We'd like to help you with some of the most commonly asked questions. If you have other things you would like to discuss, feel free to contact us so that we can help you make an informed decision about purchasing a generator.

You need to consider:

  • What is the generators wattage capacity and will it support your needs?
  • Does the generator have enough outlets to plug in all of the items i want to power?
  • How noisy is the generator?
  • Do you prefer a recoil or an electric start generator?
  • Do you prefer a diesel or a petrol powered generator?
  • How large is the fuel tank and how many hours of operation will it provide?
  • Can the generator be easily transported?
  • What accessories will you need to run the generator?

If you are unsure about any of the above, simply give us call and we will gladly assist you!

It is very important to choose the right sized generator for your needs. If you choose a generator that is too small, you will not be able to run your essential appliances during a power outage. Further, overloading the generator may lead to its breakdown as well as damage to all appliances that are using its power. 

 
On the other hand, if you choose a generator that is too big, you will be spending more on its purchase, installation, fuel, maintenance and repairs than required. Choosing a generator that is too big may lead to a huge and unnecessary initial cost.
 
The size of your generator depends on the number and type of electrical appliances that you plan to run. Heating and cooling appliances like air conditioners and refrigerators consume a lot of power. You will need a bigger generator to power such appliances. On the other hand, if you want your house to power lights, you can opt for a smaller generator.
 
Furthermore, appliances that have moving parts like fans and pumps consume a lot of electricity at start-up but do not require a lot of power to continue functioning. When electric motors form part of your appliances, you will need to multiply three times the motor horsepower (hp) to your required steady state load.
 

The first thing you need to do is work out your Total Electrical Load, using the power chart below. Then, you will need to establish your steady state load, such as lights and appliances, which you expect to operate at any one time.

APPLIANCE WATTS     APPLIANCE WATTS
Clothes Dryer 2,400 Television Set 75 - 200
Hot Water Service 2,500 - 3,000 Toaster 250 - 1,250
Iron 900 - 1,200 Washing Machine 500 - 3,000
Kettle / Jug 800 - 1500 Air Conditioner (Non-inverter) 1,000 - 2,500
Lights 25 - 200 Domestic Water Pump See Electric
Motor below
Radio 60 Electric Motor
0.25 hp*
0.5 hp*
1 hp*
2 hp*
187
375
750
1,500
Radiator 1,000 - 2,500 Welder, 140 Amp(Non-inverter) 5,000
Refrigerator 100 - 800 9"Angle Grinder 2,300

Above chart is a guide only and some appliances will vary their watts depending on brand.

QUICK CONVERSIONS

To convert Watts to kVA @ 0.8pf, divide Watts by 0.8.

Example: 

2000 Watts = 2.5 kVA
4800 Watts = 6 kVA
 

To convert kVA to kW @ 0.8 pf, multiply kVA x 0.8

CHOOSING A GENERATOR

1800 WATTS

Power tools rated up to 1000 watts. Portable Drill, Jigsaw, Toaster, Frypan, Lighting, Heating, TV, Small Fridge, ¼  to ½ hp Motor (depending on type). Ideal for the “Home Handyman”. Light in weight to power small appliances and for home use. Choose 2.4 kVA.

3500 WATTS

Power tools rated up to 2200 watts. Small Air Conditioner or Radial Saw, Lighting, Heating, TV, Microwave, Oven or Hotplate, Small Submersible Pump, ¾ hp Motor (depending on type). Choose 4.4 kVA.

6000 WATTS

Power tools rated up to 3400 watts. Small Air Conditioner, Radial Saw, Lighting, Heating, TV, Microwave, Oven or Hotplate, Submersible Pump, ¾ to 1 hp motor (depending on type). Choose 7 kVA. 

All information above is an approximation only.

As a rule portable generators should never be overloaded, however all Gentech portable petrol sets can provide twice their normal output for a short period (e.g. during start-ups).  

For example, a 4.4 kVA Gentech generator can deliver up to 3500 running Watts and 7000 starting Watts.

Important to note: If a generator is running for long periods of time with an overload (i.e. that is a rating above the maximum rating of the set) there are various things that may occur:

  • Overheating of the engine
  • Overheating of the alternator, which will burn out the windings.
  • Breakdown in oil consistency causing low oil pressure and engine failure.
  • Reduced generator lifespan.