Topic: any suggestions buying davis 6152 from ambient vs scientific sales

[tom03087]

I am about to buy my first station. I have settled on a Davis 6152 with the 6510USB addd on. Based on price these 2 are very close. Ambient I understand offers their software with the purchase. Is that worth while? Any other pros or cons between the 2 suppliers? Last question anything else I should be adding for my initial purchase? Thanks for any help you can offer a newbie.

[Garth Bock]

Welcome and congrats on your choice. However, do the serial data logger and not the USB. Some people have luck with it not dropping connection and some do not. VWS is excellent software compared to the others and I have almost tried them all. The support from Ambient and Davis can't be beat. Depending on what you want to do will drive what you need to buy. The solar sensor is good for monitoring evapotranspiration for watering lawns and gardens. Buy what works for you. Believe me there are plenty of folks here that will help you spend your money. LOL. I started with just the ISS and bought an Envoy so that my console (when I buy it) will not be tied to the computer all the time. I am adding solar and the sensor shelf first though. Take it slow. Plenty of time to build a great weather station as you learn how its done. Don't be afraid to ask for help here. Lots of folks here that are happy to help.

[tom03087]

Thanks for the thoughts. I went ahead and ordered from Ambient. I changed from the USB version to the serial version as you suggested. Now I just have to get it all set up when it arrives.

[Sigdigit]

Garth, when you get the solar sensor (much cheaper than the UV sensor by the way, which I really have no use for) you can make your own mount very easily. Mine is constructed from two small 3x3 inch squares of plywood painted white, held together by a hinge.  This allows me to "aim" the sensor at the sun at solar noon and easily make adjustments throughout the year.  This allows for the most accurate "real feel" temp on the human body, or as Davis refers to it, the THSW index.

[Garth Bock]

I didn't think about sensor re-orientation due to sun angle. Interesting idea. Hmmmm. The sensor has a level bubble on it so that is shoots straight up. Does shooting it at an angle and not level disturb or improve it's reading ?

[Garth Bock]

Thanks for the thoughts. I went ahead and ordered from Ambient. I changed from the USB version to the serial version as you suggested. Now I just have to get it all set up when it arrives.

Cool. If you have any "howzitdone" or "howdudoothat" questions you will find everyone very helpful here. Always take it in steps (unless you have the cash to buy it all). I am finally ready to launch my website. There is still some testing and juggling of the look. One neat feature I have is my online weather quizz game. Don't let yourself get overwhelmed by all the neat sites out there. Took me time to find what I wanted to present.

[NiceBill]

Garth, when you get the solar sensor (much cheaper than the UV sensor by the way, which I really have no use for) you can make your own mount very easily. Mine is constructed from two small 3x3 inch squares of plywood painted white, held together by a hinge.  This allows me to "aim" the sensor at the sun at solar noon and easily make adjustments throughout the year.  This allows for the most accurate "real feel" temp on the human body, or as Davis refers to it, the THSW index.

Interesting, why do they put a bubble level on the solar and the UV sensor??

Bill.>>>>>>>>>>>>>>

[Sigdigit]

As far as tilting the sensors, I found this from a Davis document:

✦ For evapotranspiration (ET) or scientific measurements, the sensor can be mounted on the Sensor Mounting Arm (SMA) or any level surface.
✦ For measurements where the immediate effect on humans is of interest, we recommendthat you mount the sensor such that its axis is aligned with the sun’s rays at solar noon.This will maximize the mid-day readings and provide what is probablya more accurate measure of the solar radiation people are exposed to.
The Health EnviroMonitor™ calculation of the solar radiation contribution
to apparent temperature assumes that the sensor is tilted. The Sensor
Tilting Bracket #7706 is designed for this purpose.
✦ Similarly, if you wish to predict or monitor the irradiance on a solar voltaic or
thermal collection panel the data are probably most relevant if the sensor is tilted
to the same angle as the collection panel.
The Sensor Tilting Bracket #7706 is designed for this purpose.

As I am currently most interested in the "human exposure" aspect of the radiation readings, I have mine aligned with the sun at solar noon.  My peak readings are pretty high on a clear day.

[NiceBill]

It would be very interesting to see the difference between the straight up mounting and the angled mounting.

If it is that great, I for one will walk with a straighter posture, as a posture at an acute angle could be hazardous to the top of ones head. 

Bill.>>>>>>>>>>>>>>

[Mark / Ohio]

...
If it is that great, I for one will walk with a straighter posture, as a posture at an acute angle could be hazardous to the top of ones head.  ....

That's why as the shingles thin it is well advised to wear a hat.   

[NiceBill]

The shingle is like new, I just keep the lawn mowed like a putting green.

Bill.>>>>>>>>>>>>>>

[Mark / Ohio]

The shingle is like new, ....
Bill.>>>>>>>>>>>>>>

Some of us (read me) are not as genetically well blessed.   

Mine apparently were only guaranteed for 30 years.      

[WeatherBeacon]

I believe that typically the sensor would be mounted horizontally (subsequently the leveling bubble). The reason is because physical quantities like water evaporation rates (lake water, for example), evapo-transpiration rates (from vegetation), melting rates of snow and ice, sublimation rates of snow and ice, etc., depend in part on the solar power (measured in W/m²) that is incident on the surface of the ground. The solar rays are more direct in the summer than in the winter; they are more direct near the equator than near the poles; and they are more direct in the afternoon than in morning or evening, for examples.

             Incidence
    Direct                Indirect
 12 rays/m²           7 rays/m²

||||||||||||         \ \ \ \ \ \ \
__________          __________
    1 m²                    1 m²

As another example, unlike a sunflower that orients itself to face the sun throughout the day to maximize its absorption of solar power, the surface of the ground (or of a lake) does not orient itself to directly face the sun. Thus, it is usually more natural to measure the solar power incident on a horizontal plane and consequently, to level the sensor horizontally.

Isn't the sensor shaped like a fish-eye lens? I believe the sensor also measures diffuse light, according to NOAA, "for the entire hemisphere" (meaning the entire sky above). If so, then mounting the sensor non-horizontally would not measure all diffuse light from the sky (since part of the sensor would be viewing the ground).

But hey, whatever floats your bubble!

Regards,

Kevin...

Reference:
   http://www1.ncdc.noaa.gov/pub/data/uscrn/documentation/site/sensors/solarradiation/Descriptions/summarycurrentsolarradiationsensor.doc

[NiceBill]

Thanks Kevin,

That's a great answer to my question in post #6.  With regard to your reference, wonder what that solar sensor cost??  Behind the sensor is a rain gauge, one with a wind fence, not often seen, I am in the process of constructing one, for one of my 8" rain gauges.

Boy, did we hack this thread or what.

Thanks for posting,

Bill.>>>>>>>>>>>>>>

[tweatherman]

Just curious Bill as to many 8" rain gauges you have.

Tim

[NiceBill]

2

Bill.>>>>>>>>>>>>>

[Garth Bock]

Solar sensor is on the way with mounting shelf. Website is up and running so far..now I can sit back and tweak it. I am now shopping for a wireless PTZ. I have put together most of the hardware for a solar power station so the camera will be totally wireless.

[Garth Bock]

The shingle is like new, ....
Bill.>>>>>>>>>>>>>>

Some of us (read me) are not as genetically well blessed.   

Mine apparently were only guaranteed for 30 years.      

A friend of mine use to sun burn the top of his head on purpose....I asked why and he said so that when it peeled everyone would think he had dandruff...lol.....