BillinTexas
Member
Can any one explain the why the code use two terms Full Load Current verses Full Load Amps when referenced to a motor conductor size.
Full Load Current verses Full Load Amps
- Thread starter BillinTexas
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I'll take a guess.
I think what you're seeing is the crossover between NEC "code speak" and manufacturer "speak" on motor nameplates.
The FLC vs FLA is one example.
Another example is motor voltage categories: 115, 200, 230, 460 vs the actual supplied nominal voltages: 120, 208, 240, 480
I think what you're seeing is the crossover between NEC "code speak" and manufacturer "speak" on motor nameplates.
The FLC vs FLA is one example.
Another example is motor voltage categories: 115, 200, 230, 460 vs the actual supplied nominal voltages: 120, 208, 240, 480
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- San Francisco Bay Area, CA, USA
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- Electrical Engineer
The difference in FLA / FLC is just semantics.
If I asked you, "What's the FLA of that 350HP motor?", your answer would need to be just a number, such as "440" which is sometimes an inaccurate way to communicate because it can be easily mistaken for something else, as in this case possibly for the voltage. So if I say "What is the FLC of that 350HP motor?", your answer would be "440 amps", which would be less open for misinterpretation. But really, it's a trivial thing.
There is a difference between FLA and RLA however. When dealing with a piece of equipment that is designed to do a narrowly specific job, where even the slightest abuse might have effects beyond that piece of the machine, the difference may be important. So a motor that is designed for multiple uses or variable loads, such as your compressor, has an FLA rating because you don't know what it will be used for or loaded at. Another motor, such as the fan WITH that compressor, is designed to operate exactly THAT fan at an exact air delivery, so even though technically it may have the capacity to run at higher amps, to do so may have other consequences. So the rating of the motor is expressed in the maximum that it should be allowed to run at, or Running Load Amps.
If I asked you, "What's the FLA of that 350HP motor?", your answer would need to be just a number, such as "440" which is sometimes an inaccurate way to communicate because it can be easily mistaken for something else, as in this case possibly for the voltage. So if I say "What is the FLC of that 350HP motor?", your answer would be "440 amps", which would be less open for misinterpretation. But really, it's a trivial thing.
There is a difference between FLA and RLA however. When dealing with a piece of equipment that is designed to do a narrowly specific job, where even the slightest abuse might have effects beyond that piece of the machine, the difference may be important. So a motor that is designed for multiple uses or variable loads, such as your compressor, has an FLA rating because you don't know what it will be used for or loaded at. Another motor, such as the fan WITH that compressor, is designed to operate exactly THAT fan at an exact air delivery, so even though technically it may have the capacity to run at higher amps, to do so may have other consequences. So the rating of the motor is expressed in the maximum that it should be allowed to run at, or Running Load Amps.
Bill -
What version code are you using?
I looked for a few minutes through a 2005, Art 430, found 4 references to, "full load current" - no references to "full load amps" In each case the reference was clear if flc meant the nameplate current or the Table 2xx currents. This was definitely not an exhaustive search.
Could you reference some article numbers and the version?
I recall a few cycles back there were fla and flc references, but I understood (maybe from an ill-advised instructor :-? ) these were going to be fixed.
carl
What version code are you using?
I looked for a few minutes through a 2005, Art 430, found 4 references to, "full load current" - no references to "full load amps" In each case the reference was clear if flc meant the nameplate current or the Table 2xx currents. This was definitely not an exhaustive search.
Could you reference some article numbers and the version?
I recall a few cycles back there were fla and flc references, but I understood (maybe from an ill-advised instructor :-? ) these were going to be fixed.
carl
kingpb
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- SE USA as far as you can go
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- Engineer, Registered
By default, I would like to refer anyone looking for a phrase or word definition associated with the electrical industry, to use the IEEE dictionary.
I know to many this is not the "popular" answer.
I know to many this is not the "popular" answer.
Denis said:current is measured in......
A) Volt
B) Amp
C) Ohm
D) Mho
E) Henry
F) Hertz
G) Farad
"current is measured in......"
The multimeter ?
Wait ! Wait ! Gimme another chance !
I'll go with D) Mho
OK I know M stands for mega.
Does the other part have something to do with Governor Spitzer ?
David
kingpb
Senior Member
- Location
- SE USA as far as you can go
- Occupation
- Engineer, Registered
= coulomb/sec
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