plate
Senior Member
- Location
- South East PA
How about getting rid of the use of "amperage". I would rather people use amps, amperes, or ampacity, depending on the sentence.
celtic said:No way.... the look on a person's face when you say "I'd be happy to check your shorts" is priceless :grin::grin::grin:
The first question I ask an engineer that I just met is this: "When you open something, does it cause flow or prevent flow?" That way, I can tell if I am talking to an Electrical Engineer or a Mechanical Engineer. :grin:kc8dxx said:I work with hydraulics on occasion. Normally Open in the Hydraulics world means the oil is flowing. Normally Open in the Electrical world means the electrons are not flowing. Drives me nuts.:grin:
If you buy an NEC-related book from Mike Holt, you will get a free sticker containing the text of "Charlie's Rule." It also has a sketch of a person reading an NEC book, and wearing a shirt with the text, "Electrician, qualified to remove your shorts." You may credit me with "Charlie's Rule," but do not credit me with (or blame me for) the art work.electricman2 said:Actually saw this on an EC's van once "Let us check your shorts"
My problem is with the word "normal." If you have two pumps, and switch from one to the other every other day, which one is "normally on"? If a valve is open when pumping water to one tank, and is closed when pumping to another tank, is the valve "normally open" or "normally closed"? If a switch has a contact that is open, when the switch is "off," and closed, when the switch is "on," and if the "usual" (I won't say "normal" in this context) condition of the system is for this switch to be "on" for 99.999% of the time, is that contact "normally open" or "normally closed"?stickboy1375 said:What else would you call something that is normally in a certain position?
charlie b said:Highest on my list would be the phrases "normally open," normally closed," and anything similar.
Yea, that part I might have guessed. :roll:GeorgeB said:An open valve or closed contact passes, a closed valve or open contact blocks
charlie b said:(Replying to my comment about "normally open":
My problem is with the word "normal." If you have two pumps, and switch from one to the other every other day, which one is "normally on"? If a valve is open when pumping water to one tank, and is closed when pumping to another tank, is the valve "normally open" or "normally closed"? If a switch has a contact that is open, when the switch is "off," and closed, when the switch is "on," and if the "usual" (I won't say "normal" in this context) condition of the system is for this switch to be "on" for 99.999% of the time, is that contact "normally open" or "normally closed"?
charlie b said:
The first question I ask an engineer that I just met is this: "When you open something, does it cause flow or prevent flow?" That way, I can tell if I am talking to an Electrical Engineer or a Mechanical Engineer. :grin:
John Valdes said:But ?normally? is referring to ?not energized.? Unless noted on the relay I have found this to be true.
I agree with this interpretation. But I have found that I cannot always trust my listener to interpret it the same way. Others have interpreted ?normal? as meaning the state the device can be found in, if you were to look at it while the system is operating in its usual manner.stickboy1375 said:Normal is the condition of the device before a voltage is applied... the way I look at it anyway...
charlie b said:
I agree with this interpretation. But I have found that I cannot always trust my listener to interpret it the same way. Others have interpreted ?normal? as meaning the state the device can be found in, if you were to look at it while the system is operating in its usual manner.
The way I handle the situation is that I automatically cringe, whenever I hear the word ?normally? used in the context of ?normally open.? I stop and ask the person to clarify the intended meaning of ?normally.? It is only one of many ?cringe words and phrases.? I get the same reaction when someone tells me ?I am working on it,? or ?It?s on the way,? or worst of all, ?As far as I know.?
Not to everyone. Those involved in fire alarm and security systems will call 120 volts "high voltage," and call their own power supplies "low voltage." So you are right to say it is ambiguous.John Valdes said:It is quite ambiguous to call 0-600 volts, low voltage even though it is considered that way.