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snwcmpr
03/20/2019 4:17 AM
Eth Yirg Nat Idido Gr1 today.

snwcmpr
03/18/2019 8:15 AM
1 lb roasted lasts a week. I can taste the flavor increase to peak, then drop after. Still very good, but interesting to follow the wave of flavor rise and fall.

snwcmpr
03/11/2019 4:10 PM
Roasted Panama Gesha Esmeralda yesterday. Yummy.

Beebee74
03/11/2019 3:10 PM
I seem to have lost any roasting touch I thought I had. Very frustrated to be wasting time and money. I’m hoping someone can provide some insight on roasting at high altitude. I’m at 4400ft. Thank

aicardo
03/07/2019 8:50 AM
tb

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TC4+ Arduino coffee roaster shield (TC4-compatible)
Ilovehash
Is TC4+ compatible with MEGA 2560? Is the flyback diode necessary? If so, for 20V 2A DC motor, what would be the appropriate diode to use? I believe 400x only get up to 1A which might not be sufficient.
 
mg512
I think the Mega won't work, since the I2C pins are different. The aArtisan code also uses some specific timer registers of the Atmega328P that's on the Uno, I wouldn't be sure those are the same on the 2560. Is there any specific reason you want to use the Mega?

The flyback diode is necessary, yes. Or at least, there's a high risk of damaging the MOSFET without it. There is higher current versions of the 400x diodes, see e.g. the table on the wikipedia page: https://en.wikipedia.org/wiki/1N400x_general-purpose_diodes
 
https://www.tindie.com/products/15798/
mg512
Oh, to add to that: If you are building a roaster out of a popcorn machine, the DC motor almost certainly was attached to a bridge rectifier made up of four diodes. The easiest thing to do is to simply reuse one of those - they ought to be the right specification for the motor, obviously.
 
https://www.tindie.com/products/15798/
Ilovehash
Reusing diode on the popcorn machine fan rectifier is a wonderful idea. Do you have capacitor across the motor on TC4+? I heard some people have problem with Arduino being reset due to DC motor power issues. What about noise from PWM? Do we need to filter it? As to MEGA2560 question, I thought it has more memory to handle aArtisan sketch. My impression is some configuration might run out of memory on an UNO.
 
renatoa
You can save significant amounts of memory commenting out the unused thermocouple types in the TC code.
For example if your TC type is K, then the code dealing with J and T types is simply occupying memory without never being used. And is a lot if bytes... hundreds.
Already did this, PM me for the files if you want to test.
 
mg512
Ilovehash wrote:

Reusing diode on the popcorn machine fan rectifier is a wonderful idea. Do you have capacitor across the motor on TC4+? I heard some people have problem with Arduino being reset due to DC motor power issues. What about noise from PWM? Do we need to filter it?


The motor in my popcorn machine had a few (small) capacitors across the positive and negative terminals, positive and motor housing, and negative and motor housing. I left those in place, but I didn't add any extra ones.

The only times I've had issues is when switching the motor on from 0 to 100% duty cycle, and even then only on a 24V power supply (when the motor is nominally about 20V). That plainly triggers an overcurrent protection in the power supply, and hence everything including the Arduino resets. I tried adding an extra capacitor but that didn't help. I'm sure a correctly specified capacitor would do the trick, but I've just never been bothered - I don't even usually use the fan at 100% anyway, and going 0->80% isn't an issue. Also never happened on the 19.5V laptop power brick I was using previously. I have also never had any issues with PWM noise, despite always running the fan at a partial duty cycle. Between the capacitors that came with the motor, and those on the voltage regulator on the TC4+, that seems to filter out plenty.

So, I would leave any capacitors that are already there in place. And I wouldn't worry about it beyond that, unless you actually run into problems. Even then, just gradually increasing fan speed would almost certainly be enough.



Ilovehash wrote:
As to MEGA2560 question, I thought it has more memory to handle aArtisan sketch. My impression is some configuration might run out of memory on an UNO.


Ah, okay. I wouldn't worry too much about that, again unless you run into a specific issue with it. I think it would really only happen if you wanted to enable _all_ the aArtisan features at the same time, like both PWM and phase-angle control simultaneously, but that would not even make sense except in the most exotic of configurations. Even then, as renatoa points out, there's plenty of unused code that you could comment out if needed.
 
https://www.tindie.com/products/15798/
AlexMunt
Hello to all, and thanks to you for sharing all this information. Awosome!!
I have some questions about the shield and its configurations. I don't know if I can post here , sorry if I'm wrong.
I bought a TC4+ a few weeks ago. Works fine on a Arduino Uno and aArtisanQ_PID loaded on it, with CONFIG_PAC2; Artisan 1.5.0 instaled, configured, and works well too. ( at this time only with Heater and temp. sensors)
My idea is to build an electric drum roaster, so I need to control a heater (230VAC resistor), a fan (230VAC, motor 32W), and the drum speed (12VDC gear box motor 40rpm).
On OT1 I have the Heater and works fine, with SSR.
On OT2 I have nothing yet but will be the Fan, with the ZCD on IO2.
On IO3, PWM 3,9KHz, to control a 12VDC motor. On this one I don't know how to configure the third comand from Artisan? Could you tell me if I can do it? And how.

The ET and the BT works fine.
Didn't test the bluetooth yet, but I will.

Very excited so far by the TC4, and thanks a lot!!
 
greencardigan
Just use the IO3;X command to change the PWM output on the IO3 output. Essentially the same as the set up for OT1 and OT2.

For example, set up a slider with the serial Command IO3;{}

Or buttons with serial command IO3;100 etc.
 
mg512
Also make sure you're using the latest version of the aArtisanQ_PID sketch. IIRC in earlier versions you couldn't do PWM on IO3 if you were using PAC config.

And let us know how it goes! :)
 
https://www.tindie.com/products/15798/
AlexMunt
Thank you both for the fast answer.
I have downloaded aArtisanQ_PID_6_7.zip from Greencardigan's github page, 4 months old docuemnt. I think is the latest version.

I will test the button and the slider with IO3, and let you know the results.
Thanks again,
 
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