After Eskom blackouts, generator risks
As soon as the lights go out, the generator is started – but what are the hazards? Leighton Bennett, vice chairman of the Safety First Association, shines some light on the matter.
Generators do not have earth leakage protection like those installed on the electrical distribution panels/boards in buildings. Earth leakage protection can be added, however, by using an earth leakage device, depending on where the generator power supply is connected to the electrical distribution board.
Earth leakage protection is strongly advised as generator electricity is unlikely to trip should one get an electric shock … This shock risk is also increased if the generator is not earthed by not being connected to an earth spike driven into the ground.
For safety reasons, have an earth leakage protection device fitted into an extension box, which is made for your generator, and connect all extension leads from this earth leakage box, and not directly from the generator. This box will trip the electricity if there is any electrical shock or short to an earth.
Make the right choice
Every generator has a maximum output capacity. If it is plugged into a house system where the power demand could be exceeded, it could blow the generator’s electronics. It is, thus, important to calculate your maximum demand. Add up the wattages marked on all the electrical appliances and fixtures that would require generator power. Your generator will need to have output wattage that is greater than your total demand wattage.
Use the formula “Watts = Amps x Volts” to calculate the required capacity or size of the generator you would need to acquire as your emergency power source.
Obviously, you would not be able to use high power demand items like geysers, stoves, ovens and appliances like kettles or irons, which require significant watts to operate. Fridges, freezers, security and gate access systems, computers, the TV and some light lamps, with energy-saving globes, can all be run off a medium-sized generator, however.
Putting it all together – correctly
To connect your generator to your existing electrical board, a proper turnover isolation switch must be fitted, by a competent electrical person, to safely separate between the two power supply systems.
If the building power supply is not properly isolated with a turnover switch, between the generator and the building system, the generator will be destroyed when the normal power supply returns.
If an isolation switch is not used, one can use specific, separate, permanent extension leads fitted from the generator location to emergency power plug points in the desired locations in the building or house. When the generator is running, you just have to unplug the item from the normal plug and connect it to the generator plug point and reverse the process when the normal power supply returns.
Some generators are being plugged into the house/office wall plug using an extension lead fitted with a double male electrical plug, however … This is hazardous as the plug pins could be live if the extension is plugged into a running generator. Such a practice is illegal in terms of the electrical wiring codes and will be considered gross negligence should a fatality occur.
The lights might be out, but the danger is still there …
It is essential that all electrical plug points and electrical appliances, such as stoves and irons, are treated as being “ON” to avoid injury.