Topic: FARS in the Winter

[Aardvark]

we had 4 inches of snow yesterday, covering up the solar panel to the FARS. So when I went out to the station to brush the snow off the UV/Solar sensors, I noticed that the solar panel had snow on it, which I cleared and then noticed that the fan wasn't working.   

I am guessing that the batteries exhausted themselves as the panel was covered yesterday, not much direct sunlight, well none to be exact.   Today it  will be cold, sunny and no snow, so we should get some charge as well as running the fan and it will take a lot of days to recharge the batteries.

Something to consider when placing a VP2 station , access to solar panels that do get covered in snow.

[BigOkie]

we had 4 inches of snow yesterday, covering up the solar panel to the FARS. So when I went out to the station to brush the snow off the UV/Solar sensors, I noticed that the solar panel had snow on it, which I cleared and then noticed that the fan wasn't working.   

I am guessing that the batteries exhausted themselves as the panel was covered yesterday, not much direct sunlight, well none to be exact.   Today it  will be cold, sunny and no snow, so we should get some charge as well as running the fan and it will take a lot of days to recharge the batteries.

Something to consider when placing a VP2 station , access to solar panels that do get covered in snow.

I noticed that as well, but my fan was running.  I had about 1" of snow on the fan panel.  We have another chance of snow today.  I've been checking the panels periodically for snow.

[dj1111s]

As my wife shook her head and rolled her eyes I just ran out in the bitter cold with her rubber clogs on (the ones with holes in them) (bare feet getting full of snow) (no coat on) (did I mention it's really cold out) to check my solar panels.    Everything is clear and the fan is running.

[cospringswx]

As my wife shook her head and rolled her eyes I just ran out in the bitter cold with her rubber clogs on (the ones with holes in them) (bare feet getting full of snow) (no coat on) (did I mention it's really cold out) to check my solar panels.    Everything is clear and the fan is running.

That is dedication right there.

[Aardvark]

an international hero, yesireee

[Cienega32]

Dedication or a lack of enough shoes...

[SlowModem]

As my wife shook her head and rolled her eyes I just ran out in the bitter cold with her rubber clogs on (the ones with holes in them) (bare feet getting full of snow) (no coat on) (did I mention it's really cold out) to check my solar panels.    Everything is clear and the fan is running.

I'll bet it was uphill both ways, too!   

[dj1111s]

It was uphill one way. Dedication yes.  A bit crazy? nnnnnnn,...yes.  My wife is used to it.  At least I didn't go up on the roof to shovel a path to the anemometer.

[Aardvark]

you know  that you have sparked my interest to venture outside now and check , in the dark , slick as heck if the dang thing is running or not.  I can see it now, they find me  frozen like a dead moose in the yard with rabbit turds on me  out by the ISS in the morning.

[BDL69]

performance issues aside, does having snow on the sensors do any damage to them?

[Aardvark]

snow on the sensors inside the shield?  yes.  Humidity would be off, probably very close to 100% within tolerance limits and the snow temperature could be 32F or less.  You want to make sure that the shield is set so the risk is minimum. IF they are mounted correctly in the radiation shelters. then you are safe.   Now I would guess that if snow or freezing rain actually filled the shield then maybe the .readings particularly the humidity would be giving false readings until they dried out.

Now my FARS is according to sitting specs "The standard height above ground for a thermometer hygrometer is five feet (1.5 meters)."

I would venture a guess that there is a remote possibility that a radiation shield being up higher, such as a roof mount which wouldn't be at the standard setting could get an updraft pushing water up into the shield through the vents and that could have an effect.

However,  I have always been careful to make sure that my station is sitting correctly and I can feel comfortable that my conditions are those at my site are correct for my site location.

[BDL69]

Thanks for the info Aardvark.

[dj1111s]

Went out to look at the station after the snow let up to find both solar panels completely covered with snow.  And considering there hasn't been any sun in a while I listened for the fan and there wasn't a sound.  Wiped off the snow then listened again and the fan started to spin slowly.  Mind you it's still completely overcast but the panel is picking up some energy.  If a person were to look at their solar sensors would it be the solar radiation that is giving my station its energy?

[Aardvark]

yes,   For the past couple of days, it has been cloudy  and the batteries depleated.  We had about 6 inches of snow, and my panels were covered, as soon as I moved the snow off the fan started up and the thing should start recharging the batteries.  If you are getting some solar radiation it might be charging, but bright sun does the trick.  I am  at 460 w/m2  and it is charging.   

[dj1111s]

I am only at 90 w/m2.  High was 237.

[Aardvark]

a lot of that has to do with sun angle, in the winter it isn't going to be as direct overhead.  If the sun is out, then the panel charges.  I am measuring the passive temperature vs. the FARS,  it is about a degree warmer and 1% more humid than with the FARS.   Fars is better in the Summer when the temp and humidity is not as much fun

[dj1111s]

Went out today to look at the console and the fan is not spinning with direct sunlight on the solar panel.  My fan always made some (call it unusual) noise but I had nothing to compare it to so I figured it was normal.  Could the fan have died?  I have not taken it apart yet as I am busy tonight.  Will be a Saturday project.

[Aardvark]

how long have you had the fan?  Davis recommends replacing them every 3  years, I believe.

My first thing to check is the solar panel that it is connected, that the wires are not broken or frayed (i.e. shorting).
Next I would go for the batteries, they are 1.2 nicads  and finally the fan.

The real pain in the tush is that you have to remove the FARs from the bottom . I'd go with the nicads being bad, but a new fan from Davis is 45 dollars,  I'd shop around.

You can always call Davis or email them

[dj1111s]

how long have you had the fan?  Davis recommends replacing them every 3  years, I believe.

Since last July so less than a year. If the fan is bad it should be under warranty. I'll take things apart Saturday and check out various things with a volt meter.

Just want to get this fixed before it starts to get warm out. I probably have until late August then to fix it. 

Thanks

[dj1111s]

And it has been a very unsunny winter this year with a lot of subzero days.  That's got to be hard on the batteries.

[ValentineWeather]

I believe even with dead batteries the fan will still run with solar. Just turns into a daytime only FARS. Something wrong besides the batteries I suspect.

[dj1111s]

I believe even with dead batteries the fan will still run with solar. Just turns into a daytime only FARS. Something wrong besides the batteries I suspect.

Thanks, my thoughts as well.

[DaleReid]

My computer has a gizmo in the fan circuit that tells me the rpm of the cooling fans on the processor.

I take it from the comments here that the FARS doesn't telemetry the running/stalled/not running condition back to the console?

I'm amazed at watching the telemetry back from the Rainwise unit on the voltage coming off the battery.  Even with a couple inches of snow on the panel, I usually get a higher voltage than the night time battery reading. 

As anyone tried RainX or that new 3M slippery stuff on their panels or will that fog or craze or ruin the surface?

[Aardvark]

My computer has a gizmo in the fan circuit that tells me the rpm of the cooling fans on the processor.

I take it from the comments here that the FARS doesn't telemetry the running/stalled/not running condition back to the console?

I'm amazed at watching the telemetry back from the Rainwise unit on the voltage coming off the battery.  Even with a couple inches of snow on the panel, I usually get a higher voltage than the night time battery reading. 

As anyone tried RainX or that new 3M slippery stuff on their panels or will that fog or craze or ruin the surface?

The Davis FARS gives minimal information other than weather parameters and reception at the console/Envoy.  The circuit is simple, solar panel, battery, fan.  I still would check out the solar panel wiring. If you can put a meter on the panel, you should be fine.  I'd make sure that the fan blades turn and then get a new fan motor.   

[johnd]

Maybe it wouldn't be too difficult for a simple, low power circuit to pick up the fan RPM somehow and convert it to a 0-3v signal, which could then be use interfaced to an unused 3v input on a VP2 SIM (eg the UV input will often be unused) and then picked up on an Envoy8X.