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Motor has full load current of 39.5 Amps the actual current measured on each phase is 25 Amps in delta you need to know if the motor is below its full capacity Any calculations to help you compare?
First, check the nameplate on the motor. The FLA or full load amperage is the required start up current and is typically 125-150 % higher than the running load amperage (RLA). So a current draw of 39.5 while starting would be normal for a motor drawing 25 A in run mode.You don't need any calculations. If the stated RLA is close to 25 A and you're drawing 25 A then the motor is fine. As long as you're supplying the correct full voltage required by the motor, it will operate at "full capacity". There are numerous formulas for motors. I would need to know the motor's horsepower, voltage, whether it's single or three phase and its stated efficiency (EFF on the nameplate), the FLA and RLA to tell you if the motor is running properly or if it's going bad.
How do you measure RLA on a 230-1 phase motor do you add each the amps measured on each leg?
You can't measure an RLA. It is determined by the factory that manufactured the compressor. To answer your other question, a 230 volt load is actually using both legs as part of the circuit, so you can measure either leg with a current meter but there is no need to add them up.
How do you run a motor 208 volts ac in a 230 volts suply?
If your motor is rated for only 208 volts you may not be able to use 230 volts for it. It will run, but may shorten the life of the motor. Motors are rated with a 10% tolerance for voltage. This means that a 208 volt motor has a maximum voltage rating of 228.8 volts. So measure you voltage supply and see if it is below 228.8 with a good RMS voltmeter. If it is, you are good to go. If it is not there are two ways to make it work. 1. Put a high wattage ballast resister in series with the supply voltage to drop the voltage to the motor within range of 187.2 to 228.8 volts. To determine the value of the resistor take the Horse Power of the motor and multiply it by 746. This will give the wattage of the resistor, use one at least 20% larger. Next take the Rated Load Amps (RLA) or Full Load Amps (FLA) of the motor and divide it into the difference between 230 (voltage supply) and the 208 (rated motor voltage), this will get you close to the resistance value of the Ballast resistor you need to use. So a 1/2 HP motor with a 1.2 RLA will require about a 18 ohm, 500 watt ballast resistor. This is not the recommended method, but will work. 2. Install a Buck & Boost transformer rate for the HP of the motor that will Buck the supply voltage for the motor down to 208 volts. This is the recommended way and the only way it should be done. Any good commercial electrical supply house can help you properly size the transformer that you will need.
How do you find the no load amp rating of a motor?
Full load amps is found on the motor's nameplate, and is unique to that particular brand and model number. A Magnetec 2hp motor will draw different amps than a Baldor 2hp, etc. There are high efficiency motors, and not so high as well. Consult the nameplate. If you want a "rule of thumb" to estimate the RLA (Running Load Amps - this is the term most often found on the nameplate - same as full load amps), then use this: Figure about 1400 watts per horsepower. Divide Watts by volts to get Amps, for example: * 3hp motor, 120V * 3hp X 1400 W = 4200 W * 4200 W / 120 V = 35 A This formula is only for single-phase motors! I looked up a typical 3hp 120 V Baldor motor in the Grainger's catalog, and the RLA for it was 32.0, so this will get you in the ballpark. I have seen 3hp 120 V motors as low as 25 A and as high as 40, so DO NOT use the rule of thumb to size branch circuit conductors or overcurrent protection! For 3-phase motors: Figure about 1100 watts per horsepower (3-phase is a little more efficient). Divide Watts by Volts, then divide the answer by 1.73 to get Amps, for example: * 3hp motor, 208V 3Ph * 3hp X 1100 W = 3300 W * 3300 W / 208 V = 15.86 * 15.86 / 1.73 = 9.16 A This formula is only for 3-phase motors! My Grainger's catalog motor with the same Voltage and HP had a nameplate rating of 8.34 A.
Which type of motor is used in wet grinders?
A universal motor is used to operate a food mixer.
What is 15 RLA to Fla?
fla/rla
What does rla mean on an air compressor?
Rated load amps = rla
What is RLA in Electrical Terms?
RLA in eletrical terms is Reading Language Arts.
What is rla and lra on compressors?
rla run load amps lra locked rotor amps.
WHAT IS RLA?
run load ampers
What does RLA stand for?
Republican Literation Association
Motor has full load current of 39.5 Amps the actual current measured on each phase is 25 Amps in delta you need to know if the motor is below its full capacity Any calculations to help you compare?
First, check the nameplate on the motor. The FLA or full load amperage is the required start up current and is typically 125-150 % higher than the running load amperage (RLA). So a current draw of 39.5 while starting would be normal for a motor drawing 25 A in run mode.You don't need any calculations. If the stated RLA is close to 25 A and you're drawing 25 A then the motor is fine. As long as you're supplying the correct full voltage required by the motor, it will operate at "full capacity". There are numerous formulas for motors. I would need to know the motor's horsepower, voltage, whether it's single or three phase and its stated efficiency (EFF on the nameplate), the FLA and RLA to tell you if the motor is running properly or if it's going bad.
How do you measure RLA on a 230-1 phase motor do you add each the amps measured on each leg?
You can't measure an RLA. It is determined by the factory that manufactured the compressor. To answer your other question, a 230 volt load is actually using both legs as part of the circuit, so you can measure either leg with a current meter but there is no need to add them up.
What is the name of the federal agency that is charged with administering the RLA?
National Mediation Board
Who owns RLA?
H C owns it and it stands for Republican Literation Association
What is the root word for organ?
organ
How do you run a motor 208 volts ac in a 230 volts suply?
If your motor is rated for only 208 volts you may not be able to use 230 volts for it. It will run, but may shorten the life of the motor. Motors are rated with a 10% tolerance for voltage. This means that a 208 volt motor has a maximum voltage rating of 228.8 volts. So measure you voltage supply and see if it is below 228.8 with a good RMS voltmeter. If it is, you are good to go. If it is not there are two ways to make it work. 1. Put a high wattage ballast resister in series with the supply voltage to drop the voltage to the motor within range of 187.2 to 228.8 volts. To determine the value of the resistor take the Horse Power of the motor and multiply it by 746. This will give the wattage of the resistor, use one at least 20% larger. Next take the Rated Load Amps (RLA) or Full Load Amps (FLA) of the motor and divide it into the difference between 230 (voltage supply) and the 208 (rated motor voltage), this will get you close to the resistance value of the Ballast resistor you need to use. So a 1/2 HP motor with a 1.2 RLA will require about a 18 ohm, 500 watt ballast resistor. This is not the recommended method, but will work. 2. Install a Buck & Boost transformer rate for the HP of the motor that will Buck the supply voltage for the motor down to 208 volts. This is the recommended way and the only way it should be done. Any good commercial electrical supply house can help you properly size the transformer that you will need.
