Nigel M wrote:

I want to set up a 12v lighting system in a outbuilding, possibly with a
12v battery to be topped up by a solar cell. The system will need to
provide light for a 4m x 4m room, for an hour or so a day.

Anybody got any suggestions?

What level of light is required? Just enough to read by? Enough to do
detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but nowhere
near enough for say a workshop.


--
Grunff

Nigel M brought next idea :
I want to set up a 12v lighting system in a outbuilding, possibly with a
12v battery to be topped up by a solar cell. The system will need to
provide light for a 4m x 4m room, for an hour or so a day.

It really depends upon how much light you might need. You can buy 12v
light fittings as used in caravans and for camping, these are fairly
efficient consuming 8 to 12watts each. Alternatively you might consider
the 12v quartz lights with built in reflector, which are normally run
from a transformer in domestic situation. These can be obtained in
20watt and 50watt versions.

Obviously the higher the wattage used, the larger the battery would
need to be and the solar cell to recharge it. In addition you might
need a control on the charging system. For what an adequate solar cell
and battery would cost, you might find that running a mains supply
would be the cheaper option.

--


--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

"Nigel M" wrote in message
...
In uk.d-i-y, Grunff wrote:

What level of light is required? Just enough to read by? Enough to do
detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but nowhere
near enough for say a workshop.

Sorry, I should have said. This is a stable, so enough to see the horse!
I was thinking of around 40W of tungsten, so I think an 8W fluorescent
tube would be ideal.

But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Halfords. Or any other similar car place. Together with a motorcycle
battery and a small charger.

Nigel M wrote:

Sorry, I should have said. This is a stable, so enough to see the horse!
I was thinking of around 40W of tungsten, so I think an 8W fluorescent
tube would be ideal.

All our stables have a pair of 13W CFs each. This is plenty.

Don't use tungsten - waste of energy.


But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Ok, you need a light, like this:
http://maplin.co.uk/Module.aspx?ModuleNo=22907&TabID=1&source=15&World ID=&doy=13m10

Then you need a car battery. They are well suited to this type of
application, where they don't get fully discharged. Local scrap yard is
a good place for second hand ones (£5 each), or any motor factor.

Then you need a solar panel. A weatherproof one is a good idea, and if
it doesn't have a diode built in, you need to add one. Tjis one is ideal:

http://maplin.co.uk/Module.aspx?ModuleNo=2317&TabID=1&source=15&WorldI D=&doy=13m10


Then you need some cable and a suitable switch. I'll leave those for you
to figure out ;-)


--
Grunff

Nigel M presented the following explanation :
Sorry, I should have said. This is a stable, so enough to see the horse!
I was thinking of around 40W of tungsten, so I think an 8W fluorescent
tube would be ideal.

But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Any caravan or outdoors type of dealer would have the complete tube and
fitting for £10 to £15. They would also probably stock the type of
battery you need, a type intended for deep discharge rather than a car
type battery.

www.maplins.co.uk stock a range of solar cells. One of the smaller ones
intended to charge a 12v battery would easily cope with replenishing
8watts used for one hour.

Simply wire in twin flex (the smallest size of mains flex is adequete)
from the battery positive (+ve) via an in line fuse of 5amps to both
the + of the solar cell and one terminal of a switch. From the second
terminal of the switch to the + of the light. The negative (-ve) of the
battery needs to be connected to the -ve of the solar cell and the -ve
of the light.

Black = -ve, it is conventional to use the blue in the flex for this.
Red = +ve and it is convention to use the brown in the flex for this.

Almost any switch can be used, but probably a pull cord switch as used
in a bathroom might be best. Any DIY store would stock these, as would
the electrical wholesalers.

--


--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.org

On Wed, 13 Oct 2004 22:29:49 +0100, Harry Bloomfield wrote:

Nigel M brought next idea :
I want to set up a 12v lighting system in a outbuilding, possibly with a
12v battery to be topped up by a solar cell. The system will need to
provide light for a 4m x 4m room, for an hour or so a day.

It really depends upon how much light you might need. You can buy 12v
light fittings as used in caravans and for camping, these are fairly
efficient consuming 8 to 12watts each. Alternatively you might consider
the 12v quartz lights with built in reflector, which are normally run
from a transformer in domestic situation. These can be obtained in
20watt and 50watt versions.

Obviously the higher the wattage used, the larger the battery would
need to be and the solar cell to recharge it. In addition you might
need a control on the charging system. For what an adequate solar cell
and battery would cost, you might find that running a mains supply
would be the cheaper option.

--

Remember to vent the battery to the outside - you don't want a shed full of hydrogen.....

May be worth looking at one of those 'portable power' type devices, containing a battery and charger
that you occasionally see in cheapo shops, but remember that lead-acid batteries DO NOT like being
left flat for long, so you must remember to charge it regularly.
Solar would be ideal if you can get enough capacity at a sensible price. The sort of places that
supply to boatowneres would probably have everything you need, but at a price.
Surplus solar cells are sometimes findable cheaply.
Never forget ebay.co.uk as a possible source for this type of thing.....

In article ,
Harry Bloomfield wrote:
Any caravan or outdoors type of dealer would have the complete tube and
fitting for £10 to £15. They would also probably stock the type of
battery you need, a type intended for deep discharge rather than a car
type battery.

There's no need to get a deep discharge type for 8 watts for an hour. That
wouldn't even scratch the surface of the smallest car battery. If the
solar system works properly and keeps it topped up. I'd expect a car
battery to have a longer life under these conditions than those it's
designed for.

--
*Marathon runners with bad footwear suffer the agony of defeat.*

Dave Plowman London SW
To e-mail, change noise into sound.

"Nigel M" wrote in message
...
I want to set up a 12v lighting system in a outbuilding, possibly with a
12v battery to be topped up by a solar cell. The system will need to
provide light for a 4m x 4m room, for an hour or so a day.

Anybody got any suggestions?



I've done a similar thing in a rented council garage with no mains power. I
originally used 3x 50w 12v bulbs but these were pretty dim and drank power.
Current consumption was over 12 amps.

So, I swapped these out for cheap 20w CFL's (similar to 100w tungsten each
apparently) and used a cheap mains inverter from maplins to power them.
Result = far more light and far less power drain.
I modified the inverter to extend the on/off switch to an extrenal wall
mounted light switch. It's powered from a 65ah leisure battery and a solar
panel bought on ebay - can't remember power rating but about 1'x3' in size.
Panel is fitted to garage roof and system has been operational for over a
year so far with no problems. Inverter based lighting system has added
bounus of low current mains in garage for small tools or radio etc.

Alan.

Nigel M wrote:

In uk.d-i-y, Grunff wrote:


What level of light is required? Just enough to read by? Enough to do
detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but nowhere
near enough for say a workshop.


Sorry, I should have said. This is a stable, so enough to see the horse!
I was thinking of around 40W of tungsten, so I think an 8W fluorescent
tube would be ideal.

Fluorescent style camping lights are far and away the most efficient
thing to use.

But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Camping stores and caravan places.

Amps is only an amp at best, so cable is easy. normal T & E can cope
with that.

What size battery? Well a standard car battery is about 30-70Ah, so for
an hour a day you should get a month out of even a small one. Halfords?

Charging 0- well you could jump lead it from the tractor or whatever and
leave it running for an hour or two every month on tickover.

If it were me, I'd run an extension cable temporarily and leave it on
crappo charger overnight every week to be sure, or possibly get a
battery with handles or on a trolley and get two of them, and have one
on charge and one in use, and swap them every week or so.

I am sure on this sort of duty cycle solar panels woud work or
windmills, but the cost....

Nigel M wrote:

Thanks for all the ideas, here are a few more questions:

In uk.d-i-y, Harry Bloomfield wrote:

www.maplins.co.uk stock a range of solar cells. One of the smaller ones
intended to charge a 12v battery would easily cope with replenishing
8watts used for one hour.


I think I may have underestimated slightly. The unit from Maplin looks
ideal, and there are two stables. So assuming each 18W unit takes around
1.5 amps, then this is 3AH. I don't see how a, say, 120mA solar panel
could replenish this. Or have I misunderstood something?


Simply wire in twin flex (the smallest size of mains flex is adequete)


That's the answer I wanted, I didn't think cable was correct.


Almost any switch can be used, but probably a pull cord switch as used
in a bathroom might be best.


Surely there are normally only for use with AC. I would have thought
that a fluorescent lamp would present an inductive load to a DC source,
so wouldn't this mean I needed a special switch?




Not really, no.

In article ,
Alan wrote:
So, I swapped these out for cheap 20w CFL's (similar to 100w tungsten
each apparently) and used a cheap mains inverter from maplins to power
them.

That's an expensive and inefficient way to do it - unless you also make
use of the 230 volts generated for other purposes. 12 volt DC florries are
cheap and readily available.

--
*You can't have everything, where would you put it?

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Nigel M wrote:
Almost any switch can be used, but probably a pull cord switch as used
in a bathroom might be best.

Surely there are normally only for use with AC. I would have thought
that a fluorescent lamp would present an inductive load to a DC source,
so wouldn't this mean I needed a special switch?

They don't give a DC rating for this sort of switch purely because that
application would be so rare. But in general, most 230 volt AC switches
will happily work at the same current rating on 12 volts DC.

If you're really worried, you could use a 20 amp shower type. ;-)

--
*Do paediatricians play miniature golf on Wednesdays?

Dave Plowman London SW
To e-mail, change noise into sound.

Nigel M wrote:

This is a good idea, the other could power the electric fence once it
was charged. Much cheaper than solar power.


How far is the nearest mains? We have hundreds of metres of 12V cabling
(all done in very cheap T&E) supplying things like electric fencing.

--
Grunff

The Natural Philosopher wrote:
Nigel M wrote:

In uk.d-i-y, Grunff wrote:


What level of light is required? Just enough to read by? Enough to
do detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but
nowhere near enough for say a workshop.


Sorry, I should have said. This is a stable, so enough to see the
horse! I was thinking of around 40W of tungsten, so I think an 8W
fluorescent tube would be ideal.

Fluorescent style camping lights are far and away the most efficient
thing to use.

But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Camping stores and caravan places.

Amps is only an amp at best, so cable is easy. normal T & E can cope
with that.

What size battery? Well a standard car battery is about 30-70Ah, so
for an hour a day you should get a month out of even a small one.
Halfords?
Charging 0- well you could jump lead it from the tractor or whatever
and leave it running for an hour or two every month on tickover.

If it were me, I'd run an extension cable temporarily and leave it on
crappo charger overnight every week to be sure, or possibly get a
battery with handles or on a trolley and get two of them, and have one
on charge and one in use, and swap them every week or so.

I am sure on this sort of duty cycle solar panels woud work or
windmills, but the cost....

We've suddenly got a plague of reactive road warning signs popping up all
over the county. They are all on long poles with a windmill on the top and
solar panel just below. If the council are using this technology then it
must be at a price where it starts looking good for other uses as well,
presumably the stables would be in a position to get a good dollop of the
available wind and sun?

--
James...
www.jameshart.co.uk

James Hart wrote:

The Natural Philosopher wrote:

Nigel M wrote:


In uk.d-i-y, Grunff wrote:



What level of light is required? Just enough to read by? Enough to
do detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but
nowhere near enough for say a workshop.


Sorry, I should have said. This is a stable, so enough to see the
horse! I was thinking of around 40W of tungsten, so I think an 8W
fluorescent tube would be ideal.


Fluorescent style camping lights are far and away the most efficient
thing to use.


But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Camping stores and caravan places.

Amps is only an amp at best, so cable is easy. normal T & E can cope
with that.

What size battery? Well a standard car battery is about 30-70Ah, so
for an hour a day you should get a month out of even a small one.
Halfords?
Charging 0- well you could jump lead it from the tractor or whatever
and leave it running for an hour or two every month on tickover.

If it were me, I'd run an extension cable temporarily and leave it on
crappo charger overnight every week to be sure, or possibly get a
battery with handles or on a trolley and get two of them, and have one
on charge and one in use, and swap them every week or so.

I am sure on this sort of duty cycle solar panels woud work or
windmills, but the cost....


We've suddenly got a plague of reactive road warning signs popping up all
over the county. They are all on long poles with a windmill on the top and
solar panel just below. If the council are using this technology then it
must be at a price where it starts looking good for other uses as well,
presumably the stables would be in a position to get a good dollop of the
available wind and sun?


Better still, take the grab loader and grab load one of the ****ing
things on a dark night and install it in that tree shrouded bit of garden.

People Power!

The Natural Philosopher wrote:
James Hart wrote:

The Natural Philosopher wrote:

Nigel M wrote:


In uk.d-i-y, Grunff wrote:



What level of light is required? Just enough to read by? Enough to
do detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but
nowhere near enough for say a workshop.


Sorry, I should have said. This is a stable, so enough to see the
horse! I was thinking of around 40W of tungsten, so I think an 8W
fluorescent tube would be ideal.


Fluorescent style camping lights are far and away the most efficient
thing to use.


But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Camping stores and caravan places.

Amps is only an amp at best, so cable is easy. normal T & E can cope
with that.

What size battery? Well a standard car battery is about 30-70Ah, so
for an hour a day you should get a month out of even a small one.
Halfords?
Charging 0- well you could jump lead it from the tractor or whatever
and leave it running for an hour or two every month on tickover.

If it were me, I'd run an extension cable temporarily and leave it
on crappo charger overnight every week to be sure, or possibly get a
battery with handles or on a trolley and get two of them, and have
one on charge and one in use, and swap them every week or so.

I am sure on this sort of duty cycle solar panels woud work or
windmills, but the cost....


We've suddenly got a plague of reactive road warning signs popping
up all over the county. They are all on long poles with a windmill
on the top and solar panel just below. If the council are using this
technology then it must be at a price where it starts looking good
for other uses as well, presumably the stables would be in a
position to get a good dollop of the available wind and sun?


Better still, take the grab loader and grab load one of the ****ing
things on a dark night and install it in that tree shrouded bit of
garden.
People Power!

Oh it's not a speed camera, it's a "slow down, bend ahead" jobbie. They
could have spent the money on proper road safety methods but instead they've
put up a distraction right where you need to be concentrating on the road,
the bumps, the hidden bend and the 10 foot deep car-eating drains 6 inches
off the edge of the carriageway.

--
James...
www.jameshart.co.uk

On Thu, 14 Oct 2004 19:34:47 +0100, James Hart wrote:

They are all on long poles with a windmill on the top and solar
panel just below. If the council are using this technology then it
must be at a price where it starts looking good for other uses as
well, ...

Well that depends have you asked a 'lectric company for a a supply
recently? It doesn't come cheap, a company I know has just paid over
=A35k for one and they dug the 200m trench and laid the duct not the
power company.

A small boat type turbine will generate enough to keep a battery
topped up at the envisaged useage. Always asuming you are not in a
sheltered position...

--
Cheers
Dave. pam is missing e-mail

James Hart wrote:

The Natural Philosopher wrote:

James Hart wrote:


The Natural Philosopher wrote:


Nigel M wrote:



In uk.d-i-y, Grunff wrote:




What level of light is required? Just enough to read by? Enough to
do detailed work? This can make a huge difference.

An 8W 12V fluorescent tube will provide enough light to see, but
nowhere near enough for say a workshop.


Sorry, I should have said. This is a stable, so enough to see the
horse! I was thinking of around 40W of tungsten, so I think an 8W
fluorescent tube would be ideal.


Fluorescent style camping lights are far and away the most efficient
thing to use.



But where to get one to run from 12V, what size battery, how to
re-charge, and what sort of cable and switching?

Camping stores and caravan places.

Amps is only an amp at best, so cable is easy. normal T & E can cope
with that.

What size battery? Well a standard car battery is about 30-70Ah, so
for an hour a day you should get a month out of even a small one.
Halfords?
Charging 0- well you could jump lead it from the tractor or whatever
and leave it running for an hour or two every month on tickover.

If it were me, I'd run an extension cable temporarily and leave it
on crappo charger overnight every week to be sure, or possibly get a
battery with handles or on a trolley and get two of them, and have
one on charge and one in use, and swap them every week or so.

I am sure on this sort of duty cycle solar panels woud work or
windmills, but the cost....


We've suddenly got a plague of reactive road warning signs popping
up all over the county. They are all on long poles with a windmill
on the top and solar panel just below. If the council are using this
technology then it must be at a price where it starts looking good
for other uses as well, presumably the stables would be in a
position to get a good dollop of the available wind and sun?


Better still, take the grab loader and grab load one of the ****ing
things on a dark night and install it in that tree shrouded bit of
garden.
People Power!


Oh it's not a speed camera, it's a "slow down, bend ahead" jobbie. They
could have spent the money on proper road safety methods but instead they've
put up a distraction right where you need to be concentrating on the road,
the bumps, the hidden bend and the 10 foot deep car-eating drains 6 inches
off the edge of the carriageway.

I know. Lots of those round here.

Rip em out.

Seen a horrendous accident caused by a speed chicane being obscured to a
driver following another car.

The 1 ft high concrete kerb destroyed the front suspension and rolled
the car upside down. All under the speed limit of course.

"The Natural Philosopher" wrote
| I am sure on this sort of duty cycle solar panels woud work
| or windmills, but the cost....

Home-made savonious rotor from an old oil drum?

Owain

"James Hart" wrote
| I am sure on this sort of duty cycle solar panels woud work
| or windmills, but the cost....
| We've suddenly got a plague of reactive road warning signs
| popping up all over the county. They are all on long poles
| with a windmill on the top and solar panel just below.

How securely concreted in? ;-)

There are big photovoltaic panels on some railway signalling equipment too.

Owain

In article ,
The Natural Philosopher wrote:
Seen a horrendous accident caused by a speed chicane being obscured to a
driver following another car.

The 1 ft high concrete kerb destroyed the front suspension and rolled
the car upside down. All under the speed limit of course.

Perhaps it will teach him to be able to see the road ahead clearly at all
times. By keeping his distance, or whatever. If he didn't see a chicane or
speed hump, I doubt he'd see a kiddy at the side of the road.

And also the car he was following must have seen the chicane and driven
round it. If he didn't see this he shouldn't have been driving.

--
*Two many clicks spoil the browse *

Dave Plowman London SW
To e-mail, change noise into sound.