Programming Help(Control one output with two different probe

[WhiskeyFingers]

Can anyone give some programming insight? I am a new user and now have two brew days under my belt with the BCS. Here is my problem.

During my preheat stage I am controlling the temp setpoint of my HLT and MLT (by turning my burners on) with a temp probe on the output of a corresponding pump because i am circulating while firing. During my mash stage i would like to control the HLT burner on and off but this burner is already associated with a particular temperature probe. I have to switch the probe to a different location while brewing which causes hot liquids to get spilled and seems silly. i have four probes installed but am only using two because it seems that i cannot associated my burners with more than one input.

Let me know if that made any sense. i can rephrase it as needed.

Thanks

[ECC]

Hey Whisky. Yeah I agree, you shouldn't have to physically switch probes.

In firmware 1.3 and earlier, temp probe associations (as well as pid/output settings) are considered static for each output, and not allowed to be changed on the fly. In v2.0, we introduce the "Alternate PID" feature, which allows you to switch temp associations on the fly, but I'm not sure that we need it in this case. This feature isn't documented fully yet, but will be when I release v2.0 at the end of this week.

Just so I fully understand, you have a 2 pump system? When preheating, you have one pump circulating the MLT, and one pump circulating the HLT. Direct fire, or HERMS? Or probably HERMS with direct fire assist?

[WhiskeyFingers]

I do have a two pump system that I have been using as a HERMS. I can direct fire all three kettles if needbe(direct fire assist). So currently I need to stick with my method of moving my sensors?

Here is a pic of my system nearly completed.

[ECC]

Wow. That is one beautiful machine. As soon as I saw it I had to scour the web for a build thread (http://www.homebrewtalk.com/f51/iron-du ... day-146061 if anyone's interested)

So if you want to use it as a herms, you want to control the MLT temp by applying heat to the HLT, is that correct?
Preheat State:
MLT Flame Output => Heat to XXX temp associated with MLT Probe
HLT Flame Output => Heat to XXX temp associated with HLT Probe
Both Pumps ON
Mash State
MLT Flame Output => Off
HLT Flame Output => Heat to XXX temp associated with MLT Probe
MLT Pump On for HERMS recirc, HLT pump on to recirc for even heating?

With your system, you really have the flexibility to do a strictly Direct Fire (ala Brutus) or a HERMs. Thats really cool, you can play with both if so inclined . You could even have a different BCS process for each, run one process in HERMs mode and one in Direct Fire mode depending on the brew.

So, to answer your question, if you want to change the temp probe association your going to have to get the v2.0 firmware update. It WILL be done later this week. As I alluded to before, the feature that you can use is 'Alternate PID'. This allows you to take the normally static Output parameters from the System Setting page, and swap them on a state-by-state basis. So in the System Settings page, your normal output settings probably look something like this. 6 outputs, 6 sets of parameters contained in the tables.

System Settings_altpid.jpg (94.33 KiB) Viewed 5775 times

To swap the temp probe association in your Mash State, enable the alternate pid of the HLT Flame Output to use the settings from the MLT Flame Output by checking the enable and choosing the correct output in the pulldown.

altpid_state.jpg (59.91 KiB) Viewed 5775 times

Not only will you get the temp probe association, but you will get PID settings and everything in the table as well, so you have to be a little careful if you have uniquely tuned PIDs. These settings only apply to this state, so they will revert back to 'normal' temp probe association when you leave this state.

Hope this helps.

[WhiskeyFingers]

Wow, Thanks for the extremely thorough response. It looks like my timing on this question is right on the money since you plan to release an update very soon.

As far as the operation of my system goes, you are spot on. I have it programmed as you stated. Will this firmware upgrade be difficult to do. I am a new user and still learning to use the controller up to its potential.

[ECC]

The firmware update is really easy, documented here: http://www.embeddedcontrolconcepts.com/ ... g_Firmware

At least I think its easy because I update my controller at least 4 times a day testing out new code .

[ECC]

Documentation for the Alternate PID feature has been updated:
http://www.embeddedcontrolconcepts.com/ ... ernate_PID

Not much new here, since I basically used your question as an example.