wrangling the funds when maintenance is due.  OTOH, if it isn't mandatory, it won't be purchased most of the time.  If it IS mandatory, many of your clients will go elsewhere.

I'm sure I'm repeating discussions you've already had with yourself and your boss at this point.

[David Hess]

The problem is that, with the oldest systems in service , the risk that one of the units burst "naturally" into flames increases every year (I must admit that they are an example of REALLY CONSERVATIVE design, but there is a limit to the life of every component).
Most of them are installed in historical buildings, and this risk of fire propagating to the building structure or furniture is high (Installation standards were not really strict, in these times) .
He asked me to design something that will break after a certain amount of time (let's say 5 years), and will require an exchange of the equipment.
The "breaker" shall be a device that is proprietary and not available to external technicians, so an house-call will be required.
This will allow to check the equipment status, upgrade it to the latest version, and have it ready for other 5 years of service.
As a secondary effect, it will generate some money from maintenance work.

I think it is a monumentally stupid idea.  What if the "breaker" is the first thing to fail?  What if a customer figures out how to bypass it thereby creating a larger safety issue?

If the device has an increasing risk over time of suffering catastrophic failure which could spread, then design in safety in depth.  Typically this involves metal shielding, fusible links, and fire resistant materials but design counts as well if you consider fold-back current limiting and crowbar circuits.

[SirNick]

To be fair, you're kidding yourself if you think any given piece of electronics can be totally safe.  In just my experience as a consumer, I've seen several reputable power supplies fail with smoke and projectiles.  While unlikely (they were designed to contain a certain amount of this), they could've started a fire.

For high-current devices (like an amplifier), it takes a beefy fuse to support the maximum rated load.  However, typical use will be well below that limit .. and as such typical users will do dumb things like plug them into undersized extension cords and power strips, and get away with it during non-fault conditions.  E.g., I had a car amp short out internally and melt the insulation off its power cables.  The upstream fuse blew, but not before the remaining cable adhered itself to my car's upholstery.  That could've easily been a fire.  It was my own fault for using the minimum rated power cable -- a mistake I won't make again.  But it only takes once.

[T3sl4co1l]

To be fair, you're kidding yourself if you think any given piece of electronics can be totally safe.  In just my experience as a consumer, I've seen several reputable power supplies fail with smoke and projectiles.  While unlikely (they were designed to contain a certain amount of this), they could've started a fire.

Once saw an industrial MeanWell (480VAC input, 24V 5A output, DIN rail mounted -- good compact size and efficiency for its ratings, and excellent price at that) go pear-shaped.  It had gotten moisture inside.  There was severe blackening around the traces near the switching transistors (obviously, some droplets were up to no good there), and the fuse...there was no trace of.  In this model, they used a 3AG size fuse, which I'm not sure if it was glass or ceramic (I hope it was ceramic!), but yeah, it got destroyed with prejudice.

The chassis (which is perforated on most sides for ventilation) did its job containing the arc flash though.

Depending on just where it failed, it could probably be better or worse, but that's the main point of safety procedures in that sort of domain (480V+ industrial): keep away from it, because it is (literally) explosive when it goes!

Tim

[ciccio]

I think it is a monumentally stupid idea.  What if the "breaker" is the first thing to fail?  What if a customer figures out how to bypass it thereby creating a larger safety issue?

If the device has an increasing risk over time of suffering catastrophic failure which could spread, then design in safety in depth.  Typically this involves metal shielding, fusible links, and fire resistant materials but design counts as well if you consider fold-back current limiting and crowbar circuits.

In my post, I said that I did not agree with my custome's idea, but I actually I do not believe that it is a "monumentally stupid idea".
I'm talking about 30 to 40 years old power amplifiers. The simple fact that they are still working (maybe with some problems, a dryed-up capacitor or two) confirms that the original design (the designer is retired, and well alive at the age of 92 years) was sound and safe and "state of the art".

My new car forces me to change oil at some intervals, and if I do not oblige,  after about 1000 km from the first signal the engine will not start.
One of my CAD programs says that the licence has expired (don't remember of a time limit, but cannot find the original papers) and does not work anymore.
I this really different from some "part" with a limited life that will break without other damages before any other part, and will require some technician to open the rack, check cables for undamaged insulation and rodent's bytes, and some unexpected work from an unknown and incompetent technician?

I know the end users: as was pointed out by SirNick some posts above, it is practically impossible to program any preventive maintenance with the "standard" customer: they simply refuse the idea.

Another example: I have a friend who was in TV service, for a BIG manufacturer. He showed me a board that was populated with 1/8 W resistors, that were overheating by design.
The standard failure was after 3 years of service. He replaced with 1/4 W parts, and the sets are still working after many years.  Was this  BAD design, or planned obsolescence?

Following my advice, my customer will write a letter to the owners of the oldest systems, and disclaim any liability for any damage. His lawyer is working on it.

Best regards

[David Hess]

My new car forces me to change oil at some intervals, and if I do not oblige,  after about 1000 km from the first signal the engine will not start.
One of my CAD programs says that the licence has expired (don't remember of a time limit, but cannot find the original papers) and does not work anymore.
I this really different from some "part" with a limited life that will break without other damages before any other part, and will require some technician to open the rack, check cables for undamaged insulation and rodent's bytes, and some unexpected work from an unknown and incompetent technician?

It is different if it was not made clear to the customer that the design life is enforced making the product a rental instead of a sale.  I am dubious of examples like your car because all too often manufacturers take advantage of what could be a genuine safety feature to extract rents.

Maybe I was a excessively harsh.  It is "unusually stupid" if the artificial restriction is in lieu of proper safe design.

Another example: I have a friend who was in TV service, for a BIG manufacturer. He showed me a board that was populated with 1/8 W resistors, that were overheating by design.
The standard failure was after 3 years of service. He replaced with 1/4 W parts, and the sets are still working after many years.  Was this  BAD design, or planned obsolescence?

They were probably just being cheap.

Occasionally I run across designs like this where the under specified part fulfills some other function.  Carbon composition resistors for instance make pretty good fusible links because they tend to fail open and a low wattage part might be selected deliberately in that case.

Sometimes it is because no other option is economically available.  Precision metal film resistors for example are not generally available with high power ratings.