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How many temp probes are ideal?
kwrcst
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Posted on 01/26/2020 9:21 PM
So I?m almost done with Frankenstein and I?m ready to put in the probes. The drum spins clockwise so I have the BT probe at about the 7:30/8 position and I have an ET probe in the hopper at the bottom where it meets the drum. It is where a lot of drums have a manual thermometer. Do I need another inside the drum in the back? One outside the drum to measure heat entering? Should I use the one in the hopper as my exhaust temp? It is below the exhaust port but in line with the air flow as it exits the drum. Thoughts?
 
renatoa
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Posted on 01/27/2020 2:06 AM
For me real ET is the most important.
Is the hot air that make the most of roast, contact and radiation are just marginal.
Exhaust air tells nothing to me.
So I would try to push the ET thermometer as deep as I can into the drum, to be sure it measures same air that are beans immersed.
 
kwrcst
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Posted on 01/27/2020 7:45 AM
So would you consider the probe just outside the drum at the hopper's mouth to be an Exhaust probe?
 
renatoa
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Posted on 01/27/2020 9:33 AM
Almost at limit... hopper's mouth is actually front plate, right? so part of the oven, along with the drum I think...
Extending the tip of the sheath inside, to place the junction almost touching the drum spokes, would be enough to qualify as ET probe. Assuming there are no beans flying in that area...
 
kwrcst
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Posted on 01/27/2020 11:02 AM
Yes. It?s on the front plate and as close to being in the drum as I can get. I guess I?ll have to finish it off and see how the temps read
 
renatoa
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Posted on 01/27/2020 12:49 PM
Check how close are BT and ET when preheating empty.
 
BobbyS
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Posted on 02/15/2020 6:06 PM
My probes are on the front plate and I have two. The ET is close to the center of the drum out of the bean path. The BT is in the door and will read lower than ET until hot.

I have found on mine the BT and ET won't be close until the roaster pre-heats enough. That is when I know it is ready to roast. Just remember, all machines are different in what they do. You will need to "get to know your roaster".

They have a mind of their own so keep an eye on em' lol.
 
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