Posted by F Murtz on June 20, 2011, 3:03 am
The Other Mike wrote:
> Currently got a remote observation site (wildlife) with no grid fed
> power nor any prospect of it.
> Half the site has a few modified 4ft T5's (36W) retrofitted with 12v
> IOTA Ballasts (2D12-1-32) fed from a lead acid battery charged by a
> solar panel. The other half of the site has 5ft T5's with magnetic
> ballasts fed by a Honda EU20i generator which despite being a quiet
> suitcase model and loads of additional soundproofing is still way too
> noisy. Near silent operation is essential. Hauling fuel is also a
> PITA as its a long way from the road.
> So I need a way of powering the 5ft T5's (58W) from a low voltage DC
> supply. IOTA only make ballasts up to 40W and they need a circa 50v
> supply, realistically I need to keep to 12v to keep the solar array
> price down.
> So thoughts turned to an inverter fed from an uprated solar array and
> battery.
> A cheap modified sine wave inverter (circa 500W capacity) on a 100Ah
> brand new battery fails to even kick even one 5ft tube into life. The
> manufacturer says these inverters are not compatible with fluorescent
> tubes but doesn't elaborate any further.
> Does anyone have any ideas on how to get these lights working off
> grid?
> A change of ballast to an electronic type? (all indications are this
> could won't work?)
> Moving to a pure sine wave inverter (extremely expensive) ?
> A different inverter supplier rather than 'one hung lo china inc' ?'
> A ballast supplier that offers 12v ballasts that will drive a 58W
> tube?
> A homebrew 12V fluorescent inverter, running at high frequency that
> will drive 5ft tubes and costs not a lot? :)
Try this, and oatleyelectronics have lots more goodies.
http://secure.oatleyelectronics.com//product_info.php?cPath 0_108&products_id"9&osCsid=e1382db5b7e8301a03011e405258f2ca
Posted by Tabby on June 20, 2011, 3:43 am
On Jun 19, 11:52pm, The Other Mike
> Currently got a remote observation site (wildlife) with no grid fed
> power nor any prospect of it.
> Half the site has a few modified 4ft T5's (36W) retrofitted with 12v
> IOTA Ballasts (2D12-1-32) fed from a lead acid battery charged by a
> solar panel. The other half of the site has 5ft T5's with magnetic
> ballasts fed by a Honda EU20i generator which despite being a quiet
> suitcase model and loads of additional soundproofing is still way too
> noisy. Near silent operation is essential. Hauling fuel is also a
> PITA as its a long way from the road.
> So I need a way of powering the 5ft T5's (58W) from a low voltage DC
> supply. IOTA only make ballasts up to 40W and they need a circa 50v
> supply, realistically I need to keep to 12v to keep the solar array
> price down.
> So thoughts turned to an inverter fed from an uprated solar array and
> battery.
> A cheap modified sine wave inverter (circa 500W capacity) on a 100Ah
> brand new battery fails to even kick even one 5ft tube into life. The
> manufacturer says these inverters are not compatible with fluorescent
> tubes but doesn't elaborate any further.
> Does anyone have any ideas on how to get these lights working off
> grid?
> A change of ballast to an electronic type? (all indications are this
> could won't work?)
> Moving to a pure sine wave inverter (extremely expensive) ?
> A different inverter supplier rather than 'one hung lo china inc' ?'
> A ballast supplier that offers 12v ballasts that will drive a 58W
> tube?
> A homebrew 12V fluorescent inverter, running at high frequency that
> will drive 5ft tubes and costs not a lot? :)
I think you'd benefit greatly from zooming out for a rethink. You'er
asking for low voltage panels to charge a 12v battery, which will then
get upconverted to 240v which must be done the expensive sine way,
which will then be downconverted to 35v to run the tubes. Its madness.
Far more practical wuold be warm white LEDs that will run off 12v via
a resistor or constant current regulator. Take a look at
rapidonline.co.uk, if you can wade through the long list of led
options you'll find some very satisfactory deals there. No need for a
240v invertor anywhere, or problematic ballasts, no compatibility
issues, and LEDs are far longer lived, far more robust and much more
versatile than fl tubes, and trivial to dim to save power.
NT
Posted by The Other Mike on June 20, 2011, 11:31 am
wrote:
>I think you'd benefit greatly from zooming out for a rethink. You'er
>asking for low voltage panels to charge a 12v battery, which will then
>get upconverted to 240v which must be done the expensive sine way,
>which will then be downconverted to 35v to run the tubes. Its madness.
>Far more practical wuold be warm white LEDs that will run off 12v via
>a resistor or constant current regulator. Take a look at
>rapidonline.co.uk, if you can wade through the long list of led
>options you'll find some very satisfactory deals there. No need for a
>240v invertor anywhere, or problematic ballasts, no compatibility
>issues, and LEDs are far longer lived, far more robust and much more
>versatile than fl tubes, and trivial to dim to save power.
I can't see the economics working, yes its wasteful with multiple
stages of conversion but the fluorescents are already there, also
LED's seem way more expensive because of the number of light sources
required.
Dimming isn't a requirement. Its for work lighting as its a near
windowless building, the requirement is for an even spread of light
such as provided by a fluorescent tube (operating microscopes and
laptops in the same room is very common occurrence)
T5 fluorescents are somewhere around 70-100 lumens per watt. Most
LED's at appear to be much lower efficiency with a holey spectrum and
providing a very directional light source. but I'll ignore those
deficiencies for now.
Currently there are I guess somewhere around 17000 lumens lighting an
area of about 20 x 8ft so make that around 1000 lux, but we might get
away with a little bit less.
At about the typical "90 lumens" per white LED package that would
require about 180 separate light sources costing anything from GBP 2 -
4 a piece. All requiring heatsinking and being around 1/3 the
efficiency of the fluorescents, almost certainly requiring a bigger
solar array and a bigger battery.
So before those LED's are mounted and wired that's GBP 500 - 700 for
the equivalent of the fluorescents that are already in situ which cost
significantly less than a 10th of that.
GBP 500-700 buys a very nice pure sine inverter.
--
Posted by Dave Liquorice on June 20, 2011, 1:36 pm
On Mon, 20 Jun 2011 12:31:37 +0100, The Other Mike wrote:
> At about the typical "90 lumens" per white LED package that would
> require about 180 separate light sources costing anything from GBP 2 -
> 4 a piece.
LED lighting is evolving very quickly, you can get strips these days
with LEDs mounted every few inches, rather individual "bulbs".
I wouldn't like to say how their efficiency compares to florry
though...
Or there are GU10 LED or R50 sized reflectors that only take a watt
or two at mains voltages. The aldli/lidl 3W Warm White 3000K LED R50
ES "reflector" I got to try is a pretty close match to a 60W R50 ES
tungsten.
"Livarno EdiLight".
Directional of course not spray light everywhere like a florry.
--
Cheers
Dave.
Posted by Tabby on June 20, 2011, 2:20 pm
On Jun 20, 12:31pm, The Other Mike
> wrote:
> >I think you'd benefit greatly from zooming out for a rethink. You'er
> >asking for low voltage panels to charge a 12v battery, which will then
> >get upconverted to 240v which must be done the expensive sine way,
> >which will then be downconverted to 35v to run the tubes. Its madness.
> >Far more practical wuold be warm white LEDs that will run off 12v via
> >a resistor or constant current regulator. Take a look at
> >rapidonline.co.uk, if you can wade through the long list of led
> >options you'll find some very satisfactory deals there. No need for a
> >240v invertor anywhere, or problematic ballasts, no compatibility
> >issues, and LEDs are far longer lived, far more robust and much more
> >versatile than fl tubes, and trivial to dim to save power.
> I can't see the economics working, yes its wasteful with multiple
> stages of conversion but the fluorescents are already there, also
> LED's seem way more expensive because of the number of light sources
> required.
> Dimming isn't a requirement. Its for work lighting as its a near
> windowless building, the requirement is for an even spread of light
> such as provided by a fluorescent tube (operating microscopes and
> laptops in the same room is very common occurrence)
> T5 fluorescents are somewhere around 70-100 lumens per watt. Most
> LED's at appear to be much lower efficiency with a holey spectrum and
> providing a very directional light source. but I'll ignore those
> deficiencies for now.
> Currently there are I guess somewhere around 17000 lumens lighting an
> area of about 20 x 8ft so make that around 1000 lux, but we might get
> away with a little bit less.
> At about the typical "90 lumens" per white LED package that would
> require about 180 separate light sources costing anything from GBP 2 -
> 4 a piece. All requiring heatsinking and being around 1/3 the
> efficiency of the fluorescents, almost certainly requiring a bigger
> solar array and a bigger battery.
> So before those LED's are mounted and wired that's GBP 500 - 700 for
> the equivalent of the fluorescents that are already in situ which cost
> significantly less than a 10th of that.
> GBP 500-700 buys a very nice pure sine inverter.
Rapid do white LEDs for 1.50 per 100 lumens, 17000l in whites = 255=
.
Colours are cheaper, except blue which you wont need, there's plenty
of that from the white LEDs.
Spectrum is addressed by mixing white LEDs with coloured ones to
create the white you're after.
Directionality is a nonissue with uplighting.
Ali sheet's not expensive
If yuo'd rather go with the T5s, you either need a sine wave invertor
or some electronic ballasts. Those and HID are the options really.
NT
XML site map
> power nor any prospect of it.
> Half the site has a few modified 4ft T5's (36W) retrofitted with 12v
> IOTA Ballasts (2D12-1-32) fed from a lead acid battery charged by a
> solar panel. The other half of the site has 5ft T5's with magnetic
> ballasts fed by a Honda EU20i generator which despite being a quiet
> suitcase model and loads of additional soundproofing is still way too
> noisy. Near silent operation is essential. Hauling fuel is also a
> PITA as its a long way from the road.
> So I need a way of powering the 5ft T5's (58W) from a low voltage DC
> supply. IOTA only make ballasts up to 40W and they need a circa 50v
> supply, realistically I need to keep to 12v to keep the solar array
> price down.
> So thoughts turned to an inverter fed from an uprated solar array and
> battery.
> A cheap modified sine wave inverter (circa 500W capacity) on a 100Ah
> brand new battery fails to even kick even one 5ft tube into life. The
> manufacturer says these inverters are not compatible with fluorescent
> tubes but doesn't elaborate any further.
> Does anyone have any ideas on how to get these lights working off
> grid?
> A change of ballast to an electronic type? (all indications are this
> could won't work?)
> Moving to a pure sine wave inverter (extremely expensive) ?
> A different inverter supplier rather than 'one hung lo china inc' ?'
> A ballast supplier that offers 12v ballasts that will drive a 58W
> tube?
> A homebrew 12V fluorescent inverter, running at high frequency that
> will drive 5ft tubes and costs not a lot? :)