FLA vs. FLC

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Jraef

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Semantics, i.e. how they are used in a sentence. Example:

My motor has an FLC of 28A.
But saying "My motor has an FLA of 29A" is being redundant because "amps" is already implied by the acronym "FLA". If I say "The FLA of my motor is 28" I am being technically correct, but it sounds odd.
 

electricalperson

Senior Member
Location
massachusetts
FLC is used when you size breaker size and wire size for motors.

FLA (located on the motor) is used to size overload protection for motors

the tables in 430 part XIV are FLC and what you need to size circuit ampacity

read 430.51 and 430.31

FLA and FLC mean the same thing for the most part. but in the real world the FLA of the motor is always less than the FLC in the tables.
 

Hameedulla-Ekhlas

Senior Member
Location
AFG
Greeting all,
I had got different comment regarding to FLA vs FLC.

raider1 FLA= Full Load Amps

FLC= Full Load Current

They basically mean the same thing.

Chris

Jraef Semantics, i.e. how they are used in a sentence. Example:

My motor has an FLC of 28A.
But saying "My motor has an FLA of 29A" is being redundant because "amps" is already implied by the acronym "FLA". If I say "The FLA of my motor is 28" I am being technically correct, but it sounds odd.

Originally Posted by LarryFine
That's like AC current and DC current, PIN numbers and VIN numbers, and LCD displays.



But still I am not sure what is the exact difference. Please see below picture it shows two different current.

404ecm06fig3.jpg


Hope to make it clear this time.
 

MIEngineer

Member
Location
Michigan
The graphic follows what electricalperson said in a previous post. This graphic simply combines two purposes of fuses or circuit breakers as it mentions in 430.55. Instead of having a circuit breaker (short-circuit & ground-fault protection) and separate fuse (overload protection) the graphic is using only 1, to satisfy all three purposes, based on the motor FLA.

Note: If you read through 430.55 & 430.32(A)(1) it mentions "motor nameplate full-load current rating" which is shown on the motor as FLA.
 

kingpb

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SE USA as far as you can go
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Engineer, Registered
The graphic as stated has multiple uses. It should be noted that the "FLC" in this case is referring to the value taken from Table 430.250 for a 50Hp motor. The NEC does allow motor nameplate data to be used for certain instances, which in this example differs from Table 430.250, i.e. FLA = 60A on nameplate versus NEC FLC = 65A in Table 430.250.

So maybe it is easier to think of FLA and FLC as interchangeable terms with the same meaning, but not necessarily equal values as seen in this case.

By definition, Full Load Current: The current drawn from the line when the motor is operating at full load torque and full load speed at rated frequency and voltage.
 

Jraef

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Needless tautological redundancy. :grin:
Tautological... my new Word of the Day!

Thanks for that, I will now bore my friends and co-workers with it all day today. I have often joked that I work for the DRD, the Department of Redundancy Dept. Now I can say I am a member of ATRA, the Associated Tautologic Redundants Assoc.
 
Tautological... my new Word of the Day!

Thanks for that, I will now bore my friends and co-workers with it all day today. I have often joked that I work for the DRD, the Department of Redundancy Dept. Now I can say I am a member of ATRA, the Associated Tautologic Redundants Assoc.

Now you're being merely sophistic. Oxymoronic would have been more straightforward.
 

KP2

Senior Member
Location
New Milford, CT
FLC is used when you size breaker size and wire size for motors.

FLA (located on the motor) is used to size overload protection for motors

the tables in 430 part XIV are FLC and what you need to size circuit ampacity

read 430.51 and 430.31

FLA and FLC mean the same thing for the most part. but in the real world the FLA of the motor is always less than the FLC in the tables.

I Agree.

FLC, (Full Load Current) is what you find in Tables 430.248 - 430.250.
FLA, (Full Load Amperage) is what is marked on the motor, refered to in the NEC as the nameplate rating and is used to size the overload's.

The FLC is used to size just about everything else to do with a motor.:grin::grin::)
 

cschmid

Senior Member
FLC and FLA are basically the same; yet FLC terminology is primarily used to size the circuit and fla is normally used in conjunction with motors and used to size heaters. so yes semantics..
 
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