solar spotlight

[broschultz]

Looking for a solar spotlight to light up a sign so it can be read, more or less, from 50 feet away. Any suggestions?

[LCHIEN]

a whole bunch of questions arise, such as:

1. is the light or the viewer 50 feet away?
2. if the ans to 1 is the viewer, how far away can the light be?
3. What latititude do you live in, whats the average days of sun, what percentage overcast is it going to be? How critical is it to be lit every night or if its overcast for too many days in a row is it OK to be off for a few nights?
4. How many hours do you want it lit, all night or just for a few hours after sunset?
If all night, how long does night last at your location on Dec 21?
5. How long a lifetime do you need - all of these will need secondary batteries and the lifespan of batteries like Nicd, NiMH, and Lead acid will onkly be 2 or three years at the most.
6. Temperature range? Most rechargeable batteries lose capacity when cold. Life is greatly reduced when too hot.
7. is the location of the solar panel going to be in clear sky view all day long?
8. is the sign being lit in a very dark area, or an area partially lit - i would expect more light is needed if in a partially lit area.

These are all critcal factors, but even if i had your answers to them, I still would not have a suggestion.

[dbhost]

I might, and Loring had the right suggestions on the info needed...

But to boil it down to soup & nuts. You will need...

#1. Some sort of solar panel / battery charger.
#2. Some sort of rechargable battery system.
#3. Some sort of DC powered flood light...

For the solar panel / charger, you might want to look into the 6 or 12V panels / chargers and 6V or 12V batteries used for deer feeders. I have 6 of them and have to replace the batteries every 2 years in north / west Texas. (VERY hot in summer, VERY cold in winter, brutal on batteries...).

For the flood light, you will want some 6 or 12V LED flood lights and fixtures. Again Sporting goods stores / hunting supply outfitters usually have these... We need flood lights around the bunk house, particularly around the Gambrel (No I don't mean the roof truss design, I mean the rack for holding an animal that is being field dressed...).

The hunting supply shops in your area would be best suited to what works in your environment, or if at all. A lot of states don't allow feeders, and I am not going to even think of the legality of hunting outside of the U.S.A., because I don't know...

[leehljp]

I am going to say that I have been impressed with LED lights and on occasion see some VERY good sales on them over here. But most of the time they are EXPENSIVE.

[broschultz]

The viewer will be about 50 feet from the sign but the light will be about 7 feet. It's not important that the light stay on all night. 6 hours are good. It will be used on Long Island in NY. I'm looking at solar spot lights that come with a small solar cell.

[capncarl]

On base here we use a good bit of solar powered lights, street lights and yield/stop/pedestrian signs. None seem to hold up well. The solar power signs with blinking led's do last longer but still not worth the several thousand that they cost each. The street lights put out a fair amount of light and are expected to run all night. If they were only putting out enough light to illuminate a sign I suppose that they would last all night. As the daylight hours get shorter the battery recharge gets less, throw in a couple of cloudy days and you have no light. Snow would stop the charging completely.
capncarl

[LCHIEN]

As i stated before i have no experience with these, however, i am familiar with the engineering excercise to running instrumentation equipment from a solar panel for 24/7.

Most lights are, I consider, consumer grade and have no 24/7 requirements and like HF units, are probably made as cheaply as possible.

Ones that can gather enough light power and have a large enough battery to ride out dark days and still have the panel in a fixed position (no active aiming at the sun) requrie large panels and big batteries.

In a cheap unit just to keep things lit for the evening (such as pathways, signs), they will try and use the smallest possible battery and solar panel to keep it cheap-thei prime goal. The light will probably run down the battery to zero often - during long nights and dark days, if not every night. Batteries let run down to zero will result in reverse charging any other cells in the unit, resulting in reduced life (worse than the cold and hot reduction issues). Circuits to cut off the lights when the batteries are low but not zero add to the cost.

That's why I wouldn't have a consumer unit of this kind. Industrial units are likely to have much greater cost. LED units as noted will make the lights run brighter with less current, but the LEDs are more expensive, but probaly not more expensive than bigger solar cells and battery cells if you are buying a commercial grade unit..