Is SFA same as FLA?
Comparing the actual SFA and FLA values, SFA is about ~1.14 of FLA.
What is the SFA rating on a motor?
The SFA of a motor stands for service factor amps, and represents the overload capacity of your motor. Ultimately, SFA indicates how much your motor can run without sustaining damage.
How do you calculate amp service factor?
For example, the FLA or full load amps of the motor above is 10.8 amps at 115 volts. The service factor or S.F. is 1.5, making the service factor amps 16.2 (rounded down to 16 on the motor tag) at 115v because 10.8 x 1.5 = 16.2.
What is service factor formula?
In simple terms, the service factor is the ratio of the gearbox rated horsepower (or torque) to the application’s required horsepower (or torque). Service factors are defined by the American Gear Manufacturers Association (AGMA), based on the type of gearbox, the expected service duty, and the type of application.
What is the purpose of service factor?
Service factor – SF – is a measure of periodically overload capacity at which a motor can operate without beeing damaged. The service factor – SF – is a measure of periodically overload capacity at which a motor can operate without damage.
Why is my motor over amping?
Electrical overload or over-current is caused by an excessive current flow within the motor windings, exceeding the design current which the motor is able to carry efficiently and safely. This can be caused by a low supply voltage, resulting in the motor drawing in more current in an attempt to maintain its torque.
Is a higher service factor better?
A motor operating continuously at any service factor greater than 1 will have a reduced life expectancy compared to operating at rated nameplate horsepower. Insulation life and bearing life are reduced by the service factor load.”
What is the meaning of service factor if its value is 1.0 What does it mean?
Motor “service factor” is probably the most misunderstood value on a motor nameplate. To most it seems quite simple; if it is a 1.0 you can run a motor to 100% load, if it is 1.15, then it can be loaded to 115% of its rated load.
What is SF in gearbox?
What is a service factor exactly? It’s the ratio of horsepower your gear reducer can mechanically handle compared to the horsepower required for your application. Put simply, it is how overdesigned the gearbox is when it comes to handling the application load.
What is SF in electrical?
Motor Service Factor (SF) is the percentage of overloading the motor can handle for short periods when operating normally within the correct voltage tolerances.
Is a higher motor service factor better?
What is service factor amperage (SFA)?
The service factor amperage is the amount of current that the motor will draw under the service factor load condition. NEMA MG-1 does not require SFA to be on the nameplate. Service Factor, yes, but only if it is over 1.0.
What is the SFA value on a motor nameplate?
What is one to do with the SFA information on a motor nameplate? Can this SFA value be used as input to Square D tables to select thermal overloads? The SFA value found is 21.7, the FLA is 17.3. The motor strater overload relay occasionaly trips out….
Does the MG-1 require SFA and SF?
NEMA MG-1 does not require SFA to be on the nameplate. Service Factor, yes, but only if it is over 1.0. So if there is no mention of SF or SFA, then the motor is a 1.0SF. Either that, or it is an IEC design, and there is no such thing as Service Factor in the IEC world.
What is the difference between SFA and LRA?
Don’t confuse SFA with LRA (locked rotor amps). LRA is the current the motor will draw when the rotor is stationary, such as during startup. Service factor is simply a short-term “fudge factor” that the motor has for short periods of higher than normal load.