Horsepower (metric) explained
Metric horsepower is a unit of power commonly used in automotive and mechanical engineering contexts, especially in countries that utilize the metric system. Defined as the power required to lift a 75-kilogram mass one meter in one second, it equates to approximately 735.5 watts. This unit provides a practical measure for engine output and mechanical performance in various applications.
Symbol
The symbol for metric horsepower varies by language and region. Common representations include PS (German: Pferdestärke), cv (Italian: cavallo vapore), ch (French: cheval-vapeur), and pk (Dutch: paardenkracht). Despite the different abbreviations, they all denote the same unit of power.
Comparison with Other Horsepower Units
While metric horsepower is widely used, several other definitions of horsepower exist, each tailored to specific contexts:
- Imperial (Mechanical) Horsepower: Defined as 550 foot-pounds per second, equivalent to approximately 745.7 watts. Predominantly used in the United States and the United Kingdom.
- Electric Horsepower: Standardized at exactly 746 watts, commonly used to rate electric motors.
- Boiler Horsepower: Represents the energy required to evaporate 34.5 pounds of water at 212°F in one hour, equal to about 9,809.5 watts. Utilized in steam boiler applications.
- Water Horsepower: Measures the theoretical power required to move water, calculated based on flow rate and head height, primarily used in hydraulic engineering.
Applications and Fields of Use
Metric horsepower is extensively employed in:
- Automotive Industry: To denote engine power in vehicles, especially in Europe and Asia.
- Mechanical Engineering: For specifying the output of various machinery and equipment.
- Marine Engineering: To describe the power of ship engines and propulsion systems.
Measurement Instruments
Instruments and methods used to measure power in metric horsepower include:
- Dynamometers: Devices that measure force, torque, or power output of engines.
- Engine Test Benches: Setups that allow for comprehensive testing of engine performance under controlled conditions.
Origin
The concept of horsepower was introduced by Scottish engineer James Watt in the late 18th century to compare the output of steam engines with the power of draft horses. The metric version was later standardized to align with the International System of Units, facilitating its adoption in countries using the metric system.
FAQs
Is there a difference between PS and hp?
Yes, PS (Pferdestärke) refers to metric horsepower, approximately 735.5 watts, while HP (horsepower) typically refers to imperial horsepower, approximately 745.7 watts. The difference arises from the distinct definitions in metric and imperial systems.
Can I use metric horsepower for electric motors?
While possible, it's uncommon. Electric motors are typically rated in kilowatts or electric horsepower (746 watts). Using metric horsepower for electric motors is not standard practice.
Are vehicle power ratings in Europe based on metric horsepower?
Yes, many European countries use metric horsepower to rate vehicle engine power, although kilowatts are also commonly provided for standardization with the SI System.
How do I convert horsepower (metric) to other power units?
Use the links below for easy conversions from horsepower (metric) to other power units available on this website.
- Horsepower (metric) to watts
- Horsepower (metric) to kilowatts
- Horsepower (metric) to horsepower (electric)
- Horsepower (metric) to horsepower (boiler)
- Horsepower (metric) to horsepower (imperial)
- Horsepower (metric) to horsepower (water)
- Horsepower (metric) to btus (international table) per hour
- Horsepower (metric) to btus (international table) per minute
- Horsepower (metric) to btus (international table) per second
- Horsepower (metric) to mbh
- Horsepower (metric) to btus (thermochemical) per hour
- Horsepower (metric) to btus (thermochemical) per minute
- Horsepower (metric) to btus (thermochemical) per second
- Horsepower (metric) to tons-of refrigeration
- Horsepower (metric) to kilocalories (international table) per hour
- Horsepower (metric) to kilocalories (international table) per minute
- Horsepower (metric) to kilocalories (international table) per second
- Horsepower (metric) to calories (international table) per hour
- Horsepower (metric) to calories (international table) per minute
- Horsepower (metric) to calories (international table) per second
- Horsepower (metric) to kilocalories (thermochemical) per hour
- Horsepower (metric) to kilocalories (thermochemical) per minute
- Horsepower (metric) to kilocalories (thermochemical) per second
- Horsepower (metric) to calories (thermochemical) per hour
- Horsepower (metric) to calories (thermochemical) per minute
- Horsepower (metric) to calories (thermochemical) per second
- Horsepower (metric) to foot pounds-force per hour
- Horsepower (metric) to foot pounds-force per minute
- Horsepower (metric) to foot pounds-force per second
- Horsepower (metric) to ergs per second
- Horsepower (metric) to kilovolt-amperes
- Horsepower (metric) to volt-amperes
- Horsepower (metric) to newton-meters per second
- Horsepower (metric) to joules per second
- Horsepower (metric) to quettawatts
- Horsepower (metric) to ronnawatts
- Horsepower (metric) to yottawatts
- Horsepower (metric) to zettawatts
- Horsepower (metric) to exawatts
- Horsepower (metric) to petawatts
- Horsepower (metric) to terawatts
- Horsepower (metric) to gigawatts
- Horsepower (metric) to megawatts
- Horsepower (metric) to hectowatts
- Horsepower (metric) to dekawatts
- Horsepower (metric) to deciwatts
- Horsepower (metric) to centiwatts
- Horsepower (metric) to milliwatts
- Horsepower (metric) to microwatts
- Horsepower (metric) to nanowatts
- Horsepower (metric) to picowatts
- Horsepower (metric) to femtowatts
- Horsepower (metric) to attowatts
- Horsepower (metric) to zeptowatts
- Horsepower (metric) to yoctowatts
- Horsepower (metric) to rontowatts
- Horsepower (metric) to quectowatts