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HOW to buy online solar motion detector LED Lights with NO Lumens ratings?

gary350

Well-Known Member
I bought a 12 pack of $5 solar motion detector lights they work good and make good light.

https://www.ebay.com/itm/Outdoor-20...var=585156577255&_trksid=p2057872.m2749.l2649

I need brighter light in 3 places but no one advertises Lumens. I bought 1 of these $22 lights to see how it works, it makes 50% light than the $5 light & costs 4 times more.


I bought 5 of these UFO high bay industrial lights FREE shipping they are bright as the sun $60 at Amazon and 1 light will light up the whole front yard, 180 ft x 250 ft but no solar & no motion detector. I bought these for my work shop. I want lights with the same 21750 Lumens with solar & motion detector?????

Suggestions?


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alec_t

Well-Known Member
Most Helpful Member
I want lights with the same 21750 Lumens with solar & motion detector??
The solar panel and internal battery would both have to be a lot bigger, so perhaps not practical as a 'wall light', hence not marketed?
 

gary350

Well-Known Member
I bought a 20 LED solar light online for $5. It has built in rechargeable batteries.

I bought a 208 LED solar light online for $22. It has built in rechargeable batteries.

The 20 LED light is 2 TIMES brighter than the 208 LED light.

NO information about Lumens

Both charge during the day, they are motion sensitive after dark.

208 LED unit comes on if it rains.

20 LED unit does not come on if it rains.



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gary350

Well-Known Member
There is a different kind of solar light, each LED looks like a 3/8" glass ball cut in 1/2. I think maybe those are LEDs cast into the plastic with LEDs behind each lens. These produce a lot of bright light. 20 LED lens light up a 25 ft radius much brighter than 20 of those yellow color LEDs that make white light. I think the circuit is what makes brighter light not the LENs ?????

I don't understand why the 208 LED light makes 50% less light that the 20 LED light. ??? I need to take these lights apart and test them with my VOM.

What will kill these square shape LEDs too many volts or too many amps? I can connect batteries to the 208 LEDs to see if they get brighter.
 
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audioguru

Well-Known Member
Most Helpful Member
Any LED has a maximum allowed amount of heating. A small surface-mounted LED cannot dissipate much heat into ambient air so it cannot have much current.
A white LED has a fixed voltage of about 3.3V and if the current is 20mA then it heats with 3.3V x 30mA= =0.1W which is too much for a tiny LED. If the current is 100mA then the heating is 0.33W which will smoke it. The solar panels appear to make 5VDC. Then the rechargeable battery is a little less than 5V. If you apply more voltage then the LED current increases a lot and destroys them.

They can make the light brighter by using more current in the LEDs, then the LEDs, battery and solar panel must be larger or have higher quality.
 

gary350

Well-Known Member
Any LED has a maximum allowed amount of heating. A small surface-mounted LED cannot dissipate much heat into ambient air so it cannot have much current.
A white LED has a fixed voltage of about 3.3V and if the current is 20mA then it heats with 3.3V x 30mA= =0.1W which is too much for a tiny LED. If the current is 100mA then the heating is 0.33W which will smoke it. The solar panels appear to make 5VDC. Then the rechargeable battery is a little less than 5V. If you apply more voltage then the LED current increases a lot and destroys them.

They can make the light brighter by using more current in the LEDs, then the LEDs, battery and solar panel must be larger or have higher quality.

I finally found time to take this solar LED light apart. I tested the light in a closed dark good it make less light that some flashlights. It won't light up the bathroom enough to take a shower. Won't light up a bedroom closet very much either. This Dollar Store LED light bulb has about 15 LEDs it makes 40 times more light than this 208 LED solar light. I took the unit apart it appears solar is charging a capacitor meter reads 3.96 volts across the BLUE color thing. Is it a capacitor or battery, I short circuited the capacitor it made several spark over and over for several seconds it would not discharge so it must be a battery. Now battery voltage dropped to 3.8 volts after being discharged. I have 3AA eneloop battery pack = 4.2 vdc. I have 3AA everyready battery pack = 4.8 vdc. I wonder if it is save to replace BLUE color battery with 4,2 vdc eneloop battery back to see what happens? I think I should stay below 5 volts DC. I might be safe to use the 4.8v batteries.

WHAT is the name of these square shape yellow LEDs ?

Are all square yellow LEDs the same or different?

What to do next?

The 20 LED light makes about 4 times more light then 208 LEDs. If LEDs in both lights are the same then 208 LEDs should get much brighter with the correct circuit or correct battery.



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gary350

Well-Known Member
I tried both 4.2v and 4.9v the light is not much brighter. Close investigation what looks like yellow square LEDs are rally yellow plastic squares with a very tiny white LED behind each yellow square. This light is a SCAM all it does is make enough light so the light can be seen but no light is produces to light up anything. Look at the 3 pictures. Light hardly makes any light in this mall 7ft x 10ft room. You can see a tiny white spot center of each yellow square that is the very tiny LED on the back side of each yellow square. Beware of deceptive advertising that does not tell you Lumens and sellers that will not answer questions. This product was made to sell, it was not intended to work as a security light.

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audioguru

Well-Known Member
Most Helpful Member
The single blue battery might be Ni-MH at 1.4V and the electronic circuit steps up the voltage. But since the solar panel looks like it makes 5V then the blue battery is probably a Li-Ion cell that is fully charged at 4.2V and the electronic circuit is its charger.

A white LED is a blue one with a yellowish phosphor on top. When a manufacturer makes LEDs then some are weak rejects that are dug out of the garbage bin and used by the Security Light no-name-brand manufacturer you bought from.
If you buy a product with a Name Brand then you will get good quality with fewer LEDs. Because hundreds of good LEDs would overheat.
 

gary350

Well-Known Member
The single blue battery might be Ni-MH at 1.4V and the electronic circuit steps up the voltage. But since the solar panel looks like it makes 5V then the blue battery is probably a Li-Ion cell that is fully charged at 4.2V and the electronic circuit is its charger.

A white LED is a blue one with a yellowish phosphor on top. When a manufacturer makes LEDs then some are weak rejects that are dug out of the garbage bin and used by the Security Light no-name-brand manufacturer you bought from.
If you buy a product with a Name Brand then you will get good quality with fewer LEDs. Because hundreds of good LEDs would overheat.
I unsoldered the blue battery when I tested it meter says 3.96 VDC. Seller was from San Jose CA.

I made a mistake this light has 468 LEDs. My Batteries are 4.98 VDC 2 amps. I can try different batteries 5 VDC 8 amps.

This light is designed to charge battery all day then motion detector turns it on for 60 seconds. I will turn light OFF then let it charge in the sun for a few days then test battery to see what the voltage is.
 

audioguru

Well-Known Member
Most Helpful Member
The lie 3.96V battery cell is an 18650 sized Lithium-Ion that is fully charged at 4.2V.

Which battery you have produces 4.98V at 2A? The cheap AA Sunbeam cells are old fashioned carbon zinc that drops its voltage with a load more than 100mA (0.1A).
 

gary350

Well-Known Member
3 new D batteries soldered in series = 4.95 VDC 4.8 amps. D batteries 30 years ago were always 8 amps but not anymore. I soldered the 3 D batteries in place of the BLUE battery the 468 LED lights are not any brighter. This in not even 1 Lumen. Probably not 1/4 Lumen. It is easy to see in the dark but it makes no light. The camera sees better than me, the 2 photos taken in the dark shows it is slightly brighter than before but

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audioguru

Well-Known Member
Most Helpful Member
Super Heavy Duty batteries (carbon zinc) were made 65 years ago. A Chinese D cell one has trouble producing 100mA (0.1A). Its power drops when stored for 1 year (on the boat then in the store). They do not show a "best before" date.
A modern Energizer Alkaline D cell can produce 8A for a while. They are guaranteed to work after 10 years of storage. They show a "best before" date of 2030 or 2031 today.

Did you measure the voltage of your batteries while they powered the LEDs? Then only 3V or less?
 

gary350

Well-Known Member
Super Heavy Duty batteries (carbon zinc) were made 65 years ago. A Chinese D cell one has trouble producing 100mA (0.1A). Its power drops when stored for 1 year (on the boat then in the store). They do not show a "best before" date.
A modern Energizer Alkaline D cell can produce 8A for a while. They are guaranteed to work after 10 years of storage. They show a "best before" date of 2030 or 2031 today.

Did you measure the voltage of your batteries while they powered the LEDs? Then only 3V or less?
Volts drops to 4.85v with LED light on.
 

audioguru

Well-Known Member
Most Helpful Member
You showed a 3.96V blue battery that the solar light came with that is 4.2V when fully charged. Now you are feeding an over-voltage that might destroy the light. It is designed to be dim.
 

gary350

Well-Known Member
You showed a 3.96V blue battery that the solar light came with that is 4.2V when fully charged. Now you are feeding an over-voltage that might destroy the light. It is designed to be dim.
All this worthless light does is become visible when it comes ON so it can be seen, but it makes NO light to see other things.

Maybe I should bypass the PC board and connect battery directly to the 468 LEDs.

I have light setting where it will get sun if the clouds go away. We had snow in the forecast again tomorrow so it will be very dark gray sky with no sun. This time of the year we are lucky to have sun 5 days a month. I tried to charge blue battery today but no sun. Let it set outside all day tomorrow then I test battery to see if it is charging. I want to see if battery charges up to 4.2v
 

audioguru

Well-Known Member
Most Helpful Member
A lithium battery is extremely dangerous (explosion and fire) if over-charged but the very cheeep light might not use a proper lithium charger IC, maybe it simply does not charge to 4.2V, maybe only to 4.0V. The solar panel and battery cell are probably low quality then they cannot produce much power.
 

audioguru

Well-Known Member
Most Helpful Member
It is good to hear that the seller will replace the dim light. If the replacement works, it will probably be as dim as the bad one.
 

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