Greenhouse / Propagator heating control

Hi,

Its starting to get colder at night and apart from the basic heaters / propagators some form of temperature control is usually needed and there are many such devices around typically to control just one device.

I have a small heated enclosure for orchids etc and also keep the greenhouse just frost free with a fan heater and use some small electric propagators in the spring, so having a single controller to handle everything does simplify things.

Just finished is my own Arduino based controller which temperature controls 4 devices and records min/max temps as well etc. ( a test version has been running most of this year in the greenhouse without fault)
Its nothing special, but does show that even us oldies still have some brain cells left to write the odd line of code.

 

Hi @ricky101 - nicely done! I assume you had some relays for switching the power inside that case? How did you waterproof it? (Or are you more careful than I would be...)

 

Hi,

Well as I found from my experiences of doing a fish tank controller some years ago you have to draw the line at just supplying details of the the low voltage dc circuitry.
Give any info on the mains electrics side of things and you could become very liable !

I know lots of folk do give out such info, but always feel I would be the one caught out and do not want to loose my house and home to the solicitors etc !

With doing the fish tank controller I found using solid state relays cause less interference when switching than mechanical relays, but of course they do not isolate in the same way as a mechanical one.

Again , as you suggest, keeping things safe from water / excess humidity is essential.

Just been doing a simple connection diagram of the Arduino board you might be interested to see.. you can buy clone boards so cheap there days, its not worth building you own from chips.

Not shown in the photo above is the use of a humidity sensor, an outside temp sensor, RTC module and future provision for watering timers etc come next summer.
Have a couple of i/o lines spare so still thinking about using a little Sim900/800 module to send a message/ring out should a temperature alarm situation occur.

Assume you have something similar already in your greenhouse ..?

 

Hi,

Have had the program running ok for a week or so and all seems good and am monitoring things from the PC as the screenshot below shows with todays reading.

Its just the basic heating control over 24 hours, still got to add things like previous days min/max and heating cost / usage etc.

If anyone is using Arduinos and wants to try the code, it will work on without any sensors etc, just returns a 0c readings, but it does let you see how it runs via the serial monitor.
However you will need to pm me with an email address as cannot upload a .ino file on this forum.