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Kronos In The Sun

Posted: Fri Jul 13, 2018 7:15 am
by alancyr
I have an original 61 and it has gotten lots of gig use now for several years. Outdoor gigs are a problem if the day is hot, and really bad if it's sunny. The fan is set to automatic and is working. I try to shield the sun the best I can but it stops working just a few minutes after the "fan cooling" light blinks on. I try to keep it unbooted until just before showtime or turn off on breaks. Is it better to cover with a towel to shield from sun or does that trap the heat inside? What else can I do?

Posted: Fri Jul 13, 2018 7:58 am
by voip
The trouble with solar input is that, with solar irradiance being around 1kW per sq metre, an 88-key Kronos will have over 500 watts incoming from the full sun, and the 61-key a little under 400 watts. Quite a bit more than the 30 Watts or so that the Kronos dissipates on tickover. Some will be reflected, but quite a bit will be absorbed, so no surprise that the top panel gets hot, and the electronics below suffer. The best thing would be to shade the board somehow, using an umbrella or similar, or a multi tier keyboard stand with some sort of shade rigged up on the upper level. A towel or blanket would help, provided it doesn't smother the keyboard. The internal heat from the Kronos is lost via the top panel and also comes out in the air flowing out around the keys, and the incoming air also finds its way via the keybed, so keep those clear, if possible.

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Re: Kronos In The Sun

Posted: Fri Jul 13, 2018 8:00 am
by Liviou2004
alancyr wrote:I have an original 61 and it has gotten lots of gig use now for several years. Outdoor gigs are a problem if the day is hot, and really bad if it's sunny. The fan is set to automatic and is working. I try to shield the sun the best I can but it stops working just a few minutes after the "fan cooling" light blinks on. I try to keep it unbooted until just before showtime or turn off on breaks. Is it better to cover with a towel to shield from sun or does that trap the heat inside? What else can I do?
Two points : the direct sun beams, and the heat inside.

As regards the sun beams, the main display of the Kronos is a fragile part of it. It must be protected, one way or another, from direct sun beams.

As regards the heat inside the Kronos, the fan inside is tied to the SSD only. The other components have only passive coolers but no fan. I suppose that a second cooler system should be added inside your Kronos.

Posted: Fri Jul 13, 2018 8:12 am
by voip
Although the internal fan is mounted on the SSD cradle, it does move the air around the inside of the Kronos somewhat, helping to spread the warm air coming off the main processor board and other components. It is actually better to reverse the fan, so that the airflow from it is directed towards the CPU board, since the SSD barely gets warm and doesn't really need cooling. The airflow towards the suction side of a fan is far less directional than air coming from the output side.

Posted: Fri Jul 13, 2018 9:10 am
by Liviou2004
voip wrote:... since the SSD barely gets warm and doesn't really need cooling
A popular belief makes the people think that SSD don't need any cooler. That's not true. SSD can even loose their datas, even if the unit is off and exposed to high temperatures. SSDs need coolers. And the unit (PC, keyboards, so on) do not have to be placed a long time under a high temperature.
That's the reason why I said that it would be a good thing to add a second fan.

The other reason is : the highier is the temperature the slower are the datas transfers.

http://www.jedec.org/sites/default/file ... ode]_0.pdf

Re: Kronos In The Sun

Posted: Fri Jul 13, 2018 12:08 pm
by GregC
alancyr wrote:I have an original 61 and it has gotten lots of gig use now for several years. Outdoor gigs are a problem if the day is hot, and really bad if it's sunny. The fan is set to automatic and is working. I try to shield the sun the best I can but it stops working just a few minutes after the "fan cooling" light blinks on. I try to keep it unbooted until just before showtime or turn off on breaks. Is it better to cover with a towel to shield from sun or does that trap the heat inside? What else can I do?
buy a floor type fan for air circulation on stage. this is a solution by many keyboardists/Kronos owners

Posted: Fri Jul 13, 2018 3:22 pm
by 19naia
Should i have gotten the Platinum editon for better reflectivity?

Was thinking of looks when i got the traditional black.

Would better reflectivity just reflect extra glare back into my eyes?

The other things with internal and external cooling, is there comes a limit to cooling before condensation issues start to happen inside. And that can add up to damage worse than heating.
Really hot and humid areas are best with enough heat inside the board, to keep condensation from forming.
Too much fan per given heat and humity levels or too little fan per given heat and humidity level? At least Kronos has auto and manual fan management.

I lived in a cooler high humidy zone once and would leave my korg on all day to keep internal heat working against internal condensation.
Also moving my kronos from very hot and humid areas to back home in airconditioned environment, allows internal air picked up from hot and humid exposure, to form condensate once moved to indoor cooled spaces. So i like to keep the habit of setting up my rig indoors and leaving it on all day for a chance to build up enough heat to work against condensation inside.

Even more watching to do when i am in parts of Mexico where it gets swings from desert humidity to rain forest humidity. One day can be desert air blowing in from the north and the next day humid air from the south.
So i keep it indoors where it is always cool enough and leave it on for at least 4 hours per session, every day, even if i do not play. Letting it build up internal heat against condensation durng weather swings.

Everything lasts longer in the desert, if protected from high heat. When i lived in Arizona desert, i never had to worry about any of my gear. As soon as i moved from there to tropical hawaii with my rig, it was barely two months before circuitry related issues popped up on the screen and in the function response. Lost Synths, TV’s, gaming consoles like that.
Things changed when i started leaving my electronics on all day.
Never letting humidity get a full 24 strectch without my stuff turned on and fighting back with internal heat.

Seems off topic here, to support heat in the device. But it is just stuff to remember before getting consumed by the idea that cooling and cooling and cooling is all that matters. In the original post conditions, yes. Cooling as needed but not too much. And too much is relative to humidity in the air that is flowing in and out. And when the device gets moved? Or plays on a cooler day without direct sun? Is cooling going to do any good especially if the air is humid but not hot enough to bother the device function?

Sun shade and a huge-wide brim Sombrero hat is always my first suggestion. Ok Maybe Sombrero is not the look.
But a system-down kronos is not the look either.

Posted: Fri Jul 13, 2018 4:29 pm
by Bachus
Instead of a top keyboard, buid a sunscreen around the kronos... make sure there is airflow between the kronos and the sunscreen...

You can allways put your 2nd keyboard on top of the sunscreen.. if atleast that keyboard can handle direct sun...

Re: Kronos In The Sun

Posted: Fri Jul 13, 2018 7:42 pm
by Phinnin
GregC wrote: buy a floor type fan for air circulation on stage. this is a solution by many keyboardists/Kronos owners
This!

Posted: Sat Jul 14, 2018 12:25 pm
by AntonySharmman
Voip was very clear at his observations ...
You have over 0.5 Kw of heating absorption strength power applied on the fully absorbing black mat surface of Kronos under full sunlight !
Even a 300W turbo fan can't dessipate this temprature under 40 degrees of Celsius and also ultraviolet radiation will gradually destroy LCD ,
plastic tabs & surface letter fonts of interface ...
The only solution for under direct sun gigs , is a suficient reflection shader above keyboards gear !!!

Posted: Sat Jul 14, 2018 3:18 pm
by voip
Posted below from another thread at: http://www.korgforums.com/forum/phpBB2/ ... hp?t=96575
voip wrote:I changed the fan to a much quieter version.

The keyboard housing never gets much warmer than about 30 degrees C.

Here's a thermal infra red image of the board after several hours of being powered up and played.

https://app.box.com/s/n8vgsb0mg3vab757ek0nsc5iosa5ryaa

..
DJ Kronos wrote: It's not surprising that the hottest area is near the transformer & PS.

I have an X88 and while I don't have an exact reading, my fingers tell me that the surface seems to remain cool (about the same as yours.)

My internal temperature is usually around 60°-65°C with a room temperature of 25°C, but that's with the fan on full as it used to be before the V3.0.2 upgrade. I'm too chicken to turn the fan down. I'm also waiting to see what happens when the summer comes and it's 30°C or more in the house.


drdave2002 and LivePsy, you've both said that your boards get as hot as 80° to 82° C. Have you let them run at those temperatures for a long time? Do you know what the temperature was when you got the warning message? It would be great to know what the "safe" limit is.
..
voip wrote:The fan was fitted some time ago and I'm pretty sure the airflow direction is from right to left making the keys on the left side of the board warm from the warm air plume coming out, whilst the keys to the right hand side are cool because that's where room air is being drawn in. Most of the heat comes from the motherboard. The CPU heatsink stays relatively cool, whilst there's a chip nearby (graphics possibly?) that does get rather warm (guessing ~70 degC) and doesn't have a heatsink, although I think it should. The SSD barely gets warm.
..
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Re: Kronos In The Sun

Posted: Sun Jul 15, 2018 3:45 pm
by benny ray
GregC wrote:
alancyr wrote:I have an original 61 and it has gotten lots of gig use now for several years. Outdoor gigs are a problem if the day is hot, and really bad if it's sunny. The fan is set to automatic and is working. I try to shield the sun the best I can but it stops working just a few minutes after the "fan cooling" light blinks on. I try to keep it unbooted until just before showtime or turn off on breaks. Is it better to cover with a towel to shield from sun or does that trap the heat inside? What else can I do?
buy a floor type fan for air circulation on stage. this is a solution by many keyboardists/Kronos owners
Last time I played outside I used a floor fan for circulation fairly close to the Kronos and never had a problem knock on wood.

sun and lcd screen

Posted: Thu Oct 11, 2018 3:40 pm
by GrahamBanks
I have played quite a few outdoor gigs in the 80s or a little above and have had no problems with overheating.

However, glare on the screen has been very troublesome. I can't even make out the patch names in some circumstances. I build a small deflector to try to shield the screen, but even the indirect bright sunlight washes out the screen.

Has anyone found a good solution to this?

Re: Kronos In The Sun

Posted: Thu Oct 11, 2018 3:57 pm
by leonh
Phinnin wrote:
GregC wrote: buy a floor type fan for air circulation on stage. this is a solution by many keyboardists/Kronos owners
This!
Yes this