Use a waterproof box with a plastic cable gland to hold a piece of “perspex” rod.
The uv board is held in place by some hot melt glue, with the sensor positioned so that it is flat against the end of the rod.
If you look down the rod you can see the sensor quite clearly.
The rod was from ebay 10mm in diameter. The ends must be flat. I polished mine with metal polish arbour in my drill.
Brasso is also worth a try.
See pics
Does it work? Most Perspex/acrylic/plexiglass doesn’t transmit much UV.
It works, getting max reading @ 14:00 of 2.3
The UK met office forecast 2 (no decimals).
Will continue to test. The Acrylic rod could be shorter, my also try to source rod the has a better UV transmission.
Cheers
Peter
UV transmission will of course depend upon the grade of perspex used but I would not think this would be a problem. UV transmission figures I have seen suggest that UV transmission through Perspex is of the order of 75 - 90% plus at UV wavelengths between about 350 and 450 nanometers. However, reducing the length of the “light path” by reducing the thickness/lenth of your perspex rod would be a good precaution.
Cheers
Rob
Hi Rob,
I did a bit of a search and found that the perspex used in “Tanning Beds”, (This is the UK!) has excellent transmission of UV. But it only comes in sheets.
The piece of rod I got was a sample, so cant complain too much if it isn’t ideal:)
A good set of readings should show how good it is.
Cheers
Peter
Peter,
I came across something similar with reference to perspex used in tanning beds myself. If your rod sample is made of the same stuff then you should be ok. From what you posted earlier your results show you are on the money.
Given I am in Australia with the harsh sun out here I should set up a 1-wire UV sensor myself. I presume the one you set up is a Hobby Board unit?
Cheers
Rob
Rob,
I do have the HB sensor, I did have to return it to HB as I could not see the ROM Id, yet alone any readings:).
Its now mounted along-side the Solar, but not yet on the above roof in a “clear all day” location.
Peter
Hi,
Do you have more recent experience in the assembly and the measurement?
Hi Zoltan,
What info do you need.
Box mounted on a pole see photo.
Readings seem too low, Max is 2.0 but Met office says 4.0
Cheers
Peter
Hi Peter,
The instrument accuracy is very important to what the substance is on the sensor.
In practice, our experience has shown the accuracy of the measurements over an extended period of time?
I have already ordered the fiberglass rod… I just do not know, a good measurement?
bye
Zoltan
