As many of you know I have very little good to say about the modern fluke corp and the quality of their product lines so here one more for you all to ponder on relating to their present quality control.

See if you can find it...

http://www.fluke.com/fluke/uses/com...rticlecategories/electrical/leakagebasics.htm

 

yeh. 20mA vs 20μA.

 

This is embarrassing:

"For example, taking a measurement on a 240 V ac circuit with all loads disconnected might result in a value of. 0.02 A (20 mA) leakage. This value represents an insulation impedance of:

240 V / (20 x 10-6) = 12 MΩ. (Ohms Law R=V/I)"

 

And the anticipated typical powered down insulation test resistance of "50 MW or more". WBahn would have a field day with this!

 

Gee, let's see what would have happened had they just tracked their units instead of tacking them onto the end:

\(
\frac{240 V}{20mA \cdot \(M \cdot 10^{-6} \)} = 12 \times 10^6 \frac{1}{Mm}\frac{V}{A}\Omega = 12 k\Omega
\)

But, of course, tracking units is to much of a bother and clearly it adds no value, so why bother? We know what units we want the answer to have, so let's just tack them on the end to save time. Who cares?

And then, what's the point of asking if a an answer makes sense? Just wasted time. So what if we end up with a resistance measured in megawatts. Who cares?

Sheesh!

NOTE: The way I would have written this, if I wanted to be ultra explicit, would have been

\(
\frac{240 V}{20mA} \cdot \frac{1 \Omega}{(1 \; V/A)} \cdot \(m\cdot k\) = 12 k\Omega
\)

 

So what if we end up with a resistance measured in megawatts. Who cares?

Could've been worse... could've been resistance measured in furlongs...

 

Gee, let's see what would have happened had they just tracked their units instead of tacking them onto the end:
Sheesh!

I am not exactly sure when it was that I learned to "just solve the units." It was grade school for sure. I was extremely fortunate in having a few very good teachers. I also had many more bad ones (SoCal, 1950's). That is one of the most a valuable lessons I have tried to teach ever since. It frustrates me to see students omit the units as if they are a vestigial appendage like our tails.

John

 

As many of you know I have very little good to say about the modern fluke corp and the quality of their product lines so here one more for you all to ponder on relating to their present quality control.

Gee, let's see what would have happened had they just tracked their units instead of tacking them onto the end:

\(
\frac{240 V}{20mA \cdot \(M \cdot 10^{-6} \)} = 12 \times 10^6 \frac{1}{Mm}\frac{V}{A}\Omega = 12 k\Omega
\)

But, of course, tracking units is to much of a bother and clearly it adds no value, so why bother? We know what units we want the answer to have, so let's just tack them on the end to save time. Who cares?

And then, what's the point of asking if a an answer makes sense? Just wasted time. So what if we end up with a resistance measured in megawatts. Who cares?

Sheesh!

I am not so sure it was a complete failure vs a typesetting (font selection) failure.

Note that some graphic artist could have selected the whole paragraph and changed font. Suddenly the carefully formatted /Omega using symbol font and a "W" keystroke, and the /micron using symbol font and a "m" keystroke are suddenly changed from mega ohms to megawatts and micro amps to milliamps

From my point of view, you can blame the people who developed the Fluke marketing brochure but not the engineers' who wrote it. Especially if any font/formatting changes were made between the time it was proofread and converted to PDF. Note that big companies have various "corporate identity" standards. If the corporate preferred font was changed, some bozo may have reformatted a fleet of documents and republished them on the web.

I will consider it a minor quality issue, not not close to "EPIC"


----------

 

A typeset error making MΩ appear as MW is quite likely. But I doubt a typesetting error resulted in the appearance of 10^-6 instead of 10^-3. That's a sloppy units error that should have been caught and almost certainly would have been caught if the default mindset was to religiously and properly track units.

 

I am not so sure it was a complete failure vs a typesetting (font selection) failure....I will consider it a minor quality issue, not not close to "EPIC"

In the case of the statement:
"...result in a value of. 0.02 A (20 mA) leakage. This value represents an insulation impedance of:
240 V / (20 x 10-6) = 12 MΩ. (Ohms Law R=V/I)"

The author's translating 20 mA as 20 x 10-6 Amps ... that's not a typo nor a typesetting ...
as for this issue being EPIC or not, well like I always tell my son: "I've told you a MILLION times to never exaggerate..." ha ha ha...

I read somewhere that online businesses lose millions every year due to typos, grammar or orthographical errors... customers tend to lose their confidence and refrain from doing business with them...

 

Let he who is without typos cast the first stone.

 

λιθος (Greek: lithos [stone])

Moderator edit: As this is an English only site, I have chosen to make fun of your post.

Bill

 

I read somewhere that online businesses lose millions every year due to typos, grammar or orthographical errors... customers tend to lose their confidence and refrain from doing business with them...

Well I am considering it epic simply because of the former standards of accuracy and precision that fluke formerly stood for and built their reputation and following on up to about 30 or so years ago. That said I have had enough bad experience with flukes products now to feel full well justified that this slip up is a very accurate indication of their overall quality control in every aspect of their products.

The thing is this is not a printed and bound physical text mistake. It's a damn web page that should be easy for someone to go in and edit. What gets me is how long has this obvious error, and who knows how many more like it, have been in plain view on their web site for their engineering staff to have read and brought to someone attention by now yet clearly have not?

Don't their own tech staff ever read their own companies web pages and what not and if they do how exactly does something like this get by them when the printed text gives the exact formula in the same paragraph?

 

Don't their own tech staff ever read their own companies web pages and what not and if they do how exactly does something like this get by them when the printed text gives the exact formula in the same paragraph?

You're right... a prestigious, multi-million world class company should know better...

 

The problem is one more symptom of the division of labor that occurs as a company grows to successful size.

In a small firm, the blurbs and web content are written by an engineer who handles the marketing and maintains the web content in his "spare" time. I've had that role and it's thankless. It's a lot of work to get it all right, and then to keep it fresh and current. I never had time to do it as well as I wanted, just making it "not wrong" was about the best I could do while also attending to my real job. But usually it was "not wrong".

Then a company grows and, yippee, we have people that write marketing copy and other people that manage the website and other people everywhere, it seems. Well guess what, those people were not hired for their engineering prowess and can barely pronounce the words. They write all sorts of goofy stuff and apply style manuals and this year's layout design guidelines. If a technical expert is consulted for a review, it's a nuisance above and beyond their normal duties. So it doesn't get the effort level that is required. Never mind that the writer may be on another continent, barely speak the tech person's language, and maybe they don't really trust each other because they were once competitors or whatever. Point is, communication and shared effort is hard to bring together. Things slide.

If it were not for economies of scale to offset the costs of bureaucracy, there would be no large companies. They could never afford the wheel-spinning and politics that are inevitable in large organizations.

 

Recent experience with the Thermalloy website confirms this. Within 3 minutes of leaving a comment, they phoned me! I told them, "Less is more". Engineers don't care how, "stylish" your extrusions are, they only care about the numbers. The webpage looks like somebody's daughter just graduated with her degree in art.

 

I am not so sure it was a complete failure vs a typesetting (font selection) failure.[

More likely a failure to apply due diligence by the writer and "proof" reader.

 

If it were not for economies of scale to offset the costs of bureaucracy, there would be no large companies. They could never afford the wheel-spinning and politics that are inevitable in large organizations.

They lose money on everything they sell, but they make it up through volume...

 

They lose money on everything they sell, but they make it up through volume...

Been there, done that. We lived on the "pull through" business that was profitable.

John