Introduction: Solar Garden Lamp Based Pendant

About: Retired educator/writer

Our early teen model, showing off her solar garden lamp based night light pendant ! These look very attractive and scope exists for kids to make a batch & sell them as "fashionable solar lamps" etc. A small profit could even be made -folks seem happy to pay ~$5 here here in NZ, especially if they could select their own ribbon from a range available!

Note: If you don't feel up to the full pendant conversion perhaps just consider the simpler  Solar Easter Egg  Instructable => https://www.instructables.com/id/Solar-Easter-Egg/

Step 1:

Solar Garden Lamps (SGL) are globally available at approx US$2 each, but often are pretty clunky or missing a switch. These new types were compact, full featured & very attractive.

Step 2:

Kid friendly colours- solar lamps have normally been black only

Step 3: Safety Alert ...

NOTE- adults should take these spikes away from kids (OR AT LEAST SMOOTH OVER THE SHARP END) as boys especially will promptly play "warriors" with them & eye damage could arise. The hollow tubes tempt as "pea shooters" as well ...

A more peaceful "waste not want not" could involve blocking the drainholes with hot melt glue -

Step 4: Rain Gauge !

- and there's an instant RAIN GAUGE ! Of course it should be higher off the ground to prevent splashes- maybe use 2 tubes to make a taller one?

Step 5: Linked Tubes?

The lamp support tubes in fact will link together quite well, perhaps to suit structural "extension" challenges. Here some Kiwi 8-10yo. scouts try to touch the ceiling with about 20 of them!

Step 6:

The lamp module features an energy efficient white LED (Light Emitting Diode), a sturdy switch, internal rechargeable AAA battery and small ( ~2V at 30mA) solar PV ( Photo Voltaic) cell. These nifty parts tempt for enhancement !

BEFORE tackling the more ambitious lamp conversion however, consider simple LED "cover" fun! .All sorts of everyday items light up a real treat when illuminated from within- wine gum sweets have been found especially suitable - see comments at end).

Perhaps the most rugged translucent covers are table tennis/ping pong balls- simply piece a hole in their bottom & place over the LED. Simple designs & messages can be further written on the ball surface to suit. Note: Try to avoid using orange table tennis balls as their colour looks rather too "flame" like & at night it may be confused with a real fire...

Step 7:

Younger kids predictably love them at bedtime, & the LED light is perfectly safe if (& WHEN !) they fall asleep. The setup will of course later need daylight recharging. Just tipping the lamp over (so the PV "sees the sun") may do, but a small hole drilled in the side allows threading a cord to suit hanging at a sunny window etc.

NOTE: Although it suits convenient night time on/off action, THE LAMP SWITCH MUST BE ON FOR DAYTIME CHARGING TO OCCUR !

Step 8: LED Lamp Module Enhancement

But the lamp module further tempts for enhancement by LED repositioning - follow the next few steps for insights. You'll need just a small Philips head screwdriver & simple tools, but things are a tad fiddly & adult help will be almost certainly needed.

NOTE: Lamp variations have emerged, and the model shown here is a 2011 era. By 2014 the lamp had simplified with fewer screws and a smaller switch - best to check details of exactly what's on offer before rushing in,especially for a group project!

Step 9: Pre Opening Parts Alignment Alert !


Before removing and modifying the module it's suggested that small felt tip pen alignment marks are made to ensure correct reassembly. Excessive twisting around of the top & base may otherwise occur,leading to broken wires... When it's revealed (after case opening) perhaps also add similar ID marks ( +/-) for the battery. This ensures CORRECT polarity replacement if it's removed.

Step 10: Open Sesame !

The lamp module easily opens with a small Phillips head screwdriver - the outer case on this lamp has 3 (black) with the small circuit board inside another 2 (silver). Some lamps however have fewer. Don't misplace the screws- perhaps put them in a small dish!

Step 11:

For improved working space when rotating the circuit board, perhaps ease back the battery tab & remove the rechargeable AAA cell. This alone is worth a few $ and perhaps handy for other projects !

Step 12:

Carefully lift out the small printed circuit board ( PCB) that holds the switch and white Light Emitting Diode (LED) . AVOID BREAKING WIRES or they'll need to be resoldered !   The lamp basics are examined in more detail at the Instructable end, but essentially  by day the small solar panel both charges the battery AND keeps the lamp ( unless the PV is covered!). After dark the electronics sense no charging is occuring and  the LED lamp is turned on. Yah!  It'll run for about 3 hours for every bright sunshine charging hour. 

NOTE: Although it allows convenient night time on/off action, THE SWITCH MUST BE ON FOR DAYTIME CHARGING TO OCCUR !

Step 13:

Carefully rotate the small PCB  half a turn so it's  LED is now poking out the front, and ensure the switch goes back into the slot OK. Screw back down this small circuit board and reinsert the battery - make sure it's put back in the right way around of course!  The LED leads can be carefully bent  towards the side hole that will be drilled into the plastic case.

Step 14:

3 holes now need drilling - 2 for the supporting cord  and one for the LED. The exact size & positions of these holes is not too critical but the picture shows a suitable layout. Use a small drill bit initially to avoid wandering, then drill this out with a larger bit ( ~ 7mm for the LED ?) to size. The cord leads will need smaller holes of course, but even then tie several sturdy knots at the cord/ribbon ends to prevent pull thru'.   Gently bend the LED leads to ensure it smoothly fits into the new hole - don't jam it in or wires may be broken!  Ensure no wires are crimped when when the case is closed either.

Step 15:

Pendants naturally suit hanging vertically, which further favours valuable low angle sunshine - the light goes straight down ( rather than being wasted up/in your eyes) as well. Visit a craft shop for ribbons &  cords to add a decorative touch!  Once corded, either hang it on a window hook or wear around neck etc. 

Step 16:

The plastic rim around the previous LED hole should be trimmed flat at this stage - it'll get in the way of the round lable otherwise. It can be nibbled with sidecutters or perhaps even drilled away.

Step 17: Descriptive Label Etc.

Make a neat NAMED label & cover with clear tape or Duraseal for protection

Step 18:

A  craft blade neatly  cuts out the label's OFF/ON  box, and it can be used to better seat this label as well. Care with the sharp blade!

Step 19:

Trimmed to size & secured with gluestick

Step 20: Finished Item

Et voila ! This sample uses a shoelace & the cord is hence rather too short for most people.

Step 21: On Display

Miss 2011 ! 

Step 22: Bedside Etc


Of course the pendant style also allows hanging on a sunny hook etc for an "auto on" bedside lamp. The vertical PV particularly suits solar pickup of the otherwise fleeting low angle winter sunshine. Ensure the PV  faces into the sunbeams of course !

Step 23: TECHNICAL DETAILS

Internals - features the now conventional ZE002 'quadistor" - details however elusive... That "resistor" is an inductor (~470 µH)

Step 24:

Pulses at ~ 400kHz

Step 25:

ZE002 probably an Asian Zetex ?

Step 26: ALTERNATIVE - Parts Revealed

Past educational sectioned display- discrete circuitry

Step 27: ALTERNATIVE- Parts Revealed

Another past display- uses ZE002 IC & inductor