The following is what I would like to do, and my question is what Hardware do I need to make this work.
I have a new Spike Flex fermenter. It has a SS coil immersed in the wort for cooling, a heating pad for heating, and a 1/2" NPT Thermowell. I also have a Tilt Hydrometer. I would like the BrewPi to control the temp for the fermenter, and log the Tilt data. Is it possible to have the BrewPi react to changes in SG as read by the Tilt? What do I need to run all this? I would need the BrewPi Spark. Is just one of them sufficient to run BrewBlox on and control the fermenter? I would also need the one wire NPT temp sensor. What relay do I need? Is one sufficient to run both the pump for coiling and the heating pad? Just wondering what I need to purchase to make this all work?
You definitely need separate relays for the pump and the heating pad. What types of relays you need depends on the power requirements of each (critically whether they use AC or DC).
It might be nice to have a couple extra one-wire temp sensors to log room temperature and the temperature of whatever fluid you are pumping through the coil (also if you already have a thermowell, do you want the NPT version or can you just stick the basic version in the existing thermowell?). Further, you might consider a third relay to control whatever is chilling this fluid (unless you already have a solution for that which you are happy with).
Someone is working on a brewblox module to integrate tilt readings (you can follow their progress on the thread in this forum). Theoretically, it should eventually be possible to use the (probably rate of change of) SG as the input for the Beer PID, but I don’t think anyone has experimented with this yet.
One spark is sufficient to control the fermenter. Brewblox runs on a separate device–the cheapest and most convenient option is a raspberry pi 3, but you could theoretically use just about any computer you have lying around that is connected to your local network.
Thank you. This does help. One of the big things I was unsure of was the need for a secondary computer/raspberry pi to run brewblox on.
One followup question. The thermowell is a 1.5 inch TC that has a 1/2" NPT on it. The one wire on the site for sale is 1/2" NPT. I thought that this would be an easy attachment. Is it better to just use a regular temp sensor shoved into the thermowell? Or is it just less expensive?
I don’t know if there is a right or wrong answer. I would just shove a regular temp sensor into the thermowell. Assuming this is what you are talking about, the advantage of using a wire sensor is you can get it much further down into the thermowell, eliminating some airspace that would act as an insulator (not that it would make that much of a difference). Conversely, if you screw something in, it’s not likely to accidentally get pulled out.
If you want to pack the well with thermal grease (as they suggest) then the threaded sensor is probably best to keep things from getting messy.