11-04-2022 5:19pmRegistered Users Posts: 6,140 ✭✭✭Join Date:Posts: 5942
Does anyone have any advice on generators, I'm looking for something in the 5 -7 Kw area suitable for use as emergency back up power for a house....I know it wouldn't be able to run a power shower etc but enough for light(s), tv fridge sort of job
I'm seeing a lot of good looking welder ones with good quality honda engines on them (GX) good alternators but they seem like they are for work on a site.......tanks have about 2 hour runtime on them and no built in Automatic Voltage Regulator.........can these be adapted to use as emergency backup or is it not worth it? so many things have chips or digital displays on them now I presume they would be fried without an AVR if hooked up to these welder type generators?
So can you add an AVR or does it need to be wired to motor to throttle it up and down as demand fluctuates and if the tank only has about 2hrs worth of fuel is it unwise to keep them on the go for much longer etc.
The ones built for purpose dont seem to have a decent engine on them or if it is Honda you are talking 4/5k for the required output.....its hard to know if some of the brand names are using Loncin engines or not...and if they are are these honda copies and nearly as good in terms of parts availability/servicing etc0
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I looked at this before as I worked with large gas engine CHP's at the time.
The power supply is so consistent across most of Ireland, with the exception or very isolated coastal regions, that the cost will outweigh the few hours power outtage suffered each year.
An AVR is essential for any modern household appliances.
The AVR alters the excitation voltage (to stabilse output voltage) as opposed to the RPM, the RPM must be constant.
(I don't know if an AVR can be retrofitted)
Do you have a change over switch on the 16mm incomer feed? AFAIK It's a legal requirement to prevent back feeding the grid. (Although a generator can back feed a dwelling through a socket, (with the inccomer fuse removed) its not the safest
I binned this idea after getting advice at the time, as the cost would outweigh the benefit for a few hours outtage every year.0
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I'd normally agree with that but Europe could be looking at power generation shortfalls over the next couple of winters we could all be looking at generators yet. Although a few batteries and an inverter might be just as useful in that scenario to keep a critical appliances and the heating circulating pump running.0
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Im thinking of running a lead from the generator into the house and plug the few critical appliances into it. I know ill have to research what sort of cable will be required to handle the current draw and it cant be too long etc ......a manual transfer switch is in the long term plans.......no way I'm trying to feed the entire house and risk electrocuting myself or some unsuspecting esb worker
Normally Id agree with you re not bothering buying it but I can find uses for it off farm re: welding (im slowly building bits and pieces on an offfarm and I might need it for a few jobs requiring a pump as well + I have a deep freeze might need back up power.......Ultimately you are probably correct but I've nearly convinced myself im getting one now as I reckon I have a couple more uses for it than the average householder...fools and their money eh?0
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We have a generator attached to house in same way as Fintan described - i.e. backfeeding in from a socket, but isolating from grid at the consumer unit. It's a PITA as mum and others are too scared to set it up.
If there are others in the house then I'd make a point of having it that anyone can get it going. So, ignition start and a transfer switch. Leave the generator with a trickle charger across the battery to keep it primed and ready for use.
Will you always have it stored beside the house? Ours are usually in the shed - so okay for a scheduled outage, but for random outages - which usually occur in awful weather, then who is going out to the shed for it and set it up when knowing that the power will be back on in an hour or two usually now. Back when I was younger the outages would be more frequent and longer duration, but now the grid is in better shape and the fault detection and repair a lot quicker.
We have been in house during outages and just sat on rather than go out and turn on the generator. If you are going to be pissing about plugging in here and isolating there and back to start the thing. Might be best at least getting a quote for doing the job right and then everyone can benefit - not only when you are about. Plus it will be installed to code and insurance should be fine.2
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You're into big money to get any sort of decent setup.
Here's the cheap way.
I had a changeover isolator put in when I built the house and I just plug into a 32 amp outdoor plug outside the door using a lead with a male connection.
I've used different generators with it. None were sold as rectified current which is what they say you need, but we've used computers, sky box, router, and TVs without damage so far.
Last outage in the storm, all I had was a 2000 watt Aldi suitcase genny which I was using for shearing last year.
It clearly wouldn't run the whole house so I just hit down the breakers on everything and added back with the door open and listening to the sound of the genny.
Lights TV etc all fine, hot press circulation pumps so that I can have the stove on and so have heat in the rads.
A few times a day I turned off almost everything and turned on the pressuring pump in the garage to fill the cisterns.
Gas hob here, ( 20 euro camping stove will do either). Freezer - don't open it and it'll be fine for 2 to 3 days. (You could give it the power for a few hours at night when asleep if necessary)
Fridge - its only small money anyway whats inside..
All this only works if I'm around myself to understand the systems and loading. Wife wouldn't be able to set it up.
Biggest problem I had last time is that I had almost no petrol and ended up tipping the chainsaws into it after their mix and some I borrowed from a neighbor in order to keep it going. (Local fuel stations had no power either and were closed)
We were warm and had tv/light for 12/15 hours out of about 10 litres of fuel approx.2