Some of you might have read about one of our members looking for beta testers for a PLC he designed to be used for homebrewing, I was one of three selected to do a beta for him… and will post my findings as i experiment along the way.
I had to understand the concepts of State Machine programming and it did not take too long surprisingly as I haven’t done anything like this since Uni, almost 25 years ago.
OK, so the unit arrived Wednesday from Embedded Control Concepts and I finally got to play late Saturday night.
http://www.embeddedcontrolconcepts.com/ for more info.
The owner has agreed to let me post my experiences as I go through them and I will also add these to my blog.
The unit is packaged into a Black 6×4x1″ Alu container,(Pics to follow)
The I/O is all on one side - very neat for a beta box.

First out - the Ethernet port is self sensing , and even if directly connected does not require a cross over cable (I spent 30 minutes looking for the one I know I have and never found)
The system will auto fail to DHCP and self assign it’s own IP address after 20 secs if directly connected.
I tried networking it through my wireless router and had no luck finding the assigned IP address, (I later found out the WIFI router has a table of all asigned addresses and I could have looked it up - DUH)
I had to force my Local Connection ethernet port to a fixed IP in the end, as the WIFI kept setting its IP config to same as WIFI. This is something that will be looked at during the beta. I will also attempt to look at connecting this to more than one PC to see how easy / difficult the first connection is. We will also look at using a WIFI Print router to connect it remotely, but this will be later on.
The external items needed and sold on the site are the Immersion temperature probe, 10K ohm NTC thermistor input. 6″ (15 cm) or 4″ (10cm) 304 SS stem and 1/4″ NPT brass adaptor with compression sleeve for adjustable insertion length. Accuracy of 0.2°C,
You will also need Solid State Relay’s - rated for switching 15-40 amps, these are the ones that are switched with a 3-8v input
The system allows for 4 inputs and drives up to 6 outputs.
For my first test , I programmed a simple RIMS mash, and did a dry run, to confirm the parameters and switching of everything. A hot water test was supposed to follow , but we ended up having people visit yesterday afternoon, so that will happen later today.
The gas control valve has also arrived , just need the pilot burner to be able to test that. I will use it with a temp probe to heat and keep to temperature the HLT water , both strike and later sparge water.
So I have started programming for the day I can get the system to start on its own, firstly a delay till on, then gas valve will fire and HLT water will start to heat and keep its temp within 2 deg for strike water.
This means I can go to bed the night before after lighting the pilot light on the gas system and wake up with Strike water ready for me.
Next will be mash in (could do this automatically with a water valve), mash stirrer ON for 5 minutes, and then into mashing for 60 minutes and RIMS will take care of hitting and maintaining the mash temp. This program is running dry at present, with two bugs which I am working on, not sure if me or the sw yet , more fun later tonight to do more tests.
Will post some pics and screen shots later.
http://zenzele-brewery.blogspot.com/
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