Home backup generator connection.

[user 34453]

Hi all. Newbie here, just a home owner, not trained or qualified...so please be gentle!

I live in rural Aberdeenshire, Scotland where the views are stunning but the broadband is rubbish and the wiggly-amps supply more sketchy than they should really be for a first world country.

Anyhoose...storm Arwen wandered through the other day and took us off supply for five days. It's the third time in about ten years we've had a four/five day loss of supply and in any given winter we often loose the supply for multiple hours due to snow and/or ice. So, I'm thinking about a back-up generator connection for the house.

I am thinking of using a manual transfer switch as I don't need the security or complexity of an automatic system. The whole affair would, of course, be installed by a qualified electrician. I will only need to supply a few consumers such as the two heating circulation pumps and associated control gear, some lights and some sockets for charging phones etc. I have a gas hob for cooking so no big consumer there.

So, my three questions are:

1. Is an inverter generator necessary to protect my 'sensitive equipment'? This is the way they are advertised but I thought that modern charging power supplies were pretty good at accepting variable inputs to produce their 5V. Someone else said that the fridge was pretty sensitive. Is that true?

2. A friend has the same setup installed a few years ago but the sparky would not connect the whole Consumer Unit citing that the house load was far too great for the generator. He installed another smaller CU with only two circuits for one lights and one ring. I haven't asked anyone to look at my job yet but why wouldn't I be able to connect the whole CU and be trusted to limit my consumers, especially as modern generators appear to have such good overload protection.

3. What about the earth question? Do I need a separate earth for the generator? There seem to be a lot of discussion just on this topic alone.

Looking forward to your replies.

Cheers,

Jack

 

[Andy™]

1: maybe. maybe not. decent generaotors with AVR will be fine, however these usually run constant speed regardless of load. inverters can vary speed depending on load, so if youre not using much powerm quieter since its running slower

2: nothing wrong with keeping existing and using a changeover switch, but youll need to remember to turn off some higher power loads i.e shower etc. worst case itll overload the generator and trip it. not ideal, but its not likely to do any damage so not really an issue worthy of splitting boards just for that

3: yes. generator will need an earth electrode. usually would be run as a TNS system but some generators (smaller ones) often run as IT though

 

[Richard-the-Ninth]

I would suggest a 2nd consumers unit and circuits would be better, human nature means you take the easiest option, so you would have to "run round" isolating things you can not use (You would soon get fed up, or easily miss something.) It would be better to have "standby lights installed, and one or two standby sockets (All powered by your generator) It would be better and more cost effective in the long run, also, if you leave an existing light switched on, when the mains is restored you would instantly know as the light would come on.