Parts values on schematic question

Reinhardt Behm wrote in news:q46f6h$ups$ snipped-for-privacy@dont-email.me:

There are no ressistors in milliohm values nor are there any marked as such, so upper or lower case m in resistance means MEGA.

It would charge faster on our more manly 230V, but would run 17% slower on our somewhat less frenetic 50Hz.

Cheers

Clive Arthur wrote in news:q46grk$lvq$ snipped-for-privacy@dont-email.me:

Our charging systems over here operate on 240 volts.

Volts are volts in metric or imperial. And DC switchers do not feed out 50 or 60 Hz to the prius so that doesn't matter either.

Manly? GTFUC.

Of course standards are good. If they weren't so good, we wouldn't have so many! Often for the same things.

Rick C.

Ship it by train.

Why are people paranoid about dots falling on the floor? Mine never do. It's an amateur thing. One of the first thing they taught us in engineering school was to always use leading zeroes and to draw healthy decimal points.

Imagine submitting a scientific paper to a serious journal, and using this goofy notation. 6kg51. 45v/m88. 299792km/s458.

Or maybe 222792km458/s ?

No wonder that lots of scientists don't respect engineers.

snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:

My kilogram reference standard is in the shape of a sphere.

The rest of the world is still using a cylinder which has apparently lost some of its mass over time.

I think all applications dealing with numbers should accept formats like '10n' for 1e-8. However, there should never be multiple SI multiplier prefixes in one expression.

I made a (text terminal) calculator program that uses this notation. It will print light speed as '299.8M' and Boltzmann's constant as '13.81y'.

I don't see why '4k7' for 4700 is amateur. It's perfectly clear. You naturally use it for money amounts too: 'Three dollars 99'. '0.01uF' instead of '10nF' is goofy alright.

Jeroen Belleman

Certainly. SI prefixes are accepted standard.

c = 299.8 m/s.

I don't hear that. I certainly don't see 3$99 in writing anywhere. Even grocery stores can afford high quality decimal points.

It's increasingly rare.

One metre seventy three is about five foot eight and three pounds forty seven is about four dollars thirty four.

You're right, it'll never catch on.

Cheers

Of course we do. I do mine in PowerBasic and other people do stuff in Python. PADS outputs nice ascii netlists and BOMs, and it's easy to access our inventory database.

I also wrote a netlist compare program, which will compare schematics and PCBs in any combination. It works a lot better than the native PADS functions.

I have another program that searches inventory for a pair of resistors with a desired ratio and thevenin impedance. That saves me a ton of time and helps minimize BOM items and feeder loading.

And unnecessary and ugly.

On a schematic, it is reasonable to assume that resistors values are in ohms, caps in farads, and inductors in henries, with the numeric value in standard scientific/engineering form.

Aren't road signs still Imperial in the UK?

How about groceries and such? What units do they buy milk and potatoes in?

Is beer and liquor served by the ml?

John Larkin wrote

The function of circuit diagrams is to be human readble. The 2k2 and 3k3 notations are very easy to read. Anybody can understand that (OK almost anybody). My 200m$ worth.

The world is in flux.

Do you make money from posting mamazone links? I noticed the 'sponsor' word in your links. Does it pay the rent?

You mean like it is here? The US liquor industry is one that went metric a long time ago.

Rick C.

That one predates SI.

Cheers

Phil Hobbs

Yes, I know that.

I know that 601 ohms is not a standard value. 600 ohms is not an E series value, but is not unusual. Just like 50 ohms.

Of course I can and I did before posting just to be sure. The point I am making is that this was not a high precision resistor so there was no need for it to be a special value

Not my procurement system. The one belonging to a very large manufacturer.

Big companies say what they want and suppliers deliver, even if it doesn't make sense. Every individual resistor value goes out to tender with some large manufacturers.

Try again. A resistor marked 601 would be 600 ohms. The procurement people ended up buying 601 ohm resistors when the designers intended

John

Some designers seem to mark their resistors according the color bands on the resistor.

Of course, none of these are standard E-series.

It's a velocity, so 299.8 Mm/s. My calculator knows nothing about units, only numbers and SI prefixes.

Jeroen Belleman