Power Calculator

Power Calculator

TO FIND	DIRECT CURRENT	ALTERNATING CURRENT
		Single Phase	Three phase
Amperes When Horsepower (Input) is Known	HP x 746 Volts x Efficiency	HP x 746 Volts x Efficiency x PF	HP x 746 Volts x 1.73 x PF
Amperes When Kilowatts is Known	KW x 1000 Volts	KW x 1000 Volts x PF	KW x 1000 Volts x 1.73 x PF
Amperes When kva is Known		KVa x 1000 Volts	KVa x 1000 Volts x 1.73
Kilowatts	Amperes x Volts 1000	Amperes x Volts x PF 1000	Amperes x Volts x 1.73 x PF 1000
kva		Amperes x Volts 1000	Amperes x Volts x 1.73 1000
Power Factor		Kilowatts x 1000 Amps x Volts or KWA Kva	Kilowatts x 1000 Amps x Volts x 1.73 or KWA Kva
Horsepower (Output)	Amps x Volts x Efficiency 746	Amps x Volts x Efficiency x PF 746	Amps x Volts x 1.73 x Efficiency x PF 746

These calculators will assist you in determining what size generator you may require or how to convert one unit of electricity to another.

They calculate:

Amperes when kVA is known
Converting kVA to kW
Converting kW to kVA
Converting kW to HP
kVA Required to run motors

Guide to units:

HP = Horsepower
kW = Kilo Watts
kVA = Kilo Volt Amps
I = Ampere or Current
V = Volts
PF = Power Factor

Sizing Data - Power Consumption

Calculating Ampere (I), given kVA.
Phase 1, 2, 3	Generator kVA	Volts Required	=	Ampere I

Converting kVA to kW
kVA	=	kW

Converting kW to kVA
kW	=	kVA

Converting kW to HP
kW	=	HP

What size genset is needed to start a 3 phase electric motor Direct on Line (DOL) start
HP of Motor	=	Generator kVA Required

Generator Size to Start Motors

Instructions: You only need to fill in the columns coloured in blue.
Fill in the HP of the motor(s) in their starting squence, select the start method (Direct On Line or Star Delta) and press Evaluate. The required generator size will then be displayed at the bottom.

3 Phase (415 volt @ 50Hz)
1 Phase (240 volt @ 50Hz)

Starting Sequence Motor HP Start Method
DOL / StarDelta Run Variable Phase Current Starting Value Total Run Current Total Start Current

1 /

2 /

3 /

4 /

5 /

6 /

Generator Size for Starting with: kVA*

Generator Size for Running with: kVA*

Generator Size Recommended: kVA*

* Please NOTE the above calculations are an estimate only because other factors such as site conditions, motor efficiencies and iron losses are not taken into consideration.

Hosted by www.Geocities.ws