With this calculator you can easily convert from HP to VA, unlike other calculators in this one we take into account the efficiency of the motors.
In addition, the formula is shown with some examples and equivalences in a table with the main conversion steps for HP to VA.
HP to VA conversion formula:
- P.F=Power factor.
How to convert Hp to VA in only 3 step:
Multiply Hp (Horsepower) by 746. Example, if you have 100 hp multiply by 746 and you get 74600.
Divide step 1 between step 2, the result will be: 103.611VA ((100×0.746)/(0.9×0.8) = 103.611VA).
Definition S (VA), F.P, H.P and Efficiency:
VA: A volt-ampere, commonly referred to as a VA, is commonly used as a unit of power in obtaining the electrical capacity of circuit breakers, uninterrupted power supplies and wirings.
VA is larger than Watts because loads are inductive such as motors, discharge lighting, reactors and more current is required to keep the magnetic field energized than is -turned into heat (W).
Inductive devices or loads such,. as tansformers and motors having power factor less than 1.0 are generally rated in VA.
Hp: The horsepower (hp) is a unit in the foot-pound-second ( fps ) or English system, sometimes used to express the rate at which mechanical energy is expended. It was originally defined as 550 foot-pounds per second (ft-lb/s). Defined by James Watt (1736-1819) the inventor of first practical steam engine.
A power level of 1 hp is approximately equivalent to 746 watt s (W) or 0.746 kilowatt s (kW).
Motor Efficiency: Electric motor efficiency is the ratio between power output (mechanical) and power input (electrical).
Mechanical power output is calculated based on the torque and speed required (i.e. power required to move the object attached to the motor), and electrical power input is calculated based on voltage and current supplied to the motor.
Mechanical power output is always lower than the electrical power input, as energy is lost during conversion (electrical to mechanical) in various forms, such as heat and friction. Design of an electric motor aims to minimize these losses to improve efficiency.
P.f: Power factor is the ratio of working power to apparent power. It measures how effectively electrical power is being used. A high power factor signals efficient utilization of electrical power, while a low power factor indicates poor utilization of electrical power.
Power Factor is the cosine of the phase angle between current and voltage.
Power Factor is the ratio of true power to apparent power.
Typical Un-improved Power Factor by Industry:
|Oil field Pumping||0.40-0.60|
|Tool, dies, jigs industry||0.65-0.75|
Typical power factor of common household electronics:
|Electronics device||Power Factor|
|Magnavox Projection TV – standby||0,37|
|Samsung 70″ 3D Bluray||0,48|
|Digital Picture Frame||0,52|
|Magnavox Projection TV||0,58|
|Digital Picture Frame||0,6|
|Digital Picture Frame||0,62|
|Digital Picture Frame||0,65|
|Philips 52″ Projection TV||0,65|
|Digital Picture Frame||0,73|
|Sharp Aquos 3D TV||0,95|
|Element 41″ Plasma TV||0,99|
|Current large, flat-screen television||0,96|
|Windows-mount air conditioner||0,9|
|Legacy CRT-Based color television||0,7|
|Legacy flat panel computer monitor||0,64|
|While-LED lighting fixture||0,61|
|Legacy laptop power adapter||0,55|
|Fluorescent lamps (uncompensated)||0,5|
|Fluorescent lamps (compensated)||0,93|
Typical Motor Power Factors:
|(hp)||(rpm)||1/2 load||3/4 load||full load|
|0 – 5||1800||0.72||0.82||0.84|
|5 – 20||1800||0.74||0.84||0.86|
|20 – 100||1800||0.79||0.86||0.89|
|100 – 300||1800||0.81||0.88||0.91|
Electrical motors constructed according NEMA Design B must meet the efficiencies below:
|Power||Minimum Nominal Efficiency1)|
|1 – 4||78.8|
|5 – 9||84.0|
|10 – 19||85.5|
|20 – 49||88.5|
|50 – 99||90.2|
|100 – 124||91.7|
Reference // http://www.engineeringtoolbox.com
Hp to VA conversion table: