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Reflow profile verification ??!!!

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#39032

Reflow profile verification ??!!! | 13 January, 2006

How would you like to have this guy evaluate your reflow profile?

It was in response to an auditor who require someone they had monitor temperature in both Fahrenheit and Celcius. What a geek

Don't put him on the spot. That is not a good thing to do to an auditor. Instead, give him a conspiratorial wink and acknowledge his observation with a remark such as "Hey, you're a pretty sharp guy to pick up on that!"

Then ask him where he learned about the elementary constituants of a thermally active physical system, where kBT is temperature expressed in terms of Boltzmann's constant, in Kelvin. And did he know that thermodynamic equilibrium is defined by a relation between the amount of heat incident on the system during an infinitesimal quasistatic transformation, and what is the variation of its time-to-entropy during the transformation?

If he nods wisely, ask him what are his feelings about the effects of the gas expansion factor when calculating the Zeroth dynamic during measurements of the thermal mass to entropy betweem multiple static objects collectively within a vacuum using Boltzmann's theory of distribution.

At this point, while he stands there and stutters with his eyes glazed over, let him know that the reasons you used only temperatures Celcius, is because after much research looking at the Carnot heat engine equivalency of a standard PWB using a dissipation factor of 10 while powered up with 100kiv/cm squared, it was apparent that with the heat conduction factor being what it is at 22 gigahertz and its effect on the overall conductance, the only apparent measurements that would work would be in the Reaumur, Rankine, Delisle, and Newton units for the needed accuracy inherent to the process, because the conversion factors from these to the terakelvin range are beyond the scope of the computational system you are using to meet the contract.

And the dweebs in IS cannot provide any more memory capability to your desktop PC.

The key here is to answer their questions precisely.

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#39045

Reflow profile verification ??!!! | 13 January, 2006

Good one! I remember at my old company, the auditors, both internal and external would go immediately to the refrigerator where we kept our glue and solder paste and then they would spend most of their time there, because they were afraid of all of the machines (and the machines and processes is where all of our ISO violations were).....they were so dumb, they'd go to something "familiar", and what's more familiar than a fridge???

I've had to do some may dumb tasks resulting from their audit findings.. I must've changed the Fridge's work instruction at least a dozen times, and then had to put both the internal and external thermometers on a calibration schedule....

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#39057

Reflow profile verification ??!!! | 13 January, 2006

What are you two ranting about?

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DannyJ

#39064

Reflow profile verification ??!!! | 13 January, 2006

Sr. Tech,

First, thank you for the great laugh!

Second, I always go for that 'deer caught in headlights look' that they get when you start asking your questions. As a caveat, I have learned to slow down when they start drooling out of one side of their mouth. This is a good indication that they are going to enter brain meltdown or be left in a vegatative state. This can be pricey, since you cannot dispose of the auditor with your dross. (Unless finely minced, of course...)

(For any auditors out there... don't take this too personal. Just take it for what it is, someone had a bad experience with an auditor, we all have. Learn from other's mistakes!)

Dan

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