Pumps.. In general people like
March Pumps, but
Chugger is their cheaper competitor.
For automation on heating, you can either go electric elements or use a controlled regulator on propane/natural gas. My understanding is electric might have lower equipment costs, but heating efficiency of gas is higher and it's still cheaper (this will change as solar efficiency increases and gas becomes scarce).
Temperature probes will be dependent on automation platform you choose. Normally this will be either RTD's or DS18B20's. Here I think the tradeoff is more accuracy vs temperature sampling rate. I would assume the RTD's need calibration more frequently and would drift compared to the DS's, but the DS's have to be polled for data which means there is a limit to sampling rate... but it's still under a second so whatever...
As for automation, it all depends on many things...
How much do you want to do from scratch?
How comfortable are you with assorted programing languages?
How adaptable do you want the system to be?
ect...
The main (as I understand it) automation systems that homebrewers tend to start out with are either
BCS (Brewery Control System) or
Brewtroller. Differences here are BCS = closed source hardware/firmware, though they have an open API. Brewtroller = open source everything, hardware is based on Sanguino which is a somewhat beefier Arduino derivitive. BCS is the more user friendly of the 2 with its web based interface, but Brewtroller is more customizable though requiring some level of being able to read code written in C.
The step beyond that is to go the route of prototyping your own controller with Arduino/RasberyPi/Beaglebone... or any number of other micro-controller architectures. This gets deeper into needing to be able to read/write your own code with the language being dependent on the platform. There are several project on the forum here which are doing this so you can use them as a base and work from there. This provides great expandability and customization, but won't be up to industrial standards.
The last step would be going the PLC route that trillium is talking about. Industry quality controls provides very good level of expandability and customization. This though comes at a price as the software and hardware are all proprietary but well supported and documented so you get what you pay for.
I'm a seniora at Purdue University in the College of Technology.
And I'm happy to see more ladies in homebrewing
