Such a measure as horsepower has been used in our country for a long time to determine power, becoming familiar and understandable. However, more and more states, including Russia, are abandoning its official application. A single measure of power that has a common equivalent throughout the world is watt. Despite this, in areas where internal combustion engines are used, the calculation and designation of their power is still carried out in horsepower. Even the transport tax and compulsory motor liability insurance in our country are calculated according to these units. In this regard, vehicle owners have to periodically convert kilowatts to horsepower.
Watts and kilowatts as units
Watt (W or international W) is a measure of power included in the International System of Measurement (SI). 1 watt is determined by the work in one joule, produced in one second. Watts are also expressed in terms of the ratio of other units - a kilogram moved to a distance of 1 meter in 1 second, newton per meter in 1 second, volt-ampere.
Using watts, radiation fluxes are measured, heat and sound energy, ionizing radiation, electric current power. A kilowatt (kW or kW) is equal to 1000 watts.
Watt is named after the scientist and inventor James Watt (Watt) and entered into official circulation at the end of the 19th century. Prior to this, the calculation of power was carried out in horsepower, which he determined in the process of practical experiments and measurements.
What is called horse power
Horsepower (hp) is a standard measure that is not part of a single International System of Measurement (SI). It is not common throughout the world. How many kilowatts per horsepower will be different depending on the measurement system adopted in the country's circulation. If it is metric, then meters and kilograms will be used to calculate horsepower, or this unit will be calculated using feet and pounds to measure length and weight. The resulting digital value will be different.
Features of calculating horsepower in different measuring systems
In the metric system, horsepower is defined as the movement of a load weighing 75 kg over a distance equal to 1 meter in 1 second.
Thus, the metric drug = 735.49875 W = 0.74 kW.
When calculated in feet and pounds, this figure is equal to the ratio when moving a weight of one pound per 33,000 feet in one minute or one pound in 550 feet in one second.
In England and the USA, PM = 745.69987158227022 W = 0.75 kW, and in relation to the identical metric unit of measurement = 1.014.
Also in the energy and industry, there are concepts:
- electric horsepower equal to 746 kW;
- boiler l with., equal to 33 475 BTU (British thermal unit) / h = 9809.5 watts.
Respectively:
- 1 kW is 1.3596 liters. with. (metric);
- 1 kW is 1.3783 hp (English);
- 1 kW is 1, 34048 l. with. (electrical unit).
In different world states, horsepower is designated differently:
- l with. - Russia,
- hp - English speaking countries,
- PS - Germany,
- CV - France,
- pk - Netherlands.
The difference in the ratio of kilowatts and horsepower for different methods of measurement
The method of measuring actual power directly affects the numbers obtained when converting kilowatts to horsepower.
This is especially true for calculating the real power of vehicle engines.
There are concepts of gross and net horsepower.
When conducting gross measurements, engine power is evaluated at the bench. It does not take into account the work of related systems that ensure the functioning of the machine as a whole - a generator, a cooling system pump, and so on.
Measurement of net power at the stand is carried out with a reference to its work in normal conditions, that is, with all auxiliary systems.
Accordingly, the first value will always be larger in numbers, but will not show the real power of the mechanism.
As a result, if the kilowatts indicated in the documentation for the technical tool are converted into horsepower in the first way, we can estimate the amount of work produced exclusively by the engine. To obtain real information about the power of a transport or other unit, this will not be very useful, since the error will be from 10 to 25%.
Also, such measurements are disadvantageous for determining the actual performance of the engine when calculating transport taxes and purchasing OSAGO, since higher rates are provided for higher rates, and the calculation is made taking into account each horsepower.
For accurate measurement of the value, there are special devices - dynamometers. The services of the so-called dynamostands (dynamometer stands) are provided by some car services.
In addition, quite expensive electronic devices are manufactured that are installed directly in the vehicle.
Independently, but with a certain error, it is possible to measure the engine power in kilowatts or horsepower using specialized computer applications by connecting a laptop via a cable to the car and measuring performance at different speeds. The measurements will contain some error, which the program also informs after the calculations.
How to quickly convert kilowatts to horsepower
To carry out these calculations is simple and short, if you know the formula and the system in which horsepower will be determined.
To calculate specific values, you can use one of the many online converters adapted to convert values ββfrom one measurement standard to another. It is enough to enter the original value in the corresponding line.