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Jonnio · 09-15-2008, 10:54 PM

Quote:

Originally Posted by Bopper359

Just a side note from a legal perspective...have you been considering patents for the design? You can get patents for the current design and get new ones for subsequent modifications to the base prototype. If you are considering selling this thing (which you definitely should) I'd consider getting them sooner rather than later (if you haven't already), especially since you are sharing information on a public forum. Would hate to see someone profit from your ideas, albeit you haven't shared significant detail.

Again, congrats on this project! It's amazing.

I am not a patent attorney, but I think the US is first to invent, not first to patent. Basically if he does have something that is unique enough to actually patent (so far it appears to just be a kick ass HERMS setup with copyrightable software) then posting on the forum might be the best way to prove first invention.

LabJackSupport · 09-15-2008, 10:55 PM

Quote:

Originally Posted by kladue

Have you taken a look at the LAB-Tick amplifier board for the Ph probe?, looks like the input impedance would work, just need to bias the Ph probe with +2.5 V to get full range output. As to probe maintenace and signal loss from electrolyte dilution you can prolong the life of the probe by storing the glass element in the concentrated electrolyte solution when not in use.

We sell a couple instrumentation amplifiers (EI-1040 and LJTick-InAmp), but they both have 10s of nA of bias current which might be too much for pH probes. 10 nA is low, but a pH probe needs really low bias currents. If the probe has 100 Mohm of resistance, then 10 nA trying to go through it will cause a 1 volt offset. Perhaps that offset would be consistent enough that you can calibrate it out, but I am not sure.

I would get something specifically made for pH. Have not tried the following, but it looks reasonable:

Electrode Amplifier

**John Beere** · 09-15-2008, 10:56 PM

After talking with their support staff, they didn't seem to think it had enough amplification. I'm at you EE's mercy on this one... I haven't talked price with Full Throttle yet, but I think he might have a good solution.

I have put off the PH module just trying to get everything else wrapped up... still working on the algorithm which holds the mash temp. My goal with it is to maintain +- .25 differential of any set point.

**John Beere** · 09-15-2008, 10:58 PM

Quote:

Originally Posted by LabJackSupport

We sell a couple instrumentation amplifiers (EI-1040 and LJTick-InAmp), but they both have 10s of nA of bias current which might be too much for pH probes. 10 nA is low, but a pH probe needs really low bias currents. If the probe has 100 Mohm of resistance, then 10 nA trying to go through it will cause a 1 volt offset. Perhaps that offset would be consistent enough that you can calibrate it out, but I am not sure.

I would get something specifically made for pH. Have not tried the following, but it looks reasonable:

Electrode Amplifier

Welcome aboard! I'll have you guys homebrewing before you know it... heh

**kladue** · 09-15-2008, 11:04 PM

The electrode amplifier looks like the right device for the job with out a lot of tinkering. Have you implemented a PID program in your code for HEX control?, found one written in C+ but have not had a chance to run it yet.

**John Beere** · 09-15-2008, 11:19 PM

Quote:

Originally Posted by kladue

Have you implemented a PID program in your code for HEX control?, found one written in C+ but have not had a chance to run it yet.

For better or worse, I started this app without any preconceptions of how existing PIDs worked... so I'm sure the mechanics of how mine works doesn't follow anything else. The master config for the app allows you to set the differentials for your rig and the application controls the heat based on these settings. It has a mash differential and a HEX differential. The HEX differential is what I've refer to as "Scorch Guard" as it keeps the HEX from going over the current mash temp + hex differential.

bakins · 09-18-2008, 01:52 AM

Quote:

Originally Posted by Bopper359

Just a side note from a legal perspective...have you been considering patents for the design?

Not sure he can patent anything. He can copyright the software. This is very similar to several systems that have been posted on here before (a few steam ones). He has polished it up very nicely, but lots of examples of "prior art." Also, in a lot of ways it's very similar to a brewmagic, as well. Now if a complete system costs alot less than a brew magic, I'm sure he'd have plenty of customers.

I started mocking up some software today. Looks like crap compared to John's, but could easily replace my 2 PID's for my current electric brew cart. Hardest part is writing a gui - I'm a systems guy - the other stuff is pretty straight forward on an Arduino. The labjack stuff is just too "closed" for me.

Good luck John! Keeping the price down, IMO, is key to your success.

**kladue** · 09-18-2008, 03:21 AM

I am sure by now that John has discovered that the hardware assembly and wiring was the easy part, building the code and GUI's is the long and tedious part of the system development.

illnastyimpreza · 09-18-2008, 03:28 AM

absolutely RIDICULOUS

Kauai_Kahuna · 09-18-2008, 06:53 AM

OK, count me in as a very interested person, but I may have to wait till I can buy a house to fit this beast into. Hey maybe by version 3.1