Hello all. I am something of a tinkerer and have many hobbies. I would like to design a piece of hardware to control the microclimate in a small greenhouse. Essentially it would control a series of humidifiers and in the future a heater.
Now when I say I have no experience in electronics that means I haven't touched a breadboard since middle school in 99... I understand some basic principals but as far as selecting components or designing a schematic? Clueless.
If anybody has built something like this, or could point me in the right direction I would be very appreciative.

Happy New Years!

 

First off, define the interfaces.

i.e. how many inputs? what type of inputs are they; analogue/digital? What currents and voltages are involved? How many outputs? etc....

 

It sounds like you likely would want a computer or microprocessor to control everything.

 

I think a small PLC would be most suited to this application.

 

I would like to design a piece of hardware to control the microclimate in a small greenhouse.

That's fine, but there are commercial systems for doing this. Doing one yourself will take time and possibly cost more than just buying one. Again, that's fine as long as you're fully aware. Reverse engineering the major functions of the commercial devices may simplify your design.

If your heater is electrical, as opposed to gas, that will likely be your highest power load to control and you should design with that in mind; size your relays large enough to handle that load.

 

I've been controlling the temperature and humidity in whole houses and small factories for 40 years. Buy a thermostat and a humidistat and wire them to your heater and water source.

Then again, you said you want to design a piece of hardware.
OK. You can start by designing a thermostat. When you get done with that, work on the humidistat.

 

I think a small PLC would be most suited to this application.

In the form of a Smart Relay maybe?
Max.

 

In the form of a Smart Relay maybe?
Max.

Exactly, something like this:

http://www.schneider-electric.co.uk...cro-plcs/programmable-relays/zelio-logic.page

 

There are quite a few out there, some appear to be just relabeled.
Omron, Idec, Siemens, Sneider, Some will offer the S/W free, but almost all can be programmed from the front buttons.
A nice feature is they usually include a 24hr clock.
Max.

 

The Zelio software is free and includes a simulator. It's very easy to use and anyone can start programming with it almost immediately.

 

I am something of a tinkerer and have many hobbies. I would like to design a piece of hardware

If you're simply looking to solve a problem then some of the items discussed above will help. However it sounds like you want the challenge of building it yourself, rather than simply solving a problem. If that's the case, then you're only taking the first step of a very long journey - and I doubt anyone here will be able to walk you through that.

Many people start using microcontrollers as they're pretty easy (relatively) to program logic into - take a look at www.arduino.cc and some of their resources. From there... Google is your friend, I'm afraid.

 

One advantage to the Smart Relay is the I/O is already conditioned for P.B. input and relay output.
The language has a shorter learning curve than Micro's if one has never used a micro before.
Max.