So, you have some equipment for monitoring temparature sensors and 
logging their readings. And you supply some software that downloads this 
data and lets you organise and examine it on a desktop PC.

Your hardware and software are designed to talk to each other via a 
serial cable connecting the hardware to the PC running the software.

Ah, but some people want to actually, you know, have the PC in a 
different room to where the hardware is. And they'd like to not have to 
dedicate one entire PC to each logger. The answer is simple: your 
product needs to communicate over the network!

Now, you *could* redesign your hardware so it has an Ethernet port, and 
redesign your software so it understands TCP/IP. But you're not going to.

Instead, what you do is supply your customers with a little black box. 
This little black box has a serial connector at one end, and an Ethernet 
connection at the other, and it *tunnels* serial traffic over IP.

You also supply your customers with a blob of software which, when 
installed on a PC, somehow tricks the PC into thinking it has a new 
serial port. All data sent to this port is *actually* tunnelled to the 
little black box.

So, between the little black box at one end, and the custom software 
driver at the other end, the hardware and software geniunely believe 
they're still locally connected, yet actually they can be on different 
continents.

Is this a valid solution to a design problem? Or is it a cheap hack?

[Did I mention that the "software" in question appears to be designed to 
work with Windows 3.0? Does that change the answer?]

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Invisible wrote:
> Is this a valid solution to a design problem? Or is it a cheap hack?

It's a floor wax *and* a salad dressing!

Seriously, that's not at all uncommon in the world of credit card 
terminals. You would rather buy 20 $25 serial boxes than replace 20 $300 
credit card terminals when you go to a networked cash register thingie.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

On Wed, 14 May 2008 16:13:30 +0100, Invisible wrote:

> Is this a valid solution to a design problem?

Yes.  I see this occasionally with KVM switches (Avocent does this, for 
example) as a way of "extending" a connection.

Jim

Post a reply to this message

>> Is this a valid solution to a design problem?
> 
> Yes.  I see this occasionally with KVM switches (Avocent does this, for 
> example) as a way of "extending" a connection.

Heh. A KVM switch would be a *horrible* solution for this particular 
problem. I mean, tunneling arbitrary serial data over IP isn't great. 
But then, I guess serial is pretty speed limited anyway, so it shouldn't 
use too much network bandwidth...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

> It's a floor wax *and* a salad dressing!

Well... I hate salad anyway, so... ;-)

> Seriously, that's not at all uncommon in the world of credit card 
> terminals. You would rather buy 20 $25 serial boxes than replace 20 $300 
> credit card terminals when you go to a networked cash register thingie.

Subtle nit-pick, but... We're buying a brand new system, not augmenting 
an existing one. If we were augmenting an existing one, then yeah, I can 
see how just fitting a little extra hardware is clearly the 
cost-effective option. I'm not sure how that works when you're buying 
something completely brand-new, and it's already partially kludged so 
the manufacturers don't have to redesign it... What's your opinion?

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Orchid XP v8 wrote:
> the manufacturers don't have to redesign it... What's your opinion?

My opinion is that if it only works on Win 3, it's because it's 
accessing the serial hardware directly, so it's already a kludge even 
before the little black box. :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

Darren New wrote:

> My opinion is that if it only works on Win 3, it's because it's 
> accessing the serial hardware directly, so it's already a kludge even 
> before the little black box. :-)

Oh no, it *looks* like something from Win 3. It actually *works* on NT4 
[and possibly newer, I haven't tried]. ;-)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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On Wed, 14 May 2008 19:56:55 +0100, Orchid XP v8 wrote:

>>> Is this a valid solution to a design problem?
>> 
>> Yes.  I see this occasionally with KVM switches (Avocent does this, for
>> example) as a way of "extending" a connection.
> 
> Heh. A KVM switch would be a *horrible* solution for this particular
> problem. I mean, tunneling arbitrary serial data over IP isn't great.
> But then, I guess serial is pretty speed limited anyway, so it shouldn't
> use too much network bandwidth...

Well, I wasn't saying a KVM would be a solution (I don't even know the 
circumstances really), just that I've seen Avocent/Cybex switches that 
use serial-to-ethernet adapters in order to extend the range.  Range 
extenders have been around for quite a while, though - both for serial 
and parallel devices (can't remember the name of the company that did the 
parallel extenders I used years ago).

Jim

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Just get a temperature logger with a USB interface and a decent API, connect 
it to a cheap old PC, which is running some software *you* wrote to read out 
the data and send it over LAN to some server in some useful format.

That's what I do here :-)

Post a reply to this message

scott wrote:
> Just get a temperature logger with a USB interface and a decent API, 
> connect it to a cheap old PC, which is running some software *you* wrote 
> to read out the data and send it over LAN to some server in some useful 
> format.
> 
> That's what I do here :-)

Well, this is for mission-critical stuff, so we have a service contract 
and all that kind of thing, so we basically get the hardware and 
software they provide. But yeah, if support wasn't an issue, that's 
probably what I'd do...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

> Well, this is for mission-critical stuff, so we have a service contract 
> and all that kind of thing, so we basically get the hardware and software 
> they provide. But yeah, if support wasn't an issue, that's probably what 
> I'd do...

Yeh, guess you don't want to be held responsible when it breaks for 
something mission critical, better to be able to pass the responsibility on 
(even if they haven't updated their software since Win3.1!).

Still, you could encourage them to make some updates (like using USB instead 
of serial, and writing software for XP/Vista rather than Win3.1), or buy the 
system from a more up to date supplier that is less hacky.

Post a reply to this message

scott wrote:

> Yeh, guess you don't want to be held responsible when it breaks for 
> something mission critical, better to be able to pass the responsibility 
> on (even if they haven't updated their software since Win3.1!).
> 
> Still, you could encourage them to make some updates (like using USB 
> instead of serial, and writing software for XP/Vista rather than 
> Win3.1), or buy the system from a more up to date supplier that is less 
> hacky.

Well now, if you want a couple of thermometers and a data logger, 
that'll be about £20. Now if you write the words "mission critical" on 
it, suddenly the same hardware costs £12,000. Strange, that. But hey, 
it's mission critical. What are you gonna do? You simply *have* to have 
this thing, so basically you have to pay whatever they charge you. Which 
is probably _why_ they charge you so much. ;-)

I wasn't in any way involved in the purchase process, but I gather that 
we were quoted tens of thousands of pounds by various parties, and we 
eventually went with the lowest bidder. As far as I know...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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> Now if you write the words "mission critical" on it, suddenly the same 
> hardware costs £12,000. Strange, that.

Not really, I assume the hardware is of a much higher specification than 
some *really* cheap consumer version you could get for 20 quid.

> But hey, it's mission critical. What are you gonna do? You simply *have* 
> to have this thing, so basically you have to pay whatever they charge you. 
> Which is probably _why_ they charge you so much. ;-)

Usually you have the option of other suppliers, so the price should be 
pretty competitive for what you're getting. Otherwise they would go out of 
business if everyone else could sell the same product for half the price.

> I wasn't in any way involved in the purchase process, but I gather that we 
> were quoted tens of thousands of pounds by various parties, and we 
> eventually went with the lowest bidder.

If you were about to spend 10k on something, would you blindly take the 
cheapest one without even bothering to see exactly what you were getting? 
Sadly a lot of companies do exactly this, often with much larger sums of 
money...

Post a reply to this message

scott wrote:
>> Now if you write the words "mission critical" on it, suddenly the same 
>> hardware costs £12,000. Strange, that.
> 
> Not really, I assume the hardware is of a much higher specification than 
> some *really* cheap consumer version you could get for 20 quid.

Well... It measures temparatures to the nearest 0.1°C. It records them 
every 15 minutes. If they go outside a preset range, an alarm goes off. 
How much would *you* suggest such a system costs?

>> But hey, it's mission critical. What are you gonna do? You simply 
>> *have* to have this thing, so basically you have to pay whatever they 
>> charge you. Which is probably _why_ they charge you so much. ;-)
> 
> Usually you have the option of other suppliers, so the price should be 
> pretty competitive for what you're getting. Otherwise they would go out 
> of business if everyone else could sell the same product for half the 
> price.

Apparently all the suppliers we could find were charging 5 figures for 
something that will do what we want. Seems absurd to me, but... mission 
critical, gotta have one, gotta be up and running before date X...

> If you were about to spend 10k on something, would you blindly take the 
> cheapest one without even bothering to see exactly what you were 
> getting? Sadly a lot of companies do exactly this, often with much 
> larger sums of money...

Well, you'd hope so... but as I say, I wasn't really involved in the 
process. I believe the hardware was all much the same, so they went with 
the cheapest option from a supplier who could actually supply on time.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

> Well... It measures temparatures to the nearest 0.1°C. It records them 
> every 15 minutes. If they go outside a preset range, an alarm goes off. 
> How much would *you* suggest such a system costs?

Depends on far more than just the raw technical performance.

If I'm going to use it check the temperature in my greenhouse, I would 
imagine a 50 quid jobby from Maplins would do with some cheap hacked 
together Win3.1 program.  However, if I'm putting it in a manned spacecraft 
that is orbiting the moon, I would expect way higher performance, and an 
equally higher price.

BTW, the stuff we make here, we always have to put on the 1st page of the 
specification that it is not to be used in anything critical, like plane 
instruments, hospital equipment, traffic signals etc, simply because we 
don't design or test to high enough standards.  If we did, the cost would be 
astronomical, for stuff like PC monitors you don't need that level of 
reliability so you get them very cheap.

Post a reply to this message

On Thu, 15 May 2008 12:54:16 +0100, Invisible <voi### [at] devnull> wrote:

>
>Apparently all the suppliers we could find were charging 5 figures for 
>something that will do what we want. Seems absurd to me, but... mission 
>critical, gotta have one, gotta be up and running before date X...

Is the equipment and software certified? Because that adds to the
cost. 
-- 

Regards
     Stephen

Post a reply to this message

Invisible wrote:
> So, you have some equipment for monitoring temparature sensors and 
> logging their readings. And you supply some software that downloads this 
> data and lets you organise and examine it on a desktop PC.
> 
> You also supply your customers with a blob of software which, when 
> installed on a PC, somehow tricks the PC into thinking it has a new 
> serial port. All data sent to this port is *actually* tunnelled to the 
> little black box.
> 
> So, between the little black box at one end, and the custom software 
> driver at the other end, the hardware and software geniunely believe 
> they're still locally connected, yet actually they can be on different 
> continents.
> 
> Is this a valid solution to a design problem? Or is it a cheap hack?
> 
> [Did I mention that the "software" in question appears to be designed to 
> work with Windows 3.0? Does that change the answer?]
> 

If it is an existing system that needs to be made network 'aware' then 
it is a valid solution, but one that should be taken with caution.

Recently I built something that does exactly that.

I have some GPS modules that speak serial.
I built a custom serial/ethernet module.  But this one is smart - it has 
a buffer and built in web page for basic GPS info.
On the computer I run a ethernet/comm port emulator so that programs 
that expect only a comm port can work.
But one better, the serial/ethernet module allows for multiple 
connections - I can get multiple computers and applications pulling the 
same data on comm ports.

IMHO, a serial-ethernet module should be used as a last resort when 
there is no viable alternative.

If it is a mission critical application, then you are just introducing 
more points for failure.  When one of those points die, then it takes 
all that much longer to debug.


This reminds me of what would be put in at the GM-Saturn plant I worked 
in several years ago.  You kludge a bunch of stuff together until it 
works, then repeat and put 50 of them on the plant floor.  Even tho if 
one of them failed it would stop the production line.  I ran into some 
strange setups - parallel to serial to ethernet to serial to com 
port....  and in one case it took 3 days to figure out what piece failed.


Best of luck!

LAter... Tom

Post a reply to this message

scott wrote:
>> Well... It measures temparatures to the nearest 0.1°C. It records them 
>> every 15 minutes. If they go outside a preset range, an alarm goes 
>> off. How much would *you* suggest such a system costs?
> 
> Depends on far more than just the raw technical performance.
> 
> If I'm going to use it check the temperature in my greenhouse, I would 
> imagine a 50 quid jobby from Maplins would do with some cheap hacked 
> together Win3.1 program.  However, if I'm putting it in a manned 
> spacecraft that is orbiting the moon, I would expect way higher 
> performance, and an equally higher price.

Well, we'd like to check that the blood samples we're storing actually 
*stay* at -80°C. And if they start to warm up, somebody needs to know 
about this fact, urgently.

I'm guessing a temparature sensor that actually *works* at temparatures 
that low is going to cost a tad more than your average room thermometer, 
but beyond that I don't see why it would need to cost more. It seems the 
only reason for the higher price is that this is a critical device, so 
the suppliers know they can charge the Earth and we will pay it. We have to.

> BTW, the stuff we make here, we always have to put on the 1st page of 
> the specification that it is not to be used in anything critical, like 
> plane instruments, hospital equipment, traffic signals etc, simply 
> because we don't design or test to high enough standards.  If we did, 
> the cost would be astronomical, for stuff like PC monitors you don't 
> need that level of reliability so you get them very cheap.

The mass spectrometers we have here all say "for research and 
development only; not for diagnostic procedures" on them. I can't 
imagine why - it's a mass spectrometer! Either it measures masses 
reliably, or it doesn't. If it does, you can use it for anything you 
like. If it doesn't, it's a worthless piece of equipment. So... why the 
sticker?!

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Stephen wrote:

> Is the equipment and software certified? Because that adds to the
> cost. 

Not by the supplier, I don't *think*. Certainly *we* will be regularly 
checking it against an ISO standards-certified reference instrument 
[which really *is* insanely expensive]. But I don't *think* the 
suppliers actually provide any such guarantees - I'm not sure...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

> Well, we'd like to check that the blood samples we're storing actually 
> *stay* at -80°C. And if they start to warm up, somebody needs to know 
> about this fact, urgently.

What are the consequences if the temperature goes above -80°C but nobody is 
informed?  Would you trust a 20 quid meter from Maplin then?

> I'm guessing a temparature sensor that actually *works* at temparatures 
> that low is going to cost a tad more than your average room thermometer,

Not really, thermocouples are cheap (like a fiver) and measure down to 
below -100 degrees.

> but beyond that I don't see why it would need to cost more. It seems the 
> only reason for the higher price is that this is a critical device, so the 
> suppliers know they can charge the Earth and we will pay it. We have to.

Or the fact that there is a much lower chance it will break or mal-function. 
A simple example I can think of is that the connector where the thermal 
probe plugs in mal-functions somehow so that the electronics thinks that the 
temperature is -90 when really it is only -70.  Or some solder joint on the 
circuit board wasn't made completely correctly and messes up some other 
reading in an undetectable way once the temperature and humidity get to a 
certain value.  There are all sorts of failure mechanisms that needs to be 
checked and fixed somehow, and that costs lots of money.

> The mass spectrometers we have here all say "for research and development 
> only; not for diagnostic procedures" on them. I can't imagine why - it's a 
> mass spectrometer! Either it measures masses reliably, or it doesn't. If 
> it does, you can use it for anything you like. If it doesn't, it's a 
> worthless piece of equipment. So... why the sticker?!

Because they don't guarantee it will work reliably the whole time.  For them 
to guarantee that, they would need to do lots of expensive testing on every 
unit, probably design in lots of redundant systems, use more expensive 
components that have longer lifetimes, use better assembly methods etc.

Post a reply to this message

>> Well, we'd like to check that the blood samples we're storing actually 
>> *stay* at -80°C. And if they start to warm up, somebody needs to know 
>> about this fact, urgently.
> 
> What are the consequences if the temperature goes above -80°C but nobody 
> is informed?  Would you trust a 20 quid meter from Maplin then?

My point exactly - it seems to have nothing to do with how reliable the 
device is, only the subjective feeling it gives you in your head knowing 
that "I paid lots of money for this, therefore it must be really 
reliable". Which isn't terribly scientific...

>> I'm guessing a temparature sensor that actually *works* at 
>> temparatures that low is going to cost a tad more than your average 
>> room thermometer,
> 
> Not really, thermocouples are cheap (like a fiver) and measure down to 
> below -100 degrees.

Well, maybe you have to be slightly more careful that, e.g., the 
insulator on the wire doesn't become as brittle as glass when it gets 
too cold or something.

I remember seeing how a metal cylinder costs about £20, but a metal 
cylinder that you can put liquid nitrogen into costs £500. Because 
somebody has to check it won't break or something when it gets that damn 
cold.

>> It seems 
>> the only reason for the higher price is that this is a critical 
>> device, so the suppliers know they can charge the Earth and we will 
>> pay it. We have to.
> 
> Or the fact that there is a much lower chance it will break or 
> mal-function.

Why? Do they actually *do* something different with it? Does the 
hardware itself have any actual physical differences to a cheap model? 
As far as I can tell, they took a device that normally costs £50, added 
a several thousand percent markup, and started marketting it at a 
different market segment.

On the other hand, I remember researching printers one time. I ended up 
looking at two printers. Both Hewlett Packard. Both print at 1200dpi. 
Both have built-in network support. Both do duplex printing. Etc. But 
one printer was about 10x the price of the other. Why?

The answer is a little number hidden at the bottom of the page 
somewhere: "duty cycle". One printer said 1,000 pages/month, the other 
said 100,000 pages/month. And you know what? We ended up buying both 
printers, and one is still working to this day, the other one we 
eventually threw away because it just kept breaking so often.

In this case, it seems paying 10x the price does, in fact, get you a 
device which is *physically different*. I don't know if they use thicker 
plastic for the drive gears or what, but the more expensive printer was 
far more reliable. The cheap one is basically designed to sit in your 
house. [Actually, I have one at home. It works just fine. But then, I 
hardly ever print anything!] Put that printer in a busy office and it 
just can't cope.

>> The mass spectrometers we have here all say "for research and 
>> development only; not for diagnostic procedures" on them. I can't 
>> imagine why - it's a mass spectrometer! Either it measures masses 
>> reliably, or it doesn't. If it does, you can use it for anything you 
>> like. If it doesn't, it's a worthless piece of equipment. So... why 
>> the sticker?!
> 
> Because they don't guarantee it will work reliably the whole time.  For 
> them to guarantee that, they would need to do lots of expensive testing 
> on every unit, probably design in lots of redundant systems, use more 
> expensive components that have longer lifetimes, use better assembly 
> methods etc.

Well, you're the engineer. But I wonder - if a mass spectrometer that 
you can't use for diagnostic procedures costs £250,000... what the HELL 
does one you *can* use for diagnostic procedures cost?! o_O

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

On Thu, 15 May 2008 15:18:18 +0200, "scott" <sco### [at] scottcom> wrote:

>
>Or the fact that there is a much lower chance it will break or mal-function. 
>A simple example I can think of is that the connector where the thermal 
>probe plugs in mal-functions somehow so that the electronics thinks that the 
>temperature is -90 when really it is only -70.  Or some solder joint on the 
>circuit board wasn't made completely correctly and messes up some other 
>reading in an undetectable way once the temperature and humidity get to a 
>certain value.  There are all sorts of failure mechanisms that needs to be 
>checked and fixed somehow, and that costs lots of money.

You need to ensure that the cold joint (or in this case the hot joint)
is compensated properly for changes in the ambient temperature. 
For medical/critical equipment you need certification to ensure
compliance with the laws of the country. And not just UK laws it
should comply with the laws of the registered country. In your case I
imagine that is the USA.
-- 

Regards
     Stephen

Post a reply to this message

On Thu, 15 May 2008 13:52:37 +0100, Invisible <voi### [at] devnull> wrote:

>Stephen wrote:
>
>> Is the equipment and software certified? Because that adds to the
>> cost. 
>
>Not by the supplier, I don't *think*. Certainly *we* will be regularly 
>checking it against an ISO standards-certified reference instrument 
>[which really *is* insanely expensive]. But I don't *think* the 
>suppliers actually provide any such guarantees - I'm not sure...

Buy the cheapest and that is what you get. And is your secondary
calibrator regularly checked against a primary calibrator?
-- 

Regards
     Stephen

Post a reply to this message

> My point exactly - it seems to have nothing to do with how reliable the 
> device is, only the subjective feeling it gives you in your head knowing 
> that "I paid lots of money for this, therefore it must be really 
> reliable". Which isn't terribly scientific...

Surely you check out the specification before buying something?  It will 
include details about *how* reliable it is, with real numbers, and under 
what conditions it has been tested in.  Something you buy from Maplins won't 
have this.

> I remember seeing how a metal cylinder costs about £20, but a metal 
> cylinder that you can put liquid nitrogen into costs £500. Because 
> somebody has to check it won't break or something when it gets that damn 
> cold.

Exactly - someone has to check - and that costs money.

> Why? Do they actually *do* something different with it?

Yes, it is designed to be more reliable, and they test it to prove this so 
they can write it in the specification of the device.

> Does the hardware itself have any actual physical differences to a cheap 
> model?

Probably, if you're lucky you could get a *really* reliable one from Maplin 
that lasted for 1000 years without any problems.  *Lucky* being the key word 
here, try explaining to someone's family that they died because some monitor 
failed, you can't say "we were unlucky".

> As far as I can tell, they took a device that normally costs £50, added a 
> several thousand percent markup, and started marketting it at a different 
> market segment.

And put in place processes for guaranteeing the reliability of the product, 
at least testing each one and working with their suppliers to ensure that 
correct procedures are followed to avoid any unreliabilities.  You see those 
news stories about paint from China causing problems?  Without controlling 
your suppliers properly stuff like that happens - and if you are supplying 
something you claim to be suitable for critical processes, you are in deep 
trouble if you allow your suppliers or your own processes to screw up.

> The answer is a little number hidden at the bottom of the page somewhere: 
> "duty cycle". One printer said 1,000 pages/month, the other said 100,000 
> pages/month. And you know what? We ended up buying both printers, and one 
> is still working to this day, the other one we eventually threw away 
> because it just kept breaking so often.

Exactly.

> In this case, it seems paying 10x the price does, in fact, get you a 
> device which is *physically different*. I don't know if they use thicker 
> plastic for the drive gears or what, but the more expensive printer was 
> far more reliable. The cheap one is basically designed to sit in your 
> house. [Actually, I have one at home. It works just fine. But then, I 
> hardly ever print anything!] Put that printer in a busy office and it just 
> can't cope.

The same way that buying a 20 quid power drill from B&Q is fine if you only 
use it once a month to drill a few holes.  But if you are a builder and you 
use it 20 times a day, it's going to break after a week.  Which is why you 
invest in a way more expensive model.  OK so if you bought the cheap one it 
*might* last for several months, but it's not worth the risk if you really 
need your drill to work every day.

> Well, you're the engineer. But I wonder - if a mass spectrometer that you 
> can't use for diagnostic procedures costs £250,000... what the HELL does 
> one you *can* use for diagnostic procedures cost?! o_O

Medical equipment is extremely expensive, precisely because there is so much 
at risk when things go wrong.  The companies that make this stuff need to do 
a huge amount of testing and robust design, way above what most other 
industries require.  It all costs money.

Post a reply to this message

And lo on Thu, 15 May 2008 14:32:47 +0100, Invisible <voi### [at] devnull> did  
spake, saying:

Heh I love it when you get ranty about the price of mission-critical stuff.

Here's a story I was told I forget the exact measurements and prices but  
still -

A women approaches a company that make bespoke wooden doors for a new  
front door. She can't buy an off-the-rack for £100 because they're two  
inches too narrow, they quote her a price of £250. She blows her top  
shouting "You're charging me £150 for those two extra inches" and storms  
off never to return.

The moral, of course, is that she wasn't be charged an extra £150 she was  
being charged £250 to have workmen create for her a uniquely sized door  
 from scratch.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

Post a reply to this message

Invisible wrote:
> but beyond that I don't see why it would need to cost more. 

In the US, I'd say it's because if the device fails and all your blood 
samples warm up and you lose $1M of revenue, you could reasonably expect 
to sue the company that made the device to get your money back.

It's called "incidental damages" here.

If that's what you're paying for, then that's a big part of the price 
difference. If the company doesn't warrant that the device will actually 
work, then I couldn't say. Around here, a $20 thermometer is going to 
have a warranty that says "If it breaks, you might be able to get your 
$20 back, but that's about it."

> If it doesn't, it's a worthless piece of equipment. So... why the 
> sticker?!

Liability control. If you can't tell when it's broken, and you overdose 
someone because your mass spectrometer misread how much drug was in the 
solution, it's much more expensive than if you (say) ruin an 
experimental car engine by putting the wrong mix of fuel in it.

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

Invisible wrote:
> 
> Well... It measures temparatures to the nearest 0.1°C. It records them 
> every 15 minutes. If they go outside a preset range, an alarm goes off. 
> How much would *you* suggest such a system costs?

A freaking *lot* if it's calibrated so it can for sure measure up to 
0,1C and not just show that way and the service contract includes yearly 
(oslt) re-calibrations.

> Apparently all the suppliers we could find were charging 5 figures for 
> something that will do what we want. Seems absurd to me, but... mission 
> critical, gotta have one, gotta be up and running before date X...

Mission critical: you take 5 UPS's, 5 PC's, 5 sensors and wire them up 
separately. If all five from even the cheapest hardware break down 
simultaneously enough, you're having the worst luck of the world 
already. OTOH, then you won't have A) service contract, B) scheduled 
re-calibrations, C) calibration at the first place.

> Well, you'd hope so... but as I say, I wasn't really involved in the 
> process. I believe the hardware was all much the same, so they went with 
> the cheapest option from a supplier who could actually supply on time.

You weren't involved -> it's not your call -> you shouldn't stress about it.


-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid

Post a reply to this message

>> I remember seeing how a metal cylinder costs about £20, but a metal 
>> cylinder that you can put liquid nitrogen into costs £500. Because 
>> somebody has to check it won't break or something when it gets that 
>> damn cold.
> 
> Exactly - someone has to check - and that costs money.

Well that at least makes sense. You're paying money *for* something.

>> Why? Do they actually *do* something different with it?
> 
> Yes, it is designed to be more reliable, and they test it to prove this 
> so they can write it in the specification of the device.

This somewhat implies that normal stuff is designed to be UNreliable. ;-)

>> Does the hardware itself have any actual physical differences to a 
>> cheap model?
> 
> Probably, if you're lucky you could get a *really* reliable one from 
> Maplin that lasted for 1000 years without any problems.  *Lucky* being 
> the key word here, try explaining to someone's family that they died 
> because some monitor failed, you can't say "we were unlucky".

I'm just wondering whether they actually did anything different at all 
for the extra money, that's all.

It's like when you order stuff online. You can pay £2, and they tell you 
it'll take up to 15 days to arrive. But actually it arrives within 12 
hours. Or you can pay £15 to have it guaranteed to arrive within 12 
hours. And it still arrives within 12 hours. Do they actually do 
anything different? Or is it just a tax on stupidity?

On the other hand, consider the printers example. Clearly something *is* 
actually different, because the printers really do perform differently. 
So in this case, you *are* getting something for your money.

I'm not sure which category this temparature monitor falls into.

>> Well, you're the engineer. But I wonder - if a mass spectrometer that 
>> you can't use for diagnostic procedures costs £250,000... what the 
>> HELL does one you *can* use for diagnostic procedures cost?! o_O
> 
> Medical equipment is extremely expensive, precisely because there is so 
> much at risk when things go wrong.  The companies that make this stuff 
> need to do a huge amount of testing and robust design, way above what 
> most other industries require.  It all costs money.

Heh. And I thought a device that costs more than my house (!!) was 
already expensive. ;-)

[Seriously - WTF does a mass spectrometer even have in it? It's just an 
empty tube, some vacuum pumps, an electrode and some magnets. So is my 
TV! Well, apart from the vacuum pumps anyway... And yet, my TV doesn't 
cost more than a small housing estate. Wuh??]

BTW, wasn't there some famous disaster with a device for radiotherapy 
that accidentally overdosed a few people?

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Eero Ahonen wrote:

> You weren't involved -> it's not your call -> you shouldn't stress about 
> it.

Oh, hey, I'm not *stressing* about this! I couldn't care less. ;-) I'm 
merely curios about the design of it...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

On Thu, 15 May 2008 22:10:07 +0100, Orchid XP v8 <voi### [at] devnull>
wrote:

>
>>> Why? Do they actually *do* something different with it?
>> 
>> Yes, it is designed to be more reliable, and they test it to prove this 
>> so they can write it in the specification of the device.
>
>This somewhat implies that normal stuff is designed to be UNreliable. ;-)

He said "more" reliable. Have you heard of tolerances?
-- 

Regards
     Stephen

Post a reply to this message

> This somewhat implies that normal stuff is designed to be UNreliable. ;-)

Of course it is, everything has a designed lifetime, even the on/off button 
on the front of your computer.  Why put a switch that is guaranteed to have 
a minimum of 1 million operations over -40 to 100°C on an ordinary PC?  Some 
situations call for this sort of reliability though, and you pay for it.

The tiny plugs/sockets that are used inside laptops and mobile phones etc 
often have a designed lifetime of just *ONE* operation!  It means everything 
can be made much smaller and thinner and hence cheaper, but of course you 
wouldn't use one of these if you were expecting to actually use the plug 
regularly.

> I'm just wondering whether they actually did anything different at all for 
> the extra money, that's all.

Well they must have done if they are guaranteeing it for critical use.  If 
they didn't they risk being in a lot of trouble when things do fail (or 
maybe there is even some law that is relevant, I don't know).  Are they ISO 
9000 accredited?

> It's like when you order stuff online. You can pay £2, and they tell you 
> it'll take up to 15 days to arrive. But actually it arrives within 12 
> hours. Or you can pay £15 to have it guaranteed to arrive within 12 hours. 
> And it still arrives within 12 hours. Do they actually do anything 
> different? Or is it just a tax on stupidity?

Again, paying extra is guaranteeing next day delivery, it means more work 
for them, more work for the delivery company, and hence is more expensive. 
Of course if they happen to have space on the truck they'll probably fill it 
up with non-next-day orders - but it's not guaranteed.  If the truck is full 
and they still have next day orders to ship, they get another truck over, 
which isn't free.

> [Seriously - WTF does a mass spectrometer even have in it? It's just an 
> empty tube, some vacuum pumps, an electrode and some magnets. So is my TV! 
> Well, apart from the vacuum pumps anyway... And yet, my TV doesn't cost 
> more than a small housing estate. Wuh??]

How many TVs do you think have been made in total?  How many mass 
spectrometers?

What do you think is the tolerance on TVs?  Would you care if the green on 
the UK weather map looks a slightly different shade to your neighbour?

Post a reply to this message

> A women approaches a company that make bespoke wooden doors for a new 
> front door. She can't buy an off-the-rack for £100 because they're two 
> inches too narrow, they quote her a price of £250. She blows her top 
> shouting "You're charging me £150 for those two extra inches" and storms 
> off never to return.
>
> The moral, of course, is that she wasn't be charged an extra £150 she was 
> being charged £250 to have workmen create for her a uniquely sized door 
> from scratch.

Hehe, or a more extreme example would be wandering into PC World and saying 
you want a 1921x1200 resolution monitor custom made.  Ermm, that will be 
several million pounds sir.

Post a reply to this message

> The tiny plugs/sockets that are used inside laptops and mobile phones 
> etc often have a designed lifetime of just *ONE* operation!  It means 
> everything can be made much smaller and thinner and hence cheaper, but 
> of course you wouldn't use one of these if you were expecting to 
> actually use the plug regularly.

I think my grandparents have used up the one connection on their mobile 
phone. It is simply no longer possible to get a reliable USB connection. 
You have to try about 8 or 9 times. The connector is just useless...

>> I'm just wondering whether they actually did anything different at all 
>> for the extra money, that's all.
> 
> Well they must have done if they are guaranteeing it for critical use.  
> If they didn't they risk being in a lot of trouble when things do fail 
> (or maybe there is even some law that is relevant, I don't know).  Are 
> they ISO 9000 accredited?

That's the thing. I don't *think* the company in question is actually 
guaranteeing it will work. They're just charging lots of money. We're 
the ones who do all the calibration checking and so forth.

>> [Seriously - WTF does a mass spectrometer even have in it? It's just 
>> an empty tube, some vacuum pumps, an electrode and some magnets. So is 
>> my TV! Well, apart from the vacuum pumps anyway... And yet, my TV 
>> doesn't cost more than a small housing estate. Wuh??]
> 
> How many TVs do you think have been made in total?  How many mass 
> spectrometers?

If you were asking "particle accelerators", it would be a different 
story. ;-) Mass spectrometers are fairly rare, but not all that rare. 
Although obviously rarer than TVs.

> What do you think is the tolerance on TVs?  Would you care if the green 
> on the UK weather map looks a slightly different shade to your neighbour?

That might have something to do with it...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Stephen wrote:

> He said "more" reliable. Have you heard of tolerances?

Yeah.

Did you know 10% resistors show a curios bimodel distribution?

Wanna guess where the 5% resistors come from? ;-)

[And they charge you more for that stuff...]

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

On Fri, 16 May 2008 09:19:07 +0100, Invisible <voi### [at] devnull> wrote:

>Stephen wrote:
>
>> He said "more" reliable. Have you heard of tolerances?
>
>Yeah.
>
>Did you know 10% resistors show a curios bimodel distribution?
>
>Wanna guess where the 5% resistors come from? ;-)
>
>[And they charge you more for that stuff...]

When I worked in the semiconductor industry (CMOS chips) the sorting
was done by individual sampling after the ICs were encapsulated.
Resistors and caps were by materials used in manufacturing. But that
was when the Ark was new :)
-- 

Regards
     Stephen

Post a reply to this message

Orchid XP v8 wrote:
> This somewhat implies that normal stuff is designed to be UNreliable. ;-)

Kind of, but not exactly.  It might be reliable, it might not be. 
Really it all comes down to luck - which, in the end, makes it unreliable :)

But it's not like a bunch of guys in suits sat down and said, "Now we 
need to design a version that's going to fail really soon."

> I'm just wondering whether they actually did anything different at all 
> for the extra money, that's all.

Yeah, they guaranteed that it won't fail within certain tolerances. 
Those tolerances are *much* stricter than for the cheap version.

> It's like when you order stuff online. You can pay £2, and they tell you 
> it'll take up to 15 days to arrive. But actually it arrives within 12 
> hours. Or you can pay £15 to have it guaranteed to arrive within 12 
> hours. And it still arrives within 12 hours. Do they actually do 
> anything different? Or is it just a tax on stupidity?

It's a guarantee.  Sure, you order something online and you could get it 
in 12 hours.  Or, you could get it in 2 weeks.  I've had both occur.

When you pay extra for shipping, you're paying for a guarantee that it 
will arrive within a certain timeframe.  If you're ordering a gift for 
someone's birthday, for instance, and their birthday is 3 days from now, 
do you want to gamble that the gift won't arrive on time?  Or do you 
want to know *for a fact* that it will arrive within 3 days?

> On the other hand, consider the printers example. Clearly something *is* 
> actually different, because the printers really do perform differently. 
> So in this case, you *are* getting something for your money.

As trite as the old saying is, "You get what you pay for".  A lot of the 
time, people decide that the quality really is worth the extra money 
(like your printer).  The trick is knowing when to pay for quality, and 
when to go cheap.

...Chambers

Post a reply to this message

>> I'm just wondering whether they actually did anything different at all 
>> for the extra money, that's all.
> 
> Yeah, they guaranteed that it won't fail within certain tolerances. 
> Those tolerances are *much* stricter than for the cheap version.

Well, certainly for resistors, they have a machine that just churns out 
resistors. They vary all over the place. The ones that are more than 10% 
wrong get thrown away [or perhaps recycled, IDK]. The ones that are 
within 10% of the correct value get sold cheap. And the ones that are 
within 5% of the correct value get sold expensive. But it all comes out 
of the same machine, and costs the same to produce. [Although I guess 
the 5% ones are rarer, assuming a normal distribution...]

>> It's like when you order stuff online. You can pay £2, and they tell 
>> you it'll take up to 15 days to arrive. But actually it arrives within 
>> 12 hours. Or you can pay £15 to have it guaranteed to arrive within 12 
>> hours. And it still arrives within 12 hours. Do they actually do 
>> anything different? Or is it just a tax on stupidity?
> 
> It's a guarantee.  Sure, you order something online and you could get it 
> in 12 hours.  Or, you could get it in 2 weeks.  I've had both occur.

It's like when I paid extra to have my package from Zazzle arrive fast. 
The ones I didn't pay extra for arrived within 6 days. The ones I paid 
extra for never arrived at all. In the end, I had to drive to the depot 
and get them my ****ing self! >:-[ NOT AMUSED!

[And then they tried to invoice me for unpaid VAT. I never did pay them 
that back...]

> When you pay extra for shipping, you're paying for a guarantee that it 
> will arrive within a certain timeframe.  If you're ordering a gift for 
> someone's birthday, for instance, and their birthday is 3 days from now, 
> do you want to gamble that the gift won't arrive on time?  Or do you 
> want to know *for a fact* that it will arrive within 3 days?

If only it was a *fact*. It's not like you can demand your money back 
when the item still turns up 3 weeks late...

> As trite as the old saying is, "You get what you pay for".  A lot of the 
> time, people decide that the quality really is worth the extra money 
> (like your printer).  The trick is knowing when to pay for quality, and 
> when to go cheap.

For something like a printer, which actually wears out, it can be worth 
paying more. For something that passively measures a temparature and has 
almost no possible way of malfunctioning... well, I know what I'd do. ;-)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Orchid XP v8 wrote:
> 
> Oh, hey, I'm not *stressing* about this! I couldn't care less. ;-) I'm 
> merely curios about the design of it...
> 

That's the way, keep up the good work ;).

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid

Post a reply to this message

scott wrote:
> on the UK weather map looks a slightly different shade to your neighbour?

NTSC - Never The Same Color!

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

Chambers wrote:
> But it's not like a bunch of guys in suits sat down and said, "Now we 
> need to design a version that's going to fail really soon."

You sure?  How many devices have you had that failed within days of the 
warranty expiring? ;-)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

>> But it's not like a bunch of guys in suits sat down and said, "Now we 
>> need to design a version that's going to fail really soon."
> 
> You sure?  How many devices have you had that failed within days of the 
> warranty expiring? ;-)

You know how traffic lights always turn red just as you get to them? 
Well, one day I decided to ignore them when that happens. But each time 
I arrive at a set of traffic lights just as they turn green, I'm all 
like, "woo! I got the green!"

Now almost every single set of traffic lights I come to turn green 
immediately. Seriously, you should try it!

The Jedi were right - your focus determins your reality. :-D

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Orchid XP v8 wrote:
> Now almost every single set of traffic lights I come to turn green 
> immediately. Seriously, you should try it!

Heh. I think I shall. :-)

-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

Post a reply to this message

Invisible wrote:
>>> I'm just wondering whether they actually did anything different at 
>>> all for the extra money, that's all.
>>
>> Yeah, they guaranteed that it won't fail within certain tolerances. 
>> Those tolerances are *much* stricter than for the cheap version.
> 
> Well, certainly for resistors, they have a machine that just churns out 
> resistors. They vary all over the place. The ones that are more than 10% 
> wrong get thrown away [or perhaps recycled, IDK]. The ones that are 
> within 10% of the correct value get sold cheap. And the ones that are 
> within 5% of the correct value get sold expensive. But it all comes out 
> of the same machine, and costs the same to produce. [Although I guess 
> the 5% ones are rarer, assuming a normal distribution...]

Of course they're rarer.  If they weren't, some other company would 
charge a lower price for them.

>> When you pay extra for shipping, you're paying for a guarantee that it 
>> will arrive within a certain timeframe.  If you're ordering a gift for 
>> someone's birthday, for instance, and their birthday is 3 days from 
>> now, do you want to gamble that the gift won't arrive on time?  Or do 
>> you want to know *for a fact* that it will arrive within 3 days?
> 
> If only it was a *fact*. It's not like you can demand your money back 
> when the item still turns up 3 weeks late...

Actually, you can.  At least for the shipping.

...Chambers

Post a reply to this message

Darren New wrote:
> Chambers wrote:
>> But it's not like a bunch of guys in suits sat down and said, "Now we 
>> need to design a version that's going to fail really soon."
> 
> You sure?  How many devices have you had that failed within days of the 
> warranty expiring? ;-)
> 

None, actually.  But that's probably a fluke :)

I bet what really happens is more along the lines of, "OK, we're at the 
point where it will outlast the warranty, we can stop spending money 
improving it now."

...Chambers

Post a reply to this message

On Fri, 16 May 2008 15:51:04 +0100, Invisible <voi### [at] devnull> wrote:

>

> For something that passively measures a temparature and has 
>almost no possible way of malfunctioning... well, I know what I'd do. ;-)

Sorry but you are wrong, there. Electronic components can fail under
normal usage also electronic circuits can  drift and need recalibrated
from time to time. A temperature measuring device that has a range of
-100 ºC to +100 ºC to an accuracy of 0.1 ºC has a tolerance of 0.05.
That is very accurate. 
-- 

Regards
     Stephen

Post a reply to this message

> almost no possible way of malfunctioning...

Famous last words...

Seriously, how much would *you* be willing to bet that a temperature 
measurement system from Maplin doesn't fail during 5 years use?  $1, $100, 
$100000 ?  This is exactly what bet companies have to make, and if the bet 
is millions of dollars, you don't get a $50 meter from Maplin.

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