Artisan Spike Help with ROR

[alejandrooo]

Thanks everyone for their help thus far.  First few roasts went well other than the ROR/change in BT readings, which even after reading about other people with Artisan spike problems here or other forums, doesn't seem to have an easy solution.

I'm using a Variac (for exhaust fan) that's plugged directly into an outlet or a power strip (tried both).  My other cooling fan, and motor power cord is plugged in.  Using a MacBook Air that's not connected to an outlet (just battery), and I have a Phidget, which seems to be set-up properly with its other readings (BT, ET, MET), and its settings are those very helpfully outlined by Susan's guide: https://drive.google.com/open?id=0B4HTX5wS3NB2SmZua2VSd2FjZFE.  I made sure red wire is left in numbered slot and black to G.

Here are some photos of my set-up and first few roast graphs:

https://goo.gl/photos/Z3rDKTrYCym7dRfa8

As well as an Artisan graph when I had no beans and was just trying to isolate the issue (e.g. plugging Variac directly into wall 3 proned socket, upgrading my Artisan version to Artisan 0.9.9, etc.). 

https://goo.gl/photos/VcfeHSemvdPDwMXC9

Anything stand out I might be doing wrong or that could fix this?  Really hoping it's something boneheaded I did and easy to remedy, but open to testing whatever and get into the weeds to resolve it.

Final note: I don't think it's grounding because I'm not letting it touch anything metal that would then connect to ground (I'm set-up on plastic table).  The wires are intercrossed a bit if that's a problem though as you'll see in photos. 

[SusanJoM]

I don't think it looks like a grounding issue either.  It looks like maybe you are taking samplings too closely or not applying a reasonable amount of smoothing??

What does your Tools > Extras page look like?
And what is your Sampling Interval.

[alejandrooo]

Thank you for the help, Susan.  Here are my settings:

https://goo.gl/photos/wVcMriGaPkUEKo9CA

https://goo.gl/photos/JcvNBZiGyYQG6td16

[SusanJoM]

Well, try changing your Smooth Curves from 0  > 1 and seeing what the curves look like then. You can use the data that you already have (as in open the current profile), make changes, and see what it does on the screen.  My settings on that page are Smooth Curves = 1; Smooth Deltas = 2.  Just play with those settings a bit and see if it gets easier to read.

And maybe read this
https://artisan-roasterscope.blogspot.de/2014/01/sampling-interval-smoothing-and-rate-of.html

[alejandrooo]

Thanks, Susan, I'll give that a shot. 

Do you guys have any other ideas that might help identify potential issue?

And maybe most importantly, how can I best troubleshoot...should I turn on heat and motor and from there test what happens when I turn on fan or move kPa, etc.?  Yesterday, in my third roast, I tried creating a stable environment with no beans, motor on and very low kPa and airflow, but that still saw the ROR jumping around quite a bit (more than a normal variance of 5-degrees plus or minus), which is why I'm convinced it's something electrical or beyond my technical knowledge.

[alejandrooo]

Quick update: even as I watch my BT stay more or less flat over 5-10s intervals, by change in BT reads completely irrelevant numbers (E.g. BT stays at 350 for 5s and then becomes 351 after 10s, but the change in BT is 5 or -4 or something screwy). 

Does that give anyone a clue as to what might be causing this?  Could it be Phidget itself, something to do with how I have the wires all together with a tie, electrical interference, or other? 

[alejandrooo]

Update from Phidget Support: "The Phidget 1048 merely records the voltage from the thermocouple, and then converts to degrees Celsius or Fahrenheit. If there's a disagreement between your temperature measurement and the delta-temperature, then it would be an issue with the program (in this case, the Artisan software) since all of these calculations are done after the Phidget reports the value from the thermocouple. If the base temperature readings are normal, then the Phidget is behaving normally."

Given all the forums I've read where people had similar issues as myself, with change in BT spiking, but regular BT readings okay, I still believe there could be an interference issue from other cords, needing to ground the Huky.  I've bought a new USB cable to try that too and some of the Ferrite clips (https://www.amazon.com/gp/product/B009ENG6TI/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1) to put on the TC wires.  Also thought about getting the USB Isolator 3060 (http://www.phidgets.com/products.php?product_id=3060) as a last resort.

Does anyone think using a power strip has to do with this, which I plug the DC motor, the cooling fan, and the Variac.  The power strip is then plugged into a grounded outlet. 

Appreciate all the help I can get!  Thanks

[SusanJoM]

Does anyone think using a power strip has to do with this, which I plug the DC motor, the cooling fan, and the Variac.  The power strip is then plugged into a grounded outlet. 

These ideas should be very easy to test.
Unplug  'em.  See what your profile looks like.

[SusanJoM]

And, if that doesn't get you sorted, I suggest you ask  your question at the Artisan User List.  There are lots more people using Artisan there.  The information is in the Resources section. 

[alejandrooo]

Good idea, thank you

[balzajko]

hey got similar problem at the moment with spikes in deltaBT  , tried to reconnect all the phidget cables again and it somehow got better but still a little noisy,
I think its a grounding issue. Let me know if it worked for you as i am still trying to find a solution, when i get home will post a graph.

[alejandrooo]

Do you mean you just unplugged the thermocouple wires in and out of the Phidget and that helped? 

I'm still not sure how much of this is me being new and how much is true noise.  I've insulated my thermocouple cables with aluminum foil, which helped.  I tried grounding and checking my outlet was okay, and both weren't the issue.  I also feel setting up smoothing on Artisan per here which has helped.

All other ideas welcome.  I get this same weird drop and then speak right after the turn.

https://goo.gl/photos/pFNGKkFk6cTq7qVJA

[SusanJoM]

I'm still not sure how much of this is me being new and how much is true noise. 
https://goo.gl/photos/pFNGKkFk6cTq7qVJA

I don't see any 'noise' in that profile at all.
Looks to me like a normal response to changes in heat and air, the settings for which your profile doesn't show.

[alejandrooo]

the smoothing really helps that.  I'm finding that if I"m not constantly working the airflow and gas gauge, it'll look like this and really get away from me.  There's no wind at all where I"m roasting either, so that's where I still feel I've got some noise issues. 

[alejandrooo]

This last roast I did got a bit better, but I still need to focus on flattening out my ROR curve.  I'm at the front end of the roast having issues where my initial drop isn't as step, nor is rebound, and I'm wondering if I increase airflow if that would help a bit or if people think I shouldn't worry about that?

My TP is pretty high as well here vs. what Scott Rao shows in his book of 170-200F. 

What I'm starting to figure out is that if I start the roast with no to little heat, then slowly increase in first 2 minutes to my max, then use airflow to bring it control the spikes until DE and a minute or so before FC, I can then start to bring down the temperature little by little until the end, using more air if needed as well to control the spikes.

It's a lot of manual adjustments for my machine and set-up, possibly because of the noise I'm having, but starting to get it and open to any thoughts people might have on how I can further improve