Horse power ( hp ) – It is unit for measuring the mechanical power. It is the rate at which the work is done.
kilo Volt Ampere ( kVA ) – It is called as an apparent power of a particular circuit. It is the unit for rating the power of the Electric circuit. It is also called as the product of the values of voltage and current in the electric circuit.
Kilo watt ( kW ) – It is the unit to measure the actual electrical power. It is also known as real power or useful power of the system.
In DC voltage devices, kVA is equal to kW because the current and voltage of the system do not go out of the phase but in AC voltage devices kVA is not equal to kW, it is slightly more. This is due to power factor of the electrical devices.
Power factor – it is the ratio of actual electrical power which can be used in electric circuit to the apparent power of the electric circuit. Power factor ranges from zero to one depending upon the type of electrical system or devices. For eg : for motor, the power factor is considered as 0.6 whereas in some electronic devices the power factor is considered as 0.8. the higher the power factor, the more efficient is the circuit because more power can be used and vice versa.
Conversion of Horse power (hp) to kilo-watt (kW)
Conversion of horse power to kilo watt is very simple. By multiplying horsepower with 746 we can convert it into watt.
Therefore, 1 hp = 746 W.
1 hp = 0.746 kW.
1) Let us consider a device having a horse power of 250 hp. We can convert it into kW by simply multiplying the above relation.
So , 250 hp = 250 x 0.746 = 186.5 kW
2) Similarly we can convert the horse power into kilowatt of a different device. Lets say an elctrical device having a horse power of 50 hp. We will have to apply the above relation for converting.
1 hp = 0.746 kW
Therefore, 50 hp = 50 x 0.746 = 37.3 kW
This is how we can calculate the value of kilowatt for any electrical device by understanding the relation of horse power and kilowatt.
For converting horse power to kVA we need to know the power factor of the electronic device. Here power factor plays an important role. kVA is the ratio of kilo watt ( kW ) to the power factor.
1 KVA =
1hp = kVA
1) For electric motor, the power factor is considered as 0.6.
1 hp = kVA = 1.243 kVA
Let us take an example of an electric motor which is having a power of 20 hp. Here we can convert it into kilo volt ampere ( kVA ) by using the above formula.
As we know, 1 hp = 1.243 kVA
Therefore, 20 hp = 20 x 1.243 kVA = 24.86 kVA.
2) for other electronic devices power factor may vary.
Let us consider an electronic device which is having a power of 15 hp and having a power factor as 0.8. Here we can convert it into kilo volt ampere ( kVA ) by using the same formula.
Therefore 1 hp = 1 x = = 0.9325 kVA
Hence , 15 hp = 15 x 0.9325 = 13.99 kVA
This is how we can calculate the value of kilo volt ampere for any electrical device by understanding the relation of horse power and kilo volt ampere.
As we already discussed about the conversion methods for horsepower, kilowatt and kilo volt ampere. Let us see some conversions in the following table –
|Hp||Kilo watt (kW)||Kilo volt ampere (kVA)|
(at power factor = 0.6)
|Kilo volt ampere (kVA)|
(at power factor = 0.8)