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#143754 - 08/30/05 08:39 AM gen sets/domestic use
britspark Offline
Registered: 05/28/05
Posts: 54
Loc: southampton united kingdom
i have just come back to the office after being called to a property in the country side that has a propane fired generator.
there appears to be no tranfer switch and the set looks in really bad condition, IE, the hose clamps for the gas connection are a bit corroded and the hose looks a bit bulging in places, i have disconnected the outgoing single phase SWA and the gas bottle.

now here comes the problem,
the new owners of the property want a gen set (as the power cuts are numerous) but it not my feild of expertise,

load required;
lighting = approx 6 amp, lower floor only
power = approx 20 amp 2 x double outlets

any ideas on transfer switch and dis board arrangements??

gen set, gas, diesel or petrol, ?
autostarter or manual,?

all help would be greatful as this client spends over 100k with us over the year.

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#143755 - 08/30/05 04:34 PM Re: gen sets/domestic use
aland Offline
Registered: 05/20/04
Posts: 186
Loc: United Kingdom
Britspark, I havent had a great deal of experience with geny's and domestic installations; did get involved with chicken farms a good few years back had some monster geny's on them for standby power. Found Merlin Gerin (group Schnider) technical reps very helpful. Give them a shout, feel sure they will point you in the right direction.
#143756 - 08/31/05 02:28 PM Re: gen sets/domestic use
gideonr Offline
Registered: 12/18/04
Posts: 161
Loc: Edinburgh, Scotland, UK
Someone local to here has only a diesel genset as getting mains is beyond his (artist) means. His is a slow chugger, but still quite noisey, and he finds it difficult to start sometimes so wants an electric starter.

You need to overrate gensets a fair bit, especially if they're going to be feeding a varying load, as the speed governor can interact with the load swings.

If it's a non diesel then gas is better than petrol, cleaner burning and the motor lasts longer.

Had lots of blackouts here, sometimes for 5 days, but no genset as an old anthracite aga for cooking and hot water, and a UPS for the computer do the trick.
#143757 - 09/02/05 12:40 AM Re: gen sets/domestic use
Trumpy Offline

Registered: 07/05/02
Posts: 8211
Loc: SI,New Zealand
Not sure what the fuel prices are like in your neck of the woods, but if they are anything like here, this could make for a tough choice.
I would go with either Diesel or Propane.
The Transfer switch will be the most expensive item and the hardest to install.
Provided that the Genset gives 240VAC output you will be OK.
I'd get in contact with the Power company before you do anything though, they will have rules regarding inter-connecting with thier system to make sure that there is no way that a Back-feed can happen.
Manual start is the simplest and to a degree the safer option,as if there is a remote start switch, you have to have a padlock-able switch on the Genset itself, that prevents the Genset from starting while it is being worked upon, unless the remote switch can be locked out.
I agree with Alan though, Tech Reps are your best source of info/help.
Often these guys are not salesmen, but ex-Electricians that sought to move into that side of the field.
We have an ABB rep here and he is a gold-mine of information, you don't get a sales pitch either, just knowledgeable help.
You just have to ask.
Let's face it, these days if you're not young, you're old - Red Green grin
#143758 - 09/04/05 09:51 AM Re: gen sets/domestic use
TeesdaleSparkUK Offline
Registered: 09/04/05
Posts: 20
Loc: England
The simplest way to do it is to use a changeover switch with one side on the mains and the other side on a 32A surface mounted plug. Get a portable generator and a lead with one trailing socket outlet and one plug to connect to the generator when needed.

You need to provide an earth rod to comply with BS7671.

[This message has been edited by TeesdaleSparkUK (edited 09-05-2005).]
#143759 - 09/04/05 03:30 PM Re: gen sets/domestic use
Texas_Ranger Offline
Registered: 12/17/01
Posts: 2391
Loc: Vienna, Austria
I'm afraid that's not exactly the correct way to do it... I doubt you'd find a gen set with a plug on it, exposing live pins while the set is running!
Basically you need a standard 32A extension cord with plug and trailing socket. Plug goes into the generator, trailing socket connects to the wall-mount socket.

Friends of mine have such a setup, transfer switch in the main panel, plug in the garage (I think 16A red CEE) and a short extension cord. 3ph generator that is powered by the tractor. Whenever there's a power outage they just switch over and fire up the generator.
#143760 - 09/04/05 03:54 PM Re: gen sets/domestic use
Alan Belson Offline
Registered: 03/23/05
Posts: 1803
Loc: Mayenne N. France
Um... I don't want to throw a spanner in the works but... if your client is hoping to run the fridge/freezer off that gen set, beware. My experience, in the long power cuts of the seventies, is that you need a thumping big set to start the motors of quite small refrigeration appliances- big enough in fact to run the whole house as normal. Wiring up to only run a couple of outlets and downstairs-lights adds complication to the transfer switching too, doesn't it?

Wood work but can't!
#143761 - 09/05/05 03:32 AM Re: gen sets/domestic use
pauluk Offline
Registered: 08/11/01
Posts: 7520
Loc: Norfolk, England
The compressor motors on fridges can take a surprisingly high surge current when they start up.

Out here in the sticks it's not at all unusual to see a quite-noticeable momentary dimming of the lights as a compressor kicks in.
#143762 - 09/05/05 03:39 AM Re: gen sets/domestic use
britspark Offline
Registered: 05/28/05
Posts: 54
Loc: southampton united kingdom
thanks for all of your replies,

the client has had a bit of a rethink, after also talking to the local PoCo, (Scotish & Southern Power)they are going, within the next year, replay and upgrade all the main power lines to the area,

i was looking forward to actually fitting the building out but the cost was alittle to steep, i had a basic quote, just for the GenSet of over £6000.00, thats a Propane one!

add all the rest of the kit and the job was looking about £10,000.

so the client is going to put up with the outages and wait.

but one thing he has had supplied by us is a decent size UPS and an extra heavy duty 12v power supply for his intruder / fire alarm.

so all was not lost!!


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