What is LRA and RLA?
LRA – Locked Rotor Amps: The current you can expect under starting conditions when you apply full voltage. It occurs instantly during start up. RLA – Rated Load Amps: The maximum current a compressor should draw under any operating conditions.
What is current RLA?
Rated Load Amps (RLA) – Reference current used in contactor and wire selection for US Customers. RLA is calculated from the Maximum Continuous Current (MCC) and serves as a running current value for the compressor.
What is LRA current?
The very high current or amperage a motor draws when power is first applied, due to low counter emf. It is usually five to six times the running load amperage.
How do you calculate RLA from LRA?
A rough rule of thumb is divide that LRA by about 5. RLA doesn’t do much for you except help you size contactors. If you’re using RLA to measure compressor performance, you’d be a lot better off using the compressor manufacturer’s performance data.
What’s the difference between LRA and FLA?
FLA: Full-Load Amps: Amount of amperage drawn when motor is working at rated horsepower. RLA: Running-Load-Amps: Same as FLA. LRA: Lock-Rotor-Amps: A motor draws a surge of amperage when it starts to get the rotor rotating and to achieve the rated horsepower.
What is difference between RLA and FLA?
The running amps of a compressor are determined by the evaporator temperature, condensing temperature and the line voltage. FLA – Full Load Amps: Changed in 1976 to “RLA – Rated Load Amps”. Here’s a link to more definitions. Keep it simple to keep it cool!
What does LRA stand for on a compressor?
Locked Rotor Amps
LRA – Locked Rotor Amps: The current you can expect under starting conditions when you apply full voltage. It occurs instantly during start up. RLA – Rated Load Amps: The maximum current a compressor should draw under any operating conditions.
How do you convert LRA to Watts?
LRA (lock rotor amps) can be converted to HP using this formula: (LRA Watts x Volts)/ 746 Watts = Horsepower. You can also use the BTUh. For example, 18,000 BTUh equals 2 HP or 24,000 2.5 HP.
How is RLA calculated?
According to Underwriters Laboratories, divide the MCC by 1.56 to determine the Rated load Amperage (RLA). Often, compressor manufacturers will divide the MCC by 1.44 to determine the RLA of their compressors to meet certain other protection specifications.
What is the locked rotor current?
Locked rotor current is basically the current drawn by the motor at its rated voltage when its rotor is kept stationary or in other words rotor is not spinning or rotating. So when we start a motor, its rotor is already at rest.