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Casio Solar Charging (Tough Solar) and Power saving

11065 Views 11 Replies 6 Participants Last post by  heyjudek
Hello everyone. I own several Casio watches with the Tough Solar feature.
- STL-S100H-1AVCF
- W-S220-1BVCF
- LCW-M100DSE-2AER
- GW-S5600-1JF

As you know, there is a power saver feature on these watches where the watch display goes off (in the case of the LCW-M100DSE-2AER, the second hand also stops) and will be turned back on if any button is pressed or a watch is exposed to light.

I can take any of these watches to a bright area both indoors and outdoors (No sun, the sky is basically white but one can comfortably do any task requiring light such as reading) and the face doesn't turn back on unless I face them to a direct light such as full sun or a desk lamp.

My question is this, since Tough Solar watches are supposed to be charged from any light, does the fact that the watch display doesn't turn back on mean it is NOT charging?
I hope that is not the case.
Please excuse my ignorance on the matter.

Thanks a lot :)
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I think it charges anytime the solar panel is exposed to light, it just absorbs it and charges the battery

Power saver is a different, unrelated function of the system and does not control input. Power saver controls output of the battery.

Tough Solar - Technology - Watch Technologies | CASIO
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Thanks for the info.
I got WS220 recently and it shipped with the charge on M and for a week I wore it around indoors and outdoors just wasn't sure whether it was charging. But putting it face to face with a 10W lamp brought it to H in less than an hour.

I was kinda confused about many people complaining about solar watches on amazon and sometimes on WUS. For me, no complaints so far ;)
it takes a certain amount of light to activate, or pressing any button activates. as for charging any light will due but the more intense the faster the charge.

my GW-M500F activates with motion.
I have bought seemingly totally dead solars on eBay several times for dirt cheap. I put them in my windowsill and every single solitary one has recovered to H every time. Sometimes it takes a week of sunlight, but they always wake up fully.

I have never had to change a solar battery in any of my dozens of solar watches

Complaints on Amazon are meaningless.

One of my 4 window sills full of Solar watches charging

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it takes a certain amount of light to activate, or pressing any button activates. as for charging any light will due but the more intense the faster the charge.

.
Except car dashboards, where the watches can be damaged and sometimes parts will melt. Too hot.
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Except car dashboards, where the watches can be damaged and sometimes parts will melt. Too hot.
True, but that isn't light intensity causing heat, that's greenhouse effect.

Sent from Capt Kirk's communicator
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My question is this, since Tough Solar watches are supposed to be charged from any light, does the fact that the watch display doesn't turn back on mean it is NOT charging?
I hope that is not the case.
Please excuse my ignorance on the matter.

Thanks a lot :)
For I know, Charging and PS mode operates after the other, they cannot be operating at the same time. PS mode goes when there is no light between 10PM and 5:59 AM and it will not operate between 6AM and 9:59PM unless it is already operating before 6AM. PS will automatically cut whenever it recognizes a certain intensity of light, which eventually give way to the charging process.
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Well it is given that the cell would recharge even in low light.
I once put my tough solar watch in windowsill overnight which made it go to Power-Saving mode since it was absolute darkness. However when it was morning and there was full light (just no direct sun, it was a fully white sky) the watch was still in PS mode. But if I held it to a much more direct light, such as facing a lamp it will wake up immediately.

Would I be right to assume that in a working mode it would recharge with any light but the light necessary to wake the watch is WAY stronger than what it needs to make it recharge?
So once it goes to PS mode it should wake up first to start charging with any light otherwise unless the light is strong enough, it will stay in PS mode and not charge?
I keep all my solar atomic watches face down at night (for some reason they generally only receive in that orientation) and they go into power save mode. If I just turn them over and expose them to the low inside light, they will take some time to "wake up" but they will do so eventually. Otherwise if I tilt the watch back and forth, or shake it, the display comes right up. I'm not entirely sure why that is, but it works. Or, as you mentioned, you can just push a button.
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Otherwise if I tilt the watch back and forth, or shake it, the display comes right up. I'm not entirely sure why that is, but it works.
It's because most Casio models that have a "power saving mode" or "sleep state" also have "auto EL," which is triggered by a tiny gravity powered switch inside the watch -- turn the watch a certain way towards your face to read the time, and the switch makes the light comes on (if the solar panel also decides the room is dark enough to need the light) and/or makes the watch "wake" from "power saving mode."

Would I be right to assume that in a working mode it would recharge with any light but the light necessary to wake the watch is WAY stronger than what it needs to make it recharge?
So once it goes to PS mode it should wake up first to start charging with any light otherwise unless the light is strong enough, it will stay in PS mode and not charge?
Probably a good guess, but extremely dim light isn't going to be enough to charge it appreciably. Normal indoor florescent lighting is going to take about 90 times longer than sunlight to accomplish anything, and the dimmest of lights is probably barely going to "break even" against Casio's estimates of "normal battery use." Here's the chart for the GW-S5600:

Text Font Line Number Document


I just charge my solar watches outdoors, in the sun, when they drop to "medium" or below. It's important to note that in any of Casio's charts, the largest number in a given line is "how long it will take to charge the watch from the bottom of 'medium' to the bottom of 'high'" and the last number in a given line is how long it takes to charge the watch from "the bottom of 'high' to 'fully charged.'"
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I see. I am aware that indoor lighting would be an order of magnitude less efficient in charging. But what surprised me is that on a cloudy day the watch wouldn't wake up from power saving but considering it was already in an active mode it would recharge right? It seems the required amount of light to "wake" the watch up is much higher than the amount of light intensity it needs to recharge.
Otherwise, I find it weird that the watch cannot be charged on a cloudy morning just because there is no direct sun.
I wish CASIO would incorporate something that would show if the watch is currently receiving charge and how much but I guess this is as much as asking for thermocompensation :)
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