Standby Generators

Standby Generators
This time of year many people are interested in a generator for home standby during the winter months. Below are a few suggestionsto help you make your decision on what type to use.

Petrol or Diesel?
Generally I would recommend a diesel generator for home standby, for the simple reason that diesel is a more stable fuel for long term storage. Petrol generators, if left for long periods of time can become difficult to start, as the petrol can turn to gel in the carburettor, this would then require the carburettor to be dismantled and cleaned. Also, if stored in cans in the garage for any length of time, petrol can deteriorate. Another point, diesel stored in cans is less of a fire hazzard than petrol.

Diesel generators are normally noisier than petrol, so it may be worth considering the fully enclosed silenced type of diesel generator.

How do I connect my standby generator to my house?
The best way to do this is to fit a mains /generator changeover switch. This will cost around £100 to £150 and will have to be installed by your local electrician. Once the mains changeover switch is installed, in the event of a power cut, you just connect your diesel generator to the external wall socket, start the generator, flick the changeover switch and you will have your normal electric supply to the house resumed, albeit, powered by your standby generator.

Be careful not to overload the generator. A standard residential mains supply is 100 amps, which equates to 23kw. It is not necessary to have a generator anywhere near this size, typically, an average home can manage quite easily with a 5kw generator, however, if you carried on using electricity as normal, you probably would overload a 5kw generator. There are two options, either be careful not to overload the generator, by only using the essential appliances, i.e. lighting, fridge, freezer, TV, PC, central heating pump etc. or the changeover switch can be wired to feed an essential use distribution board, where, when all the appliances connected to this board are switched on, it does not exceed 5kw. The second option, is the prefered method, but would require a little more work from the electrician.

Routine maintenance
Generally a standby generator does not require much maintenance, as it is rarely used.
It is very important to make sure the battery is in good condition and fully charged at all times. It is a good idea to run the generator for a couple of hours every month to make sure the battery is being kept charged, with the generator running, the battery voltage should be reading around 13-13.8v. Or use a small car battery charger once a month to keep the battery charged.
The engine oil should be changed every 100 hours or annually, whichever comes sooner for a 5 kw diesel generator.
The air filter should be changed every 500 hours
The diesel filter should be changed every 500 hours.
When you are testing the generator, check the voltage and frequency (hertz) readings. The volts should read 230v+- 5v. The frequency, which is a measurement of engine/alternator speed, should be set at 51.5hz, with no load.

The location of the generator is also very important. The exhaust outlet must be in the open air. All generators produce a lot of heat, this heat must be removed from the area immediately around the generator to prevent over heating. The generator must also be protected from the rain.

WARNING - Petrol generators produce carbon monoxide - this is an odourless gas that will kill you in minutes. DO NOT operate a petrol generator in an enclosed, or poorly ventillated area, or near open windows.

Well proven and recommended generators include the Hyundai DHY6000SE and the Evopower HD6000SL, these are both 5kw diesel generators that are popular for home standby use.
Visit: www.genpoweruk.co.uk or www.hyundai-generators.co.uk for more information.