If the OP has a socket in the house, not connected to the rest of his installation, into which he plugs the boiler when running off the genny then he doesn't need a changeover switch and he can't backfeed the grid.
Power cuts & Generators.
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What I am suggesting is no more than a complicated extension lead.
Also I would be unplugging the boiler/pump from the mains and plugging it into that extension lead. The outdoor connection would be of the correct type, I am not quite that daft
However I am now looking at going down the route of the inverter. Getting a large caravan type battery and then running the boiler/pump via the inverter off of that. £200 for the inverter and another £150/£200 for a battery should do. Again I would be removing the permenant fixture wiring and replacing it with a plug and socket. So power goes off. Connect battery. Unplug boiler/pump from mains and plug into inverter. How does that sound? What rating/power/amps/watts of inverter should I buy?
Enjoying he feedback by the way. Was also thinking of sitting by a socket with my fingers stuck in it so I know when the power comes back on..
My apologies. But you'd be amazed how many people are, and really do plug the supply from a generator into a socket with a widowmaker.The outdoor connection would be of the correct type, I am not quite that daft
Sounds fine - check on the car forum, or a caravanning one, for tips on battery management.
Check with the boiler specs, but probably only a few '00W. Unless you've got motorised valves....
You do need to talk to Worcester Bosch anyway to find out whether you need a true sine wave inverter, and you need to make it clear to the inverter people that you want one that can handle an inductive load like a pump and run continually - ask eric to point you at his tale of woes concerning an inverter which would not run continually. And of the problems buying one from a non-UK supplier.
Don't be daft man - that would be ridiculous.Enjoying he feedback by the way. Was also thinking of sitting by a socket with my fingers stuck in it so I know when the power comes back on..
You don't want to have to be stuck in one place like that - you need to be able to move about. Get a long piece of flex, put a plug on one end, bare the L&N at the other end, spread the conductors apart and stuff it down your trolleys.
Thanks for that. Just sent off an email to Worcester Bosch should get a reply tomorrow.
Right off to have a bath now. Should be nice and warm in there just stuck the electric fire on the edge of the bath to take off the chill.
Right off to have a bath now. Should be nice and warm in there just stuck the electric fire on the edge of the bath to take off the chill.
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Last year I made a 'box' for a neighbour. Because they use a wood burning stove and boiler there was a worry if the power failed just after refueling.
The box is basically a few relays and connections to an inverter which itself is linked to a car battery. Power from the controller and the main power supply enter the box. If mains power fails the inverter fires and powers the pump ONLY (the supply is disengaged). This has worked well through a number of supply failures and cost about £40 including the solar panel which keeps the battery topped-up.
The box is basically a few relays and connections to an inverter which itself is linked to a car battery. Power from the controller and the main power supply enter the box. If mains power fails the inverter fires and powers the pump ONLY (the supply is disengaged). This has worked well through a number of supply failures and cost about £40 including the solar panel which keeps the battery topped-up.
Sounds just what I am looking for.
T
tonyelectric
I'll be interested to see what Worcester say, I would be suprised if you can run an oil boiler for long if at all from a battery/inverter set up (unless of pretty high capacity) as most oil boilers are pressure jet and have a motor to drive a fan and oil pump, an HT transformer to keep the thing alight and at least 1 solenoid valve, add to that the circulating pump and any motorised valves...
When I was growing up in darkest Herefordshire, we had a bit of kit called a Lister Start-O-matic, basically when the power went off a contactor started the generator and switched the tails over to the genny with a monitor wire bridging the switch with a large resistor to "sense" when the mains came back up and reverse the sequence.
Now ours was 30 years old then, but surely something is still made, R.A.Lister became Lister-Petter and I think are still trading in Dursley Glos. , the control box itself was made by MEM but branded Lister
When I was growing up in darkest Herefordshire, we had a bit of kit called a Lister Start-O-matic, basically when the power went off a contactor started the generator and switched the tails over to the genny with a monitor wire bridging the switch with a large resistor to "sense" when the mains came back up and reverse the sequence.
Now ours was 30 years old then, but surely something is still made, R.A.Lister became Lister-Petter and I think are still trading in Dursley Glos. , the control box itself was made by MEM but branded Lister
Our old factory emergency light genny was a Lister. Never let us down in over 40 years. Lister are still trading in Dursley although there was a rumour that they were moving up by us (Tewkesbury) but I think that's fallen through.
Another option would be to install a dedicated generator backed DB like this one which is quite simple to install.
In short it's mounted next to the CU and the circuits that need generator backing are transfered from the CU into this small distribution board. The various circuit MCB's are under the cover.
The DB is fed from the CU via a single suitably rated breaker, depending on what and how many circuits have been transfered. In your case you could transfer the heating and maybe the ground floor lighting. You could also add a socket fed from this board so that during a long power cut you could power other things, subject to the generator output.
This is a very simple way of using a small generator to back a few essential circuits without breaking into the tails. You can also forget about load shedding because you only transfer circuits that you generator can support
In short it's mounted next to the CU and the circuits that need generator backing are transfered from the CU into this small distribution board. The various circuit MCB's are under the cover.
The DB is fed from the CU via a single suitably rated breaker, depending on what and how many circuits have been transfered. In your case you could transfer the heating and maybe the ground floor lighting. You could also add a socket fed from this board so that during a long power cut you could power other things, subject to the generator output.
This is a very simple way of using a small generator to back a few essential circuits without breaking into the tails. You can also forget about load shedding because you only transfer circuits that you generator can support
Automatic generator starters and transfer switches are common in commercial/industrial environments, but (IMO) pointless overkill for a house. More expense and more complexity to solve a problem you don't really have, i.e. it being a real problem to have no power until you've done a manual start and a manual changeover.
Lister?
A good claim to being the finest diesel engine makers ever, and generators using them are often bulletproof.
So they are likely to be scarce and expensive on the 2nd hand market. A handy feature of older diesels is that they are lower tech, and tolerant of or easy to adapt to run on different fuels - if you've got a tank of heating oil you've also got a tank of fuel for your generator.
[EDIT]Spleling misteak corretced[/EDIT]
Lister?
A good claim to being the finest diesel engine makers ever, and generators using them are often bulletproof.
So they are likely to be scarce and expensive on the 2nd hand market. A handy feature of older diesels is that they are lower tech, and tolerant of or easy to adapt to run on different fuels - if you've got a tank of heating oil you've also got a tank of fuel for your generator.
[EDIT]Spleling misteak corretced[/EDIT]
Or if you don't mind doing that....
Not shown is the isolator before the henley block, which makes breaking into the tails an awful lot less fraught, and it assumes a C/O switch rated at 60/80/100A - whatever the supply is.
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There are two types of inverter the sine wave and the modified sine wave. The 150W inverter for sine wave costs around £170 where a modified sine wave costs around £40 from same supplier. With the smaller models like 150W it is likely you can pick them up a lot cheaper the links are to a Ships supplier and tend to be expensive.
From this you can see important to find if you need a sine wave or if a modified sine wave will do. Need to ask manufacture of central heating.
However I will warn you about the cheap inverters from china. I bought one a 3000W model with 6000W peak with idea of running a washing machine. However the inverter went up in smoke the expensive blue stuff and although it was guaranteed I had to pay transport with an inverter costing £140 the transport cost was £80 to return for repair. Seems although rated at 3000W even a 2000W kettle was too much for it.
Learn from my mistake and buy from supplier in UK.
You can get combined inverter and charger again this is not cheapest but they do have a good name and I assume you only want to do it once.
Generators also of course come with different speck and the Wispergen is likely the best for silent generators but the cost is something else. As one goes down the scale the Inverter generator is a big step forward where it can vary in speed according to power required so cheaper to run. As the price goes down the noise goes up these will likely annoy the neighbours.
As to connecting up the old idea of two sockets and single plug one from mains the other from alternative source is the simple method. However earths are a problem. With a single item it is not too much of a problem like with bathroom shaver socket with no earth being saver than using full earth system and RCD. But once you start to add to the system then you must allow for two faults and so earth rods and RCD protection is a must. You can't use suppliers earth when there is a power cut the earth may also be cut.
Some generators have odd earthing arrangements and I would steer clear of duel voltages generators.
My central heating has a transformer to give 24v AC control circuit this will work OK from modified sine wave. The water pump also will run from a modified sine wave. But mine is a very simple system. As one moves to the more complicated systems then you may need true sine wave.
My sons central heating ran from 12vdc called eberspacher it was very small with high output
these are designed for marine and wagons and can be added to an existing system. Being designed for many fuels and able heat water like any other central heating boiler they work well however they do not comply with the energy saving requirements for a house. i.e. not condensing.
With so many options not an easy to choose. Glad to say since moving to this house power cuts are rare so no special requirements here.
From this you can see important to find if you need a sine wave or if a modified sine wave will do. Need to ask manufacture of central heating.
However I will warn you about the cheap inverters from china. I bought one a 3000W model with 6000W peak with idea of running a washing machine. However the inverter went up in smoke the expensive blue stuff and although it was guaranteed I had to pay transport with an inverter costing £140 the transport cost was £80 to return for repair. Seems although rated at 3000W even a 2000W kettle was too much for it.
Learn from my mistake and buy from supplier in UK.
You can get combined inverter and charger again this is not cheapest but they do have a good name and I assume you only want to do it once.
Generators also of course come with different speck and the Wispergen is likely the best for silent generators but the cost is something else. As one goes down the scale the Inverter generator is a big step forward where it can vary in speed according to power required so cheaper to run. As the price goes down the noise goes up these will likely annoy the neighbours.
As to connecting up the old idea of two sockets and single plug one from mains the other from alternative source is the simple method. However earths are a problem. With a single item it is not too much of a problem like with bathroom shaver socket with no earth being saver than using full earth system and RCD. But once you start to add to the system then you must allow for two faults and so earth rods and RCD protection is a must. You can't use suppliers earth when there is a power cut the earth may also be cut.
Some generators have odd earthing arrangements and I would steer clear of duel voltages generators.
My central heating has a transformer to give 24v AC control circuit this will work OK from modified sine wave. The water pump also will run from a modified sine wave. But mine is a very simple system. As one moves to the more complicated systems then you may need true sine wave.
My sons central heating ran from 12vdc called eberspacher it was very small with high output
With so many options not an easy to choose. Glad to say since moving to this house power cuts are rare so no special requirements here.
In your last post you mentioned "overkill". Although there is no problem whatsoever with your diagram why would you want to install a 60 or a 100amp change over switch at the origin and the associated cabling if you've only got a 2kVA generator. Seems overkill if the OP only wants to back a few hundred watts of lighting and maybe a 1kW of boiler and pump?
And just like your diagram, most domestic properties are also missing the isolator before the Henley block
Ah - Stirling engines - wonderful things.
Get one of these and the neighbours will love you
This is a stonking bargain in £/w terms, but you'd have to find a way to borrow the DNO's local substation, which could be a bit tricky.
110V as well as 230V is extremely common, as that opens up the site market, so avoiding those does limit your choice a great deal.
Some of the larger ones often have dual socket outlets, e.g. a 7kW model will turn out to have 2 x 16A outlets, and I've often wondered if they'd be in phase and could be commoned.
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You wouldn't, but the last time I posted that diagram to illustrate switching and earthing some smart a**e said "that's wrong, you can't have the 60/80/100A supply going directly into the C/O switch", and I wriggled out of that one by saying "of course you can if the switch is rated at 60/80/100A".
And anyway: http://cgi.ebay.co.uk/125-Amp-Gener...946?pt=UK_Garden_Lighting&hash=item45f73005a2
Well yes, but that's not too hard to sort out as long as your meter has an integral isolator, which a lot of modern Ampys do. Yeah - I know they're only SP, and therefore yada yada.... but a one-off to fit a DP isolator is no less safe than pulling the SP fuse.And just like your diagram, most domestic properties are also missing the isolator before the Henley block
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