Solar Powered Garden Light

It looks like a 200 ohm from the picture: bad boys r*** our young girls ... (not pc anymore)

I would say the most likely problem is corrosion. I think the most common problem is that moisture gets inside, and where you live, it probably has a bit of sea salt as well.

Certainly no longer PC, but then which young lad would forget violet?

Definitely not PC, but definitely effective! I just remembered the phrase yesterday, while helping someone, but avoided telling them.... Anything I still remember from over 60 years ago was clearly taught effectively! Unfortunately, I never met violet!

Looks like a cold solder joint. I would heat the pad and resistor lead then flood the joint with solder. If it still works you're done. Weird that it is a precision resistor (the gold band), though.

Nope! It's not a precision resistor! Only four bands total. Gold (which I can't see on either of these photos) signifies 5%. To me, precision resistor are 1% or higher precision. I just looked at several, and all of them that use color bands have at least 5 bands.

To the OP: I agree with reheating the solder joint, but for an oxidized joint like that, use a fine wire brush first and extra flux with the solder. If you have access to both sides of the board, do it on both sides.

That could also be a 1kΩ resistor... If it is a bad solder joint, you should still be able to measure the resistance.

It appears from the pics that the colours are Brown, Black and red, with brown closest to the end and red nearer the centre. If that is correct then the resistor value is 1000 ohms.

The 2nd pic seems to show a silver 10% tolerance band after the red, but that may be just the lighting.

A 200 Ohm resistor would see the colours reversed with red closest to the end.

A clearer side on pic of the entire resistor may clear the confusion.

I took it to be red, black and gold...It's a single aaa battery with about a 1.5" square solar collector, powering a single LED...It seems to be high quality with a heavy glass globe...I inherited it, so don't know the source yet....but I guess I'll search it out someday....

If it's red, black and gold with no other colours present, then it's a 2 ohm resistor with a 20% tolerance

Wait there's 4 lines...

Looks like silver, red, black and brown or gold...or vice versa...which would be 1k ohms...+/- 10%

https://www.evilmadscientist.com/2012/resistors-for-leds/

It's a pest when they spread the colours along the length rather than the convention of bunching at one end.

Often the only way to know where to start is by going to the opposite end to the tolerance band.

Some of the later resistors that I use have a blue body which makes precise colour determination all but impossible.

I will stick with my original thought that this is a 1k resistor unless the left colour is grey and the right one gold - in which case it would be 82 ohms 5%, but it looks to be closer to silver than grey.

It doesn't look to be damaged, can you meter it?

Yes I could check it, but doesn't it need to be removed first?....and if I have to remove it, I might as well just change it out....I'm sure I have some resistors laying around here someplace...

If the bad solder joint has lost connection between the board and the resistor, then you should be able to measure the value of the resistor without removing it. Even if the joint has just degraded the contact, rather than isolating it, you should still be able to get a reasonable reading on a low Ohms scale of a multimeter, again without removing it. That resistor looks perfectly fine; no need to replace it. On the other hand, removing it would allow you to do a better job of cleaning the hole and the wire before re-soldering it.

If you use a cheap multimeter you can normally get away with measuring discrete components in circuit as long as there are no obvious discrete paths in parallel.

I've got two (cheap multimeters) here: one (which does have a PP3 9 volt battery) uses 0.26V to measure Ohms; the other which is powered from an LR44 button cell uses about 1.4V.

Neither of these voltages would forward bias your LED, I wouldn't be happy using the 1.4V one on all circuits.

I nearly always use cheap multimeters, and am quite happy measuring components in circuit; I was horrified when I tried to do it with a colleagues Fluke: results were inconsistent and implausible. On further investigation I found that it used 5V to measure resistance. This might make it easier to achieve their stated accuracy, but it forward biases all the protection diodes in sight.

I don't know what other expensive meters do.

I believe you'll find that multimeters commonly use different sensing voltages for different scales.

To me the left band looks more blue than silver, in which case it could be 62 Ohm, 1% ..... put a multimeter on it if you can get a contact at each end to be sure.

Good call, I had totally missed that. The body colour should have given it away as, although I rarely use them, all of the axial inductors that I have are that same colour.

That one of yours would be 51µH 5%, SEs would be 1000µH 10% - big difference for similar applications.

There is normally a larger space between the multiplier and the tolerance bands and, while it's hard to tell definitively, there looks to be a greater space between the 2 at the RHS so maybe SEs colours are grey,red,black and gold giving 82µH.

"The body colour should have given it away..."

Not necessarily. I pulled out a random drawer of 100-300Ω resistors from my collection, and saw about a dozen with a similar body color. Upon closer look, however, I saw that all of the resistors with that body color are precision resistors.

This does illustrate my previous post that the precision resistors use 5 bands of colo(u)r.

Out of interest, may I ask what exactly an inductor would be used for in a module fed by DC sources (solar cell and battery) and supplying an LED or torch bulb? I find simple circuits to be devoid of inductors unless a microprocessor is extravagantly attached.

OK got some more pictures....

There are 3 components....

I think you're right, the smaller one seems to be the resistor(brown, green, orange and gold), the green thing is labelled V1.C, you can see the connection here in detail with the white stuff, looks like flux....

The yellow and black wires on the top are from the solar collector, and the red and black wires on the bottom are to the LED...

"Therefore value = 27 x10 = 270µH +/-20%" in this example...

http://www.learnabout-electronics.org/ac_theory/inductors04.php

http://www.bigclive.com/solar.htm

When I said 1kΩ was high for such devices, I was thinking of current-limiting resistors for LEDs. Obviously that 15kΩ resistor on your unit provides some other function, such as timing or...

Here's the other side of the circuit board on mine:

At top is the battery case; that 02 11 is probably the date code, so this unit has been outside for around 7 years. I'm far from the ocean, and our water is almost entirely snowmelt, so virtually no minerals, and a minimum of chemicals added. Our water is so good that I don't bother drying the car after washing it...

It's really interesting to see how tiny the IC is on my unit compared to yours. The IC on mine has 5 pins; it uses a separate photodetector (the green wires) to decide when to turn on. Just as in yours, the yellow and black pair connect to the solar cell, which produces 2.0V in direct sun with no battery in place, and currently 1.1V (the battery voltage) when the battery is installed.

SMT R1 is the pull-down resistor for the photodetector, with a value of 12kΩ.

It's really disappointing how poor the imported images are, compared to the much sharper originals!

And yours is 1000µH or 1mH

How big is it?

I'd say about .25"...

Brown, Red, Black, silver.... = 12 microhenrys

Then this Bourns one is the closest I can find at Digikey

Brown black red silver: same as yours

1 milli Henry (though they have incorrectly said Mega Henry)

Cost more than the whole light.

I found this about $.09 each...

....er 1 mH...but I don't know the watt rating .25 or .5 .....?

¼Watt will be plenty.

Good luck trying to get anything delivered from India. At least we now know what they really should cost.

I found them for $.06 ea,,, but the catch is you need to buy them in an assortment of 120 pieces....still only $8.00,,, but on the plus side I'll have 10 of them and a bunch of other sizes....

Even though I now know (almost certainly) that the device in question is an inductor rather than a resistor, I still stick by my contention that the device shows no signs of failure. It is only the connection that appears to be defective. Have you tried re-soldering the joint?

Likewise, have you attempted to measure the DC resistance of the device? An inductor this size should measure a few Ohms (including a couple of Ohms of lead and contact resistance), or less. Mine indicated 0.9Ω on the meter (Fluke 116), while direct contact of the meter leads indicated 0.1Ω, leading to the value of 0.8Ω. The only likely mode of failure for the inductor would be to lose contact (break), presumably resulting in a measured resistance of millions of Ohms to Off-scale.

Why buy a replacement for a perfectly good device? You do have a multimeter and soldering equipment, don't you?

Yes I'm going to check it first....will update...

I got ~13 ohms...?

Since your device's inductance is much higher than mine, the wire must be considerably smaller with more turns in yours, so that sounds reasonable.

I was a bit hurried when I made my last reply...

That 13Ω measurement pretty much assures that the inductor does not need replacement; only re-soldering.

Something just occurred to me this morning: most inductors have a magnetic core, while the cores of most resistors are made of non-magnetic materials. Many resistors do have magnetic end caps (as I found out this morning), but with a very small rare-earth magnet, it is quite possible to tell that the magnet is only attracted to the ends of the 1/4 Watt resistors, and not to the core, while the magnet IS attracted to the core of the inductor. Another way to verify that it is indeed an inductor, not a resistor...

I fully agree that SE's existing part is probably OK: so the following is probably moot.

I'm beginning to question my earlier assertion that ¼ Watt would be OK. The Bourns parts I posted a link to earlier have a DC resistance of 70Ω (1000µH) and about 5Ω (510µH).

Bourns 77F102J parts have a DC resistance of 14Ω max, so, would be a better match to the originals. They are 0.4" long.

Now all you need to buy is 119 solar lights you can use the remaining resistors in. This way they don't end up in the junk drawer with all of the other bits and pieces from your other projects.

I would read that as brown black red silver, from right to left in the photo. Which would be 1kΩ with 10% tol. Mainly because that looks silver to me not grey.

I agree. This is a better picture. Silver and gold are only for tolerance.

And if it were the other way you'd be looking at a higher toleranced resistor which is more expensive. I don't know for sure but the solar powered garden lights I've seen tend to be pretty cheap and nasty so I'd guess they'd use cheap components...hence 10% tol resistors.

It's dumpster fodder. They sell these at the 99 cent stores.

Unless it's the only thing you have to worry over, then if it is, keep after it until it's fixed.

I imagine it's breezy there?

It's new to me, not something I would normally buy, but they came with the place, and there's a lot of them....I bought another place inland a few miles...ah the joys of home ownership, so much to fix....Not much wind but it rained for about 2 weeks, greened out the grass real nice, just a week after I replaced the sprinkler pump...(sic)

My wife wants to buy the house next door and rent it out. NO WAY, NO HOW I said. The last thing I want to do is constantly repair someone's temper fits and carelessness.

We have the perfect summer place already, not rented out. Small town in Minn. City Council member cuts and trims the lawn every two weeks, Next door neighbor is the town's exterminator, his wife's sister cleans it for us and her husband does all repairs for me. They all have keys and I don't ever worry about how it looks. We have an account at the local lumber/hardware store and they just bill us when Roger buys repair materials. (they take my checks, too, didn't even want my credit card info)

I never have to do anything except unlock the door and turn on the water heater when we go there. (And that's the way I like it)

Nice setup....but I like to keep busy, that's why I bought it...all these skills need to be exercised....

You could buy the place next door and have a property management company sub out the maintenance. When they call me out to fix the swamp cooler, the property management pays me directly. After everything is paid for, they send you a check every month.

The tenants never will know that the owners live next door.

What's a swamp cooler?

It's the " other alternative " so you too can " go green " .

Surely you jest! Don't I remember that you live a major part of the year in Arizona? That's the perfect climate for a swamp cooler (water evaporative cooler).

Yes, I do know what they are. I've even lived with one for a year., here in AZ.

They are adequate about 3 months out of the year, barring dust storms and humid days. They cause things to rust. Pads have to be changed. Most dribble water onto the ground. (During the summer, even at 10%RH, our AC removes 5 gallons of water every day, from the inside the house and dribbles that too)

Many (most) homes in Arizona do not have natural gas hook-ups or fire places/stoves. We do need to heat houses in the "winter". That's where the heat pump has found a reason for being. Resistance heating is really expensive, so heat pumps fit the dual use role very well.

Just guessing, but I'd say that 99% of the homes built in the valley of the sun do not have swamp coolers. Some homes have dual systems, but I never considered them in the two houses I had built over the years.

Why, everyone knows it's the perfect thing for keeping your swamp cool and crisp.

Can I have the DC market?

Nah, fix it! There is no sense of achievement in chucking it.

& after its fixed, some nail polish remover might stop it happening again -

Nail polish

About failure:

2?'s:

1.Are you on city/ municipal water? If so, there is very small amount of chlorine in it.

2. Is your light in a place that it regularly gets "garden" irrigation spray water? If so, the typical solar lamp is "weather resistant" and not "weather proof"/ water tight.

You would be surprised what long term micro exposure to aqueous chlorine can do.

I am on city water, but I have a well for sprinklers...but, I just bought the place, what went on here before I took possession is an unknown as the pump wasn't working when I moved in, and has since been replaced...

Ah, I see a correlation here. Solar lamp failure, well pump broken. Now a 3thd ?

How much more deferred maintenance have you encountered?

Ockam speaks: The more differed maintenance the more likely the pump hasn't worked for a long time. As you found out water wells and their paraphernalia are expensive items.

Well maintained, but could be better....there's always room for improvement...sometimes a little, sometimes a lot, I strive for perfection, but I'll take what I got....

Maybe this house is built over ancient Seminole burial grounds???

Poltergeist comes to mind.

Sell! Cut your loses, SE!

If the plasma flow is perpendicular to Carol Anne, why does her hair and dress move in the direction of the long axis of her body ?

You'd have to ask the Owl. He is the spirit animal in charge.

This could have something to do with it...

Go buy another light. they are cheap.

oilcan13

That is a 1000 ohm resistor with 10% precision. However, the issue appears to be solder joint corrosion.

BTW, the solder joint is the most likely issue. When jumpered back into the circuit and the light regains operation, spray the board and components with lacquer or other paint coating to keep moisture away from the electronics and it will last for years.

Could it be that the manufacturer has done a timed failure rate analysis, where they have determined the average life cycle before the solder joint corrodes and in turn the customer needs to buy another solar lamp.

Nah! That would take some significant research. In order to sell those things at the incredibly low prices, they simply can't take time for quality control.

How low does the solder level have to get in the soldering machine before adding more solder? "I think we can get one more batch..."

Aha! We have success....after resoldering the joint, and trimming the leg that was sticking out, I put it all back together again,,,and it didn't work....so I took it apart and checked everything again, as usual, my work was flawless...haha So I put it all back together again, and it still wasn't working, but I noticed that I was getting some flashes of the light coming on when I tapped it,,,,but then that stopped....I tried a new battery, that didn't work....So I gave up, and walked over to put it back on the counter....and it came on while in my hand....checked it several times in the closet, working, working working....back in it's holder in the yard, job done....thanks for all the help, one and all....case closed

Excellent, and congrats!

Good result.

Many of these cheaper devices don't use a separate photo cell to detect failing light conditions, they react to the reduced voltage of the PV cell.

Generally, when the PV output goes below 0.7v, the associated IC will decide that it is now getting dark, and will then turn the light on.

Interesting tidbit....

Yeah the batteries go dead occasionally....the system is unreliable...