Topic: Regular radiation shield into 24 hr. fars

[tweatherman]

I was just curious if there's anyone out there interested in looking what I have done to make make a standard davis shield into a 24 hr. fars. The project is a little costly but I will not get no temp. spike at all with the fan I will be using. Will take picks and expalin if anyone is interested.

Thanks,
Tim

[WestMichigan]

You say it is costly.  How costly?  It sounds interesting.

[tweatherman]

The cost around $85..involving a12v battery and solar panel to charge the battery to operate the 12v fan.

Tim

[wuhu_software]

The cost around $85..involving a12v battery and solar panel to charge the battery to operate the 12v fan.

Tim

I am interested in the details of your setup.

How many milliwatts does your fan draw?

Thanks.

[MesquiteWx]

Well for that price why don't you just spend a little more and go all out and get the 24hr FARS?

[Anthony]

Because the 24 hour FARS is not an add on option. It has to be purchased as a weather station package option. You can however add the day time FARS.

[Anthony]

tweatherman,
Why not post a list of materials and some pics (if possible) of your design? I'm sure there are other davis users that will find them useful.

[tweatherman]

Anthony,
I will provide list of materails and some pics this weekend. I've been busy this week with father-inlaw in the hospital and six kids at home. The fan only draws 1 amp. of power.

Tim

[andro700]

That would be great. Always wanted to have a 24 hours aspirated fan. Did not know about it when I first purchased my Davis back in November of 2005. A lot of nights here where the wind is calm. It will help with more accurate temps and humidity as well.

Thanks,
Chuck

[MesquiteWx]

You couldn't use a lesser powered fan maybe? 110 watts that is a lot of power for something so simple. You could probably cut cost and power if you used a lesser fan. Just a thought.

[Anthony]

Have to agree, 1 Amp is alot of power for a 12 Volt fan. I have several fans lying around that only draw about 650 mili amps. Are you sure it's 1 Amp and not .1 Amp?

[WestMichigan]

The Davis 24-hr fan unit uses rechargeable NiCd batteries with 1 or 2 C Cells per unit.  This would not support 12V @ 1 amp for very long.  THey have to be using a much lower rate which would make the design considerably cheaper I would think.

[wuhu_software]

I have a ton (literally hundreds) of .13amp 12VDC brushless fans but would like to find fans that consume much lower energy.

Does anyone have a good source for micro-fans that can be directly driven from a low-power solar cell?

I saw that commercial for one of those auto-fans with a small cell like this:

http://insight.fungiart.com/solarfans.html

Harbor freight also sells a solar cell with batteries for sheds, $20, apparently it has 4 AA rechargables, supplying 6VDC right in the panel:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95573

Combined with a low-power fan, it would be a nice setup.