Power Calculator

If you require assistance with this Power Calculator or what generator will best suit your requirements, please don't hesitate to contact us.

Guide to units

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

Calculating Ampere (I), given kVA

Converting kVA to kW

Converting kW to kVA

Converting kW to HP

What size genset is needed to start a 3 phase electric motor Direct on Line (DOL) start

Generator Size to Start Motors

Instructions: Fill in the HP of the motor(s) in their starting sequence, select the start method (DOL - Direct On Line or Star Delta) and press Calculate. 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.

Fill out the Generator Size to Start Motors calculator above to see Generator recommendations

Sorry! No Generator sizes found matching your recommendation.

201kVA - 400kVA 3-phase 415V

36kVA - 200kVA 3-phase 415V

Over 400kVA 3-phase 415V

Portable up to 24kVA

Up to 35kVA 3-phase 415V

Up to 50kVA Single Phase

Contact us for expert advice

For a more detailed answer and qualified advice, please contact us.

Power Consumption Calculator

Appliance	Rated Watts	Rated kVA	Rated kVA
	(Appliances)	(To operate appliance)	( To start appliance)
Air Conditioner (Evaporative model)	275-1000	0.34-1.25	1.36-5
Air Conditioner (Reverse cycle)	200-2500	0.25-3.13	1-12.5
Clothes Dryer	2400	3	3
Coffee Percolator	550	0.69	0.69
Can Opener	100	0.13	0.52
Deep Freezer	500	0.63	2.52
Disposal Unit	650	0.81	3.24
Dishwasher	1000-3000	1.25-3.75	1.25-3.75
Domestic Water Pumps	275-1000	0.34-1.25	1.36-5
Exhaust Fan	40	0.05	0.2
Food Processor	500	0.63	2.52
Floor Polisher	350	0.44	1.76
Frypan	1400	1.75	1.75
Hair Dryer	1500	1.88	1.88
Hotwater Service	2500-3000	3.13-3.75	3-13-3.75
Iron	800-1500	1-1.88	1-1.88
Kettle or jug	1600-3000	2-3.75	2-3.75
Lights	25-200	0.03-0.25	0.03-0.25
Microwave	1500	1.88	1.88
Oven	4000-8000	5-10	5-10
Radio	60	0.08	0.08
Radiator	1000-2500	1.25-3.13	115-3.13
Refrigerator (home)	300	0.38	1.52
Sewing Machine	60	0.08	0.32
Space Heater	2000	2-5	2.5
Television	75-200	0.09-0.25	0.09-0.25
Toaster	250-1250	0.3-1.56	0.3-1.56
Washing Machine	500-3000	0.63-3.75	2.52-15
Welder 140A	5000	6.25	8 min

Please Note:

Inductive loads (typically electric motors, electric pumps, electric compressors and air conditioners) require 6-8 times more current to start than to run. Most generators can provide 100% overload for start up purposes. A 1 Hp electric motor therefore will require 3-4kVA for start up. Once the 1 Hp electric motor has started, it will only consume 1 kVA leaving a extra 2-3kVA available for other appliances.

However, the newer 'Inverter' style generators may be more efficient and capable of starting higher loads.

Generator Selection

The generator size must be equal or greater than the total consumption of all applications. The higher starting requirement must be taken into account accordingly. To maximise the generator potential, the largest electrical motor should be started on its own and further appliances should only be switched on thereafter.

Why Choose Us?

You come first

You’re important to us and we want you to know it! Our goal is to keep you satisfied with first class customer service, high quality products, and extras you won’t find elsewhere. Our pre-delivery service and load testing mean that you will be ready to use your generator straight away.

History

Macfarlane Generators have over 75 years of experience. From humble beginnings in Melbourne, we have since expanded into Sydney, Brisbane and Perth. We are a trusted generator specialist, which is why we’ve been around so long and will continue into the future!

Aussie Locals

We're a 100% Australian owned and operated company. When you do business with us, you're supporting the Australian economy, and Australian workers.

Melbourne	136 Fairbank Road, Clayton South VIC 3169
Sydney	1 St James Place, Seven Hills NSW 2147
Brisbane	31 South Pine Road, Brendale QLD 4500
Perth	1/85 Dixon Road, Rockingham, WA 6168