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Ampacity

Ampacity

Ampacity

(OP)
In another forum I saw the word "ampacity" used instead of the term "current carrying capacity"

This is new to me.

I appreciate the brevity, but it must be one of the clumsiest bits of jargon I have seen.

Can anyone think of a better word for this property of a conductor?


Jeff

RE: Ampacity



I think that 'ampacity' is a good expression. It conveys the exact meaning, it is short, it is not ambiguous.

Any other word seems to be worse, 'curpacity' or (forgive me) 'curability' or 'cubility' or whatever one can concoct are catastrophes compared to ampacity.

Of course, 'current carrying capacity' can be used like before, and no one will object to that, I think.

RE: Ampacity

I've only ever seen the term used in material from North America.  It's a bit like "faucet' and 'candy' and 'cookie' and many other terms found almost exclusively in US English.  

It seems to me to only be necessary for regulators trying to define some legal limit to current flow that should not be exceeded.  The wire itself has no physical limit to its capacity to carry current, at least not in the same sense as a bucket has a fixed water carrying capacity.

What single word would one use for the maximum allowable water flow rate in a pipe?  Flowacity?  Cumecacity?

Bung
Life is non-linear...

RE: Ampacity

Quoting the McGraw-Hill Dictionary of Scientific and Technical Terms (4th Ed. 1989):
 
ampacity Current-carrying capacity in amperes; used as a rating for power cables.

RE: Ampacity

Isn't the physical current carrying capacity limitation of a wire when it glows red hot, and essentially destroys itself???  I am not an electrical expert, just a ME who has inadvertently shorted a few wires when I wish I hadn't.  Looked limiting to me.

For my part as an ME, (who has lots of wires connected to my mechanical devices in a variety of voltages) ampacity conveys the perfect message to me.

rmw

RE: Ampacity

That's fine if you're planning to use youe wires as fuses.

Generally, as with mechanical structures, there is a design limit that provides adequate margin for the design constraints.  Such is the case for ampacity.

TTFN

RE: Ampacity

(OP)
OK, it appears to be a commonly used American term. What is wrong with "rating" or "rated"? Such as "16 sq mm cable is rated at 65 amps"

Is ampacity defined in standards, ie for a conductor in free air, in a multi core cable, buried underground, or is it a vague term describing the point where it becomes a fuse?

regards
Jeff

RE: Ampacity

using the wire as a fuse was totally unintentional, (and costly in some cases)

rmw

RE: Ampacity

ampacity refers to a steady-state current carrying limit.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: Ampacity

"Ampacity" is recognized by the IEEE. A cable may have several ampacities depending on how it's installed. "Rating" is fine, but by itself it is rather unspecific since it could apply to voltage, temperature, impedance, etcetera. Guess we need qualifiers for both terms, but "ampacity" needs fewer.

RE: Ampacity

Danger 50,000 ohms!

Early last century my Dad witnessed a "device" used by a medical quack with the above label.  I think the quack who used this device also used the term ohmage.

Jesus is THE life,
Leonard

RE: Ampacity

long live the resistance.

RE: Ampacity

Pay ohmage to the resistance.

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Ampacity

I heard one the other day from an Elctrical Engineer ...
"electronical" schematic. What does that mean?

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP0.1 / PDMWorks 05
ctopher's home site

RE: Ampacity

Probably a schematic that can be read by electronical means - I have been told that there are so called Data Machines that probably can be used for that purpose.

RE: Ampacity

As far as I know, there is no such official word. If there is, I would like to know a reference to it. Thank you.

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP0.1 / PDMWorks 05
ctopher's home site

RE: Ampacity

It was supposed to be a joke...

RE: Ampacity

While working on an old Univac main frame computer, one of the sections of the internals was refered to as the Arithmetic Register.

Many would pronounce this as arith-me-tic, but our instructor made us say arith-me'-tic (sounding like 'medic').  He said it sounded more "high-tech."

"I think there is a world market for maybe five computers."
Thomas Watson, chairman of IBM, 1943.
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Ampacity

skogsgurra, I know. thanks

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP0.1 / PDMWorks 05
ctopher's home site

RE: Ampacity

Mango--depends on whether "Arithmetic" is adjectival or nominal.

Hg

RE: Ampacity

Electronical sounds very "Monty Burns".

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Ampacity

never thought of that, funny

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP0.1 / PDMWorks 05
ctopher's home site

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