Choosing your generator

One has to decide what your priorities or needs are before any decisions can be made as to what to purchase.
When considering the above, remember that certain appliances use:

* Elements (geysers, kettles and heaters) and the wattage on the item is usually the correct value to use when adding up what wattage is needed from the generator.
* Electric motors to start up (the compressor in a fridge). The appliance may well state five amps, but this is usually running amps and not the amps needed to start the appliance. In the case of five amps being the running amps for the item, at least three to five times the current is drawn on start up (20-25 amps are drawn on start up). With the use of the following formula it can be established what size generator you will need.
* Add the watts on appliances you wish to run. For example, if the total is 5000 w, this equals 5 kVA. Times this by 1.2, which equals 6.5 kVA, (the size of the generator you will need). Very simply put 5 500 w is similar to 5.5 kVA at sea level.

Methods to install

* Automatic Mains Failure (AMF) with a UPS – has no delay before the power is restored. It switch off your normal power supply and your generator on, without you leaving your chair while watching your favourite TV programme.
* Manual Mains Failure (MMF) – will switch off your power supply and requires that you leave your chair and go to the generator to start it up.
* Manual change over panel – requires that you switch off your normal supply and start the generator yourself.
* Direct Method – This is the simplest method. The appliance is plugged into the generator directly via an extension cord. In this case, the only outlay is the cost of the generator.

Petrol vs. Diesel

* Petrol Pros
- Capital outlay is at least half that of the equivalent size
- Diesel generator, if this is a standby set it is a good proposition.

* Petrol Cons
- Highly flammable
- Fuel consumption is high

* Diesel Pros
- Maintenance costs less than Petrol
- If the set is used for 24 hours the engine will last a great deal longer than petrol
- Diesel is more fuel efficient
- Operating costs are less in the long run

* Diesel Cons
- Capital outlay is at least double or more than that of a petrol set

Choosing your supplier

A generator is an investment which, one hopes, like a fridge or a washing machine, you will not have to replace for years, (if ever). Make sure that you use a well known reliable brand. Be aware of copies which advertise similar outputs to the real thing. Remember you get what you pay for. Spares should be easily available and facilities for servicing should be available nationally.

Installation

* Use a local electrical contractor to do your installation. Try a number of contractors for quotes and advice to confirm that the price is reasonable.
* Check that the contractor is registered and qualified to work on the council’s network in your area.
* Remember that if the contractor installs the generator wrongly, the generator can burn out and no company will warrantee the product.

Tips and Hints

* Never refuel a petrol generator while the engine is running. A spark from the sparkplug can ignite the fuel and start a fire.
* Always make sure that the appliances or power tools are switched off before starting up the generator.
* Do not use an extension which is longer than 15m without increasing the diameter of the cable.
* Always refuel before the tank is empty (remember to switch off). Just before cutting out when running out of fuel, the alternator does not produce the correct voltage and could burn out your appliances & tools.


Tools - Generator Required
Battery Charger (10 Amp) 350 – 1000 Watts
Soldering Iron 350 – 1000 Watts
Electric Drill 350 – 1000 Watts
Jig Saw 1400 – 2500 Watts
Electric Mower 1400 – 2500 Watts
Router 1800 – 2500 Watts
Grinder 1800 – 2500 Watts

Domestic Appliances - Generator Required
Television 100 – 500 Watts
Toaster 1000 – 1750 Watts
Vacuum Cleaner 1000 – 2500 Watts
Refrigerator 1000 – 2500 Watts
Microwave 1000 – 2500 Watts
Hair Dryer 1000 – 2000 Watts
Washing Machine 1800 – 3500 Watts