Happy HolidaySs Giveaway - Last Sponsor Giveaway of the Year!

Come Enter the BrewDeals/FastFerment Giveaway!


Home Brew Forums > Home Brewing Beer > Electric Brewing > Where is the best place to put the temperature sensor for a RIMS setup?
Reply
 
LinkBack Thread Tools
Old 01-27-2013, 07:03 PM   #1
Handsaw
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2012
Location: Chattanooga, TN, USA
Posts: 129
Liked 6 Times on 6 Posts
Likes Given: 10

Default Where is the best place to put the temperature sensor for a RIMS setup?

I can think of 4 places where it could be placed.
1) At the output of the RIMS tube
2) At the input to the RIMS tube
3) At the point where the wort goes back into the kettle
4) At the point where the wort comes out of the kettle.
1 and 2 have the advantage of having the control wire and power cord running more or less between the same places.
3 and 4 have the advantage of having the temperature sensor closer to the mash.
I’m leaning toward 2 right now because it has the advantages mentioned earlier plus it is not all that far removed from the mash itself. It is close to being the same as 4.
Does anyone have any opinions on this?

__________________
Handsaw is offline
mmonacel Likes This 
Reply With Quote Quick reply to this message
Old 01-27-2013, 07:13 PM   #2
P-J
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2010
Location: Charlotte, NC
Posts: 3,283
Liked 259 Times on 207 Posts
Likes Given: 454

Default

The temp probe will be controlling the RIMS element and thus the temperature of the fluid exiting the RIMS tube. I suggest that the best (and only in my humble opinion) place to monitor the temperature is in the immediate exit path of the RIMS. Placed anywhere else and there is a risk of over driving the element and thus overheating.

Also, if you experience temp losses due to wort tube length or placement, you can more easily evaluate the situation, understand it and compensate. Knowledge is power after all.

Just saying...

__________________
P-J is offline
2
People Like This 
Reply With Quote Quick reply to this message
Old 01-28-2013, 03:03 AM   #3
thargrav
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Huntsville, Alabama
Posts: 821
Liked 38 Times on 35 Posts
Likes Given: 2

Default

I agree - at the outlet of the RIMS tube. You may also want to put themometers mid way down your mash tun and at the bottom of your mash tun to see how effective you are.

You shoud see the temperature change from top down during a step mash & the speed of the change will tell you how fast your system's reaction time is.

__________________
thargrav is offline
tjpfeister Likes This 
Reply With Quote Quick reply to this message
Old 01-29-2013, 12:10 AM   #4
Handsaw
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2012
Location: Chattanooga, TN, USA
Posts: 129
Liked 6 Times on 6 Posts
Likes Given: 10

Default

At the outlet of the RIMS tube was my first thought. I reason to question that is that it will be hotter than the liquid in the pot. I hadn't thought about the pot getting hot from the top down.
Thanks for your opinions.

__________________
Handsaw is offline
 
Reply With Quote Quick reply to this message
Old 01-29-2013, 12:37 AM   #5
thargrav
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Huntsville, Alabama
Posts: 821
Liked 38 Times on 35 Posts
Likes Given: 2

Default

There is another reason to put the sensor at the outlet. If you put it anywhere else, like in the middle of the pot and the temperature drops, there is nothing preventing your RIMS from running over temp and denaturing your mash in an effort to bring the temperature up.

At least if you are regulating the output you won't go over temp. And if monitoring the RIMS outlet temp won't keep the temperature where it's supposed to be you have other problems.

For example, if you can see that your heater is cycling on & off but your mash is not being kept up to temp then you aren't flowing enough volume through your RIMS. And if your heat is on all the time & your mash is not being kept up to temp then your heater is too small.

__________________
thargrav is offline
P-J Likes This 
Reply With Quote Quick reply to this message
Old 01-29-2013, 04:11 PM   #6
Handsaw
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2012
Location: Chattanooga, TN, USA
Posts: 129
Liked 6 Times on 6 Posts
Likes Given: 10

Default

Thanks,
I have moved the temperature probe to the output of the RIMS tube.
I'm doing BIAB with 120V and have to do the boil with propane so there is no insulation and thus a tremendous amount of heat loss during the mash. I thought about the potential of denaturing the mash at one point, but that dropped out of my consciousness during the build process.
I plan to bring the water up from room temp to strike temp with the RIMS tube and during that time I would like for the element to be at 100%, but I also want the PID to regulate once it gets there. That is what put the idea in my head of putting the probe at the input of the RIMS tube instead of the output. The idea was that I could set it up and leave it on its own and not have to watch and wait while it heats, but I guess if I’m not going to be there watching, then it doesn’t matter if it takes longer to get up to temp, does it?

__________________
Handsaw is offline
 
Reply With Quote Quick reply to this message
Old 01-29-2013, 04:20 PM   #7
naamanf
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Manhattan KS
Posts: 43
Liked 2 Times on 2 Posts

Default

Why don't you propane heat the strike water and then put a removable insulation sleeve on it during the mash?

__________________
naamanf is offline
 
Reply With Quote Quick reply to this message
Old 01-29-2013, 05:12 PM   #8
PeteNMA
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2012
Location: Ellicott City, Maryland
Posts: 200
Liked 12 Times on 12 Posts
Likes Given: 3

Default

PID works best where the control point is closely linked to the input point so that it gets very rapid feedback of the results of changing the input. Ie as it increases heating power it sees the increase in wort temperature.

The further away you put the probe from the heater, the greater the response lag and the worse the stability will be. If the controller increases power and doesn't see a temperature increase, it will keep increasing power until it does. Either it ramps the power to 100% and burns your wort, or it ramps very slowly and you get bad temperature control.

__________________
PeteNMA is offline
P-J Likes This 
Reply With Quote Quick reply to this message
Old 01-29-2013, 11:58 PM   #9
thargrav
Registered User
Feedback Score: 0 reviews
Recipes 
 
Join Date: Dec 2009
Location: Huntsville, Alabama
Posts: 821
Liked 38 Times on 35 Posts
Likes Given: 2

Default

The problem with putting the measurement at the input is the temperature will over-run, particularly when bringing your mash up to temperature. And even after you are at temperature your mash temp will cycle because the warmer mash fills from top down.

__________________
thargrav is offline
 
Reply With Quote Quick reply to this message
Old 01-30-2013, 01:33 AM   #10
Handsaw
HBT_SUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Mar 2012
Location: Chattanooga, TN, USA
Posts: 129
Liked 6 Times on 6 Posts
Likes Given: 10

Default

Well, I tried it out this afternoon. I put the sensor at the output of the RIMS tube and let the pump run full bore. I heated 9 gal of water and had the SV at 160F. The water coming into the kettle (about 18" or less of hose after the RIMS tube) was barely warmer than what was in the kettle. This is a good thing because the PV on the 2352 was usually only about 2 degrees higher than the temperature showing on the Brewmomenter in the kettle. When it got to where the PID was controlling the PV and the Brewmomenter were right together.
The problem I have, and I've seen it mentioned in another thread, is that the PV settled in at 163 - 164 instead of the SV of 160.
Do any of you know what to do about that (other than setting the SV 3 degrees low)? Have you seen a thread mentioning this problem?
Thanks

__________________
Handsaw is offline
 
Reply With Quote Quick reply to this message
Reply



Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Mash water temperature sensor with alarm slackerlack Equipment/Sanitation 7 01-03-2013 10:07 PM
PID and I2C Temperature Sensor? TriangleIL Electric Brewing 17 02-22-2011 09:49 PM
temperature sensor to 10 bit ADC cheese Electric Brewing 10 12-14-2010 07:55 PM
Temperature sensor for DAQ board cheese Brew Stands 4 10-28-2010 07:09 AM
K Type Thermocouple vs RTD temperature sensor maxbing Brew Stands 13 08-03-2010 01:04 AM



Newest Threads

LATEST SPONSOR DEALS