What does SFA mean on motor nameplate?

What does SFA mean on motor nameplate?

Service Factor Amps
Service Factor Amps, or S.F.A., represents the amount of current the motor will draw when running at the full Service Factor. In the example nameplate, the S.F.A. is eight amps at 230 volts. Continually exceeding the S.F.A. shown on the nameplate can shorten motor life.

What information is on a motor nameplate?

The nameplate-defined parameters for the motor – such as power factor, efficiency, torque and current – are at rated voltage and frequency. When the motor is used at other voltages than the voltage indicated on the nameplate, its performance will be affected.

What does 1.15 sf mean on a motor nameplate?

Motor Service Factor
Motor Service Factor (SF) is the percentage of overloading the motor can handle for short periods when operating normally within the correct voltage tolerances. This means that a 10-hp motor with a 1.15 SF could provide 11.5 hp when required for short-term use.

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.

What does SF mean on a motor?

service factor
As per the standards, a motor’s nameplate should indicate the service factor as “SF”. The standard which defines the service factor for motors and generators is the MG-1 standard, which in turn defines powers and speeds.

How do I find my Fla rating?

Formulas

1. Single Phase AC Motor FLA (Amperes) = (P [kW] × 1000) / (V × cos ϕ)
2. Single Phase AC Motor FLA (Amperes) = (P [HP] × 746) / (V × cos ϕ × η)
3. Three Phase AC Motor FLA (Amperes) = (P [kW] × 1000) / (V × 1.732 × cos ϕ)
4. Three Phase AC Motor FLA (Amperes) = (P [HP] × 746) / (V × 1.732 × cos ϕ × η)

Which of the following information is available on the name plate of a motor Mcq?

Explanation: Name plate of the motor shows rated values i.e. rated speed, rated current, rated voltage. It also shows output power available at shaft when all other quantities are set to rated values.

How do I find my motor details without nameplate?

Use a strobe tachometer to determine motor RPM and then set up a generic motor in the database for that RPM. If loading cannot be provided by the operator use the acquired data and RPM to approximate loading. You can view the power factor for a value around 88 to 92 to approximate full 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 the SF rating on a motor?

Motor service factor (SF) is the percentage multiplier that a motor can handle for short periods of time when operating within its normal voltage and frequency tolerance. In other words, it is a fudge factor that give extra horsepower when it’s occasionally needed.

What do voltages mean on a motor nameplate?

This data tells you at which voltage the motor is made to operate. Nameplate-defined parameters for the motor such as power factor, efficiency, torque and current are at rated voltage and frequency. When the motor is used at other voltages than the voltage indicated on the nameplate, its performance will be affected. Voltage on motor nameplate

What is the SFA value on a motor?

The SFA value found is 21.7, the FLA is 17.3. The motor strater overload relay occasionaly trips out…. It’s the service factor amps. It looks as if your motor has a 1.25% servicew factor. 17.3 x 1.25=21.6a

Why are motor nameplates not rated at service factor?

Motors are built in accordance with NEMA MG1, which states that when operated in their service factor rating the insulation will degrade 2x faster then when operated at the normal nameplate ratings. I’d say that is more then a generally accepted principle, and that is definitely a technical reason to not do so.

What should the service factor be on a polyphase induction motor?

Nominal efficiency mist be included on polyphase induction motor name-plates when required by NEMA. Service Factor (SF). The service factor is only required ion a nameplate if it is higher than 1.0. Industry standard service factors include 1.0 for totally enclosed motors and 1.15 for open motors.