I currently have a data logger to record temp and RH over
time. It is too late for this season so I am using this time
to gather information and hopefully have something ready for
next spring. The device will be manually set at a start
point just like the current one. I just want the
microcontroller to measure changes in temp and RH and tweak
the interval in real time. I'm not aiming for a fully
automated system as there are too many variables involved.

Allen

-----Original Message-----
From: piclist-bounces@mit.edu
[mailto:piclist-bounces@mit.edu] On Behalf Of Carl Denk
Sent: Saturday, May 04, 2013 9:25 AM
To: Microcontroller discussion list - Public.
Subject: Re: [OT] Greenhouse misting

Not my turf, but I would think the current temperature and
humidity=20
levels need to be recorded, and even think of a sunlight
level detector=20
over a period of time (could be as short as days, or as long
as months).=20
Likely the exact varieties of plants have quite specific
preferences,=20
and the nursery operators will have preferences. Once the
current=20
conditions history is determined, program that as a starting
point, give=20
the operators some manual adjustments of operating
conditions that will=20
be used to fine tune the operation.
On 5/4/13 8:40 AM, Allen Mulvey wrote:
> My daughter and son in law operate a perennial nursery.
> Several years ago I built a misting system for one of
their
> greenhouses. It works fine - all analog, no smarts. A
> misting duration of about two seconds every twenty minutes
> or so usually does the job.  If the weather changes
someone
> needs to manually alter the interval. I would like to make
> another, microcontroller, version which monitors the
> temperature and relative humidity and makes appropriate
> changes. I know there are a lot of other factors involved
> but they have standardized on soil, pot size, etc. so most
> of those are relatively constant. It is gross changes in
> temperature and relative humidity that seem to be most
> important. There is no wind in the greenhouse.
>
> Are there any algorithms or charts available which would
be
> helpful in computing the necessary changes?
>
> Allen
>
>

--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list
archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist


--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.