Solar lighting - What do the specs really mean, how much light can I actually expect to get and for how long?

[Crossy]

1 hour ago, sometimewoodworker said:

I fairly sure that if it’s a lithium ion cell then it’s a fake number or a dangerous fire hazard.

 

Or both even.

 

How about a DIY battery capacity tester? https://www.opengreenenergy.com/post/arduino-battery-capacity-tester-v2-0

 

 

Or 500 Baht or so will buy you one

https://www.lazada.co.th/products/8-in-1-150usb-i1654540670-s4601582727.html

 

[Peterphuket]

53 minutes ago, Susco said:

I tested my lamps last night for only a few minutes to check the brightness, and that was very satisfying. Since yesterday was a cloudy day, I decided to charge them for a second day before testing the endurance.

 

These are some observations so far,

 

- Brightness is good, even at dimmed all night strength it is sufficient for my purpose.

 

- I watched a customer feedback video, where I noticed he covered the solar panel, and the lights would turn on without covering the photocell. Tried this just here during day time and got the same result. Covering only the photocell would not activate the lights.

Is this normal behaviour?

 

- Shopee and Lazada definitely need to get their act together. The model of the light is SH-078, entering that in the search bar of Shopee gives me 6 results from 225 to 295 Baht. In Lazada  that gives 11 results from 279 to 790 Baht, all with the same package pictured as I received.

 

Now giving SH-078 in Google shows me a Thai website which has a Shopee listing at 160 Baht.

If I click on that listing, I'm taken to the Shopee Thailand website, and from that listing by clicking suggested items at the bottom, I can find at least 6 other sellers selling the product, all below 200 Baht. All listing have the item in stock

So why is it impossible to find these in the Shopee search?

 

I have the same experience with many items at Lazada aswel at Shopee, but there is also a diferent when you use a different browser.

Sometimes it makes you crazy when you searching for a particular item.

When I find an item from which I thinking this is the lowest price I put it on "My favorites" list. or ad to cart list.

[Susco]

1 hour ago, Crossy said:

 

Or both even.

 

How about a DIY battery capacity tester? https://www.opengreenenergy.com/post/arduino-battery-capacity-tester-v2-0

 

 

Or 500 Baht or so will buy you one

https://www.lazada.co.th/products/8-in-1-150usb-i1654540670-s4601582727.html

 

 

While the Lazada one looks decent with the big fan, found this one on Bangood for 270 Baht

 

https://sea.banggood.com/th/XH-M240-Battery-Capacity-Tester-mAh-mWh-for-18650-Lithium-Battery-Digital-Measurement-Lithium-Battery-Power-Detector-Tester-Voltmeter-p-1616147.html?rmmds=buy&cur_warehouse=CN

 

Or 140 Baht for the same one on Lazada

 

https://www.lazada.co.th/products/xh-m240-battery-capacity-tester-mah-mwh-for-18650-lithium-battery-digital-measurement-lithium-battery-power-detector-tester-voltmeter-i1466062113-s3837610405.html

[Susco]

@Crossy  Have you seen this product? This is similar to that Arduino tester or not?

 

https://www.lazada.co.th/products/supplies-battery-tester-equipment-power-external-multimeter-components-pzem-015-dc-voltage-i1757316980-s5086536449.html?

 

[Crossy]

4 minutes ago, Susco said:

@Crossy  Have you seen this product? This is similar to that Arduino tester or not?

 

That looks more like a monitor than a tester (aimed at those with off-grid power systems). The Arduino unit (there are loads of things on Lazada too) actually measures the capacity in Ah / Wh so you know if the battery is good, bad or indifferent.

 

This is probably the cheapest "decent" tester https://www.lazada.co.th/products/1xgreen-ccl-150w-60v-10a-battery-discharge-capacity-tester-16107cm-i1824894807-s5487116750.html

@ 360 Baht.

 

[nobodysfriend]

I bought and installed these 45W lights .

Modified a little to fix the solar panels directly to the lights .

They do not get full sun all day .

They turn on at dusk and off 3 hours later . Works fine . no problems until now .

The solar panel must be covered by glass , not polyester .

Poly darkens with time and makes the lights ineffective .

45W is enough for my wife to find her way back at night ...

[roodujardin]

On 11/30/2020 at 12:33 PM, Crossy said:

 

I can quite believe that fake batteries are out there just like fake flash cards.

There's plenty of fake batteries out there. Batteries of course are the weakest component of a solar system. I've bought quite a few solar kits from Lazada and the batteries are always the first to go. Sometimes very quickly, sometimes they last a year or so. 

 

Being annoyed with this l a) taught myself how to replace a battery in these kits and b) bought a battery capacitance tester. One of the best investments l've made; only about 200baht for a basic tester. This is all you need. My first battery test showed a new 18650 battery rated at 9800mah had an actual capacitance of 980mah. They print their own battery wrapping with bogus specs. 

 

A capacitance tester is also useful for those cordless tools that have died because of lousy batteries. All my dead cordless tools are again up and running with decent batteries of known capacitance. 

 

I've found that building a serious solar system in Thailand takes a lot of trial and error and a heap of component testing. Most parts come from China and obtaining quality can be difficult. Testing tools are a must if DIY. 

[Crossy]

16 minutes ago, roodujardin said:

rated at 9800mah had an actual capacitance of 980mah

 

Semantics I know, but please call it "capacity", "capacitance" is something very different.

 

Oh and it's "A" for "ampere", a small "a" is for "atto", 10^-18 not a very large number at all.

 

It really does matter, the difference between "M" and "m" is a factor of 1,000,000,000 probably fairly significant.

[Crossy]

On 11/30/2020 at 2:16 PM, Rimmer said:

Oh yes,  I think there is a mode to follow and I can't remember what it is, I tried doing with it off and with it on and with it on auto first but it took a few permutations to get it right.

 

I think I've sussed it:-

 

With the panel disconnected (or in the dark) press on (light comes on), off (light goes off), then the required time (light comes on).

 

The initial "on" may not be needed but it seems to want the charger to be disabled, it being dark was the only thing I did differently this time.

 

Weird!

 

[Susco]

My light are now going for 17 hours already, so few more questions.

 

They are on half power, because the setting is that full power is only possible if the movement sensor get triggered.

 

Can I just short the movement sensor to have them constant on full power?

 

If the lights run X hours on half power, does that mean they will run  X ÷ 2 on full power, or is that not a fact?

[Crossy]

35 minutes ago, Susco said:

Can I just short the movement sensor to have them constant on full power?

 

If the lights run X hours on half power, does that mean they will run  X ÷ 2 on full power, or is that not a fact?

 

Movement detector - Possibly, but not guaranteed, it all depends how it's set up internally.

 

Power - Another "it depends" I'm afraid, it will certainly last a shorter time on full brightness but how much shorter is difficult to say without some measurements. Can you check the battery current with it on dim and bright?

 

Please feel free to start another thread or PM me some photos of the important bits of the internals so we can try to work out what's possible. Is the same light available without the movement sensor??

 

[Susco]

3 minutes ago, Crossy said:

Power - Another "it depends" I'm afraid, it will certainly last a shorter time on full brightness but how much shorter is difficult to say without some measurements. Can you check the battery current with it on dim and bright?

 

I have a multimeter that has a DC Amp setting. Can you explain how to measure. Light is still going now

 

4 minutes ago, Crossy said:

Please feel free to start another thread or PM me some photos of the important bits of the internals so we can try to work out what's possible. Is the same light available without the movement sensor??

 

I will take a picture of the PCB and PM you, but is a very simple board with only few components on it

[Crossy]

1 minute ago, Susco said:

I have a multimeter that has a DC Amp setting. Can you explain how to measure. Light is still going now

 

You have to disconnect one of the battery leads and put your DMM in series with it on the "DC Amps" range. One lead of the DMM on the battery where you removed the lead, the other on the lead you removed from the battery.

[thaicookingchef]

Sorry, can I know what is the cheapest solar light that I can buy to have light for digs at night ?

 

thank you.

 

[Crossy]

Spurred on by the reasonable performance of the flood light I bought three of the "150W" version of these:-

https://www.lazada.co.th/products/i1330690542-s3321646144.html

Ordered Tuesday morning, delivered Wednesday afternoon (despite saying 2 day delivery), cant fault that.

 

In the box is the light itself, 28W solar panel, the mounting tube, the brackets for the panel the remote (no batteries) and a bag of nuts, bolts and washers. All looks pretty ok and the cover comes off so replacing the batteries shouldn't be an issue.

 

Removing the cover and the Bacofoil reflector reveals the works.

 

 

Inside is a 3.2V 20Ah GN 32650 pack, looks like 5 x 32650 cells making them 4Ah each. Note that this is not the 32Ah pack promised by the Lazada spec page.

 

 

Left in the sunshine all morning and checked the battery current when ön

 

 

Battery voltage was 3.15V so with 3.58A we have about 11.3W, acceptable for my purposes but not the 15W or so I was expecting given the "150W" rating on the box.

 

One important fact was that I had to use my clamp meter, inserting my regular DMM on 10A range upset the electronics and the beast only came on dimly.

 

I also note that "DIM" appears not to function although it's possible that what we have is "DIM" and "BRIGHT" isn't working because the batteries aren't fully charged yet, we shall see how things pan out after more sunshine.

 

Also, the provided hardware doesn't include a pole mounting kit, wall mount as supplied. No problem as I'm mounting mine on our power poles using custom made brackets.

 

You will need your "assorted nutz, boltz, scrooze and washerz" box as there are (as usual) nowhere near enough washers provided and the bolts intended for the solar panel are way too small.

 

More coming soon.

 

 

 

[solafr]

26 minutes ago, Crossy said:

Spurred on by the reasonable performance of the flood light I bought three of the "150W" version of these:-

https://www.lazada.co.th/products/i1330690542-s3321646144.html

Ordered Tuesday morning, delivered Wednesday afternoon (despite saying 2 day delivery), cant fault that.

 

In the box is the light itself, 28W solar panel, the mounting tube, the brackets for the panel the remote (no batteries) and a bag of nuts, bolts and washers. All looks pretty ok and the cover comes off so replacing the batteries shouldn't be an issue.

 

Removing the cover and the Bacofoil reflector reveals the works.

 

 

Inside is a 3.2V 20Ah GN 32650 pack, looks like 5 x 32650 cells making them 4Ah each. Note that this is not the 32Ah pack promised by the Lazada spec page.

 

 

Left in the sunshine all morning and checked the battery current when ön

 

 

Battery voltage was 3.15V so with 3.58A we have about 11.3W, acceptable for my purposes but not the 15W or so I was expecting given the "150W" rating on the box.

 

One important fact was that I had to use my clamp meter, inserting my regular DMM on 10A range upset the electronics and the beast only came on dimly.

 

I also note that "DIM" appears not to function although it's possible that what we have is "DIM" and "BRIGHT" isn't working because the batteries aren't fully charged yet, we shall see how things pan out after more sunshine.

 

Also, the provided hardware doesn't include a pole mounting kit, wall mount as supplied. No problem as I'm mounting mine on our power poles using custom made brackets.

 

You will need your "assorted nutz, boltz, scrooze and washerz" box as there are (as usual) nowhere near enough washers provided and the bolts intended for the solar panel are way too small.

 

More coming soon.

 

 

 

 

Hello, so you recommend to buy the same ? or any cheaper one that is also good ? thanks.

 

 

[Crossy]

26 minutes ago, solafr said:

Hello, so you recommend to buy the same ? or any cheaper one that is also good ? thanks.

 

The lights only came yesterday so until I get them up on the poles and see some real life lighting and duration I can't recommend anything.

 

I'm a little disappointed at the installed 20Ah (64Wh) battery pack as the spec. on the sellers page says 32Ah (102Wh), the 28W panel will generate around 90Wh on a reasonable day so a good 30% of the generated power is being wasted and at the measured 11W we could only get about 6 hours of light.

 

We shall have to see how it goes, 32650 cells are not horribly expensive so making up a larger pack is a possibility, there's a fair bit of room in the box for a couple more cells.

 

[Led Lolly Yellow Lolly]

On 11/28/2020 at 7:29 AM, Crossy said:

The batteries finally failed after about 18 months.

 

 

 

 

 

 

This is why I've resisted pressure to invest in solar lighting at our properties. Everyone around me thinks it a great idea, but I'm not bowled over, primarily because I know the batteries sit in the blazing sun and heat all day. The cost of constantly replacing those must surely negate any savings, not to mention the annoyance of that. If I were to take the solar route, I'd build them myself, and use Lithium Iron Phosphate batteries (or maybe even supercapacitors), and only use them where mains power was impossible or extremely inconvenient to cable in.

 

Note that I do use a lot of solar. We have some remote camera sites where there is no mains power. The feed is transmitted over a microwave link back to base. I use Lead Calcium batteries for those remote sites, and the cabinets are forced air cooled, mainly for the longevity of the batteries, usually replace every 3 ~ 5 years. High temperatures are DEATH to most batteries chemistries.

 

 

 

 

[Crossy]

Got two of the streetlights up before it got too hot.

 

 

This is my custom bracket. The square plate is 150mm x 150mm x 4mm steel (60 Baht from our local steel man). The 3/8" studding goes through the pre-cast hole in the power pole and gets well wanged up so nothing moves, the 50mm big black washer was stock from an aborted project. The bolts holding the light itself are 8mm countersunk so the heads are flush on the back of the plate. Primed and painted to match the light fitting.

 

 

A test last night showed the lights do stay on all night but the brightness is well down after 12 hours and I still can't make "DIM" mode work.

 

I may add a couple of cells to one unit (plenty of room) and see just how much difference it makes, as noted earlier the panel has loads of spare energy that we're not using.

 

 

 

[AlfHuy]

Pay attention that your own "street light" won't be removed soon.

[Crossy]

9 minutes ago, AlfHuy said:

Pay attention that your own "street light" won't be removed soon.

 

They're not actually in the street, they light our driveway.

 

Anyone who wants to purloin them will need to get past the moat (yes we have a moat, but no crocodiles) and a 2m wall followed by our geese and guinea fowl who would awaken two bloodthirsty rottweilers (who would likely lick them to death).

 

They would also need a ladder as they are >3m up the poles.

 

 

[Muhendis]

3 hours ago, Crossy said:

They would also need a ladder as they are >3m up the poles.

Standard rule for most things wall/post mounted......Two drunks high.

[Crossy]

1 minute ago, Muhendis said:

Standard rule for most things wall/post mounted......Two drunks high.

 

Yup, but they would likely be Thai drunks ???? 

 

And the one at the bottom would be being eaten alive.

[thaicookingchef]

On 12/10/2020 at 2:31 PM, Crossy said:

Spurred on by the reasonable performance of the flood light I bought three of the "150W" version of these:-

https://www.lazada.co.th/products/i1330690542-s3321646144.html

Ordered Tuesday morning, delivered Wednesday afternoon (despite saying 2 day delivery), cant fault that.

 

In the box is the light itself, 28W solar panel, the mounting tube, the brackets for the panel the remote (no batteries) and a bag of nuts, bolts and washers. All looks pretty ok and the cover comes off so replacing the batteries shouldn't be an issue.

 

Removing the cover and the Bacofoil reflector reveals the works.

 

 

Inside is a 3.2V 20Ah GN 32650 pack, looks like 5 x 32650 cells making them 4Ah each. Note that this is not the 32Ah pack promised by the Lazada spec page.

 

 

Left in the sunshine all morning and checked the battery current when ön

 

 

Battery voltage was 3.15V so with 3.58A we have about 11.3W, acceptable for my purposes but not the 15W or so I was expecting given the "150W" rating on the box.

 

One important fact was that I had to use my clamp meter, inserting my regular DMM on 10A range upset the electronics and the beast only came on dimly.

 

I also note that "DIM" appears not to function although it's possible that what we have is "DIM" and "BRIGHT" isn't working because the batteries aren't fully charged yet, we shall see how things pan out after more sunshine.

 

Also, the provided hardware doesn't include a pole mounting kit, wall mount as supplied. No problem as I'm mounting mine on our power poles using custom made brackets.

 

You will need your "assorted nutz, boltz, scrooze and washerz" box as there are (as usual) nowhere near enough washers provided and the bolts intended for the solar panel are way too small.

 

More coming soon.

 

 

 

 

 

1000 thb for 150W ?

similar 150W cost 2500 at WATSADU !

is there anything else to check to compare the quality ? I would like to know if the ones that you bought are exactly similar as the 2500 watsadu ?

thanks.

 

 

[Crossy]

1 minute ago, thaicookingchef said:

1000 thb for 150W ?

similar 150W cost 2500 at WATSADU !

is there anything else to check to compare the quality ? I would like to know if the ones that you bought are exactly similar as the 2500 watsadu ?

thanks.

 

To be honest, without buying one of each it's going to be difficult.

 

The box ours came in has this label.

 

 

Could be worth asking Watsadu to see the boxed unit and compare.

 

[Muhendis]

I just did a search for that street light and found these demo's

 

https://www.youtube.com/watch?v=c-2lAmuu-Ag

https://www.youtube.com/watch?app=desktop&v=5ZEMZGl8DIU

 

Quite impressive although the dim setting seems a bit bright. Thanks to Crossy for sharing, I'm thinking about getting one or two myself.

 

[Muhendis]

Looking back at the picture of the pole mounted unit, I think I would be tempted to rearrange the solar panel to shade the top side of the lamp. As has been mentioned, heat and batteries don't go well together so every little helps.

[Crossy]

42 minutes ago, Muhendis said:

Quite impressive although the dim setting seems a bit bright.

 

The dim setting is one thing that doesn't work on mine (the light doesn't acknowledge the setting), too late to complain now. Even on full power they are still giving acceptable light at 6AM so no issue for me really.

 

I may make up a "max that will fit" battery pack (7 cells, about 35-42Ah) to see whether they will then run at full power all night. The panel should produce about 100Wh on a decent day so the bigger pack will ensure all that is stored.

 

[WalterVandervort]

Any thoughts on the TENKOO LED Solar Street Lights of products? I've been happy with them for my garden. They make other models as well, higher and lower current.

[tjo o tjim]

I wonder what they have in the way of a charge controller and low voltage cut-out for these things. No matter the brand, I feel lucky to get about full 100 cycles on the consumer units (and only ~300 with commercial units).  I have had little luck replacing batteries, even when it is possible— the charging circuits are not very forgiving for new batteries.