Author Topic: An easy to build android/bluetooth reflow controller  (Read 29476 times)

bazc

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Re: An easy to build android/bluetooth reflow controller
« Reply #15 on: February 26, 2016, 02:24:04 pm »
Great work Andy, now works a treat with my tablet !

FYI - I did try with a an android phone before the update firmware and it did work, I suspect it loaded the updated app so cant tell you if it would have worked with the earlier version.

I now have a fully working oven which I can thoroughly recommend to anyone.

what would be nice if you can do it, a spare output on ATMega8L to go high when cooling stage starts. I want to try drive a cooling fan.

Barry

Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #16 on: February 27, 2016, 01:37:57 am »
Quote
Great work Andy, now works a treat with my tablet !

Great news Barry and thanks a lot for working with me to get this sorted out.

Quote
what would be nice if you can do it, a spare output on ATMega8L to go high when cooling stage starts. I want to try drive a cooling fan.

Interesting... due to flash space issues it would have to be a single GPIO that goes high during the final reflow stage (the cool down). Pins 6 and 26 are currently available for use.

Looking to the future,  I think I'll be doing a 'version 2' board at some point that will include an extra transformer footprint for US users on a 120VAC supply. I'll also upgrade the MCU to the venerable 328p seen in the Arduino Uno which will give me more flash space to include a PWM fan output that would be driven at a duty cycle matching the degree of cooling required. That won't be until much later this year though.
It's worse than that, it's physics Jim!

Glen

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Re: An easy to build android/bluetooth reflow controller
« Reply #17 on: March 25, 2016, 09:51:26 am »
Hi Andy,

Loving the site, well done :)

I'm going to have a go at the bluetooth reflow oven, however on uploading the gerber files to dirtypcb, I get the following error

No board outline (GML/GBR/GKO) file: you should include the board outline on a layer with one of these file extensions. This is done through the CAM processor of your CAD program.

I've already paid for the order, and I don't have access to any software that would allow me to add a board outline. Can you add a board outline to the zip?

Cheers

Glen.

Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #18 on: March 25, 2016, 11:35:21 am »
Hi Glen,

The board outline is actually included on all layers but it looks like their software specifically requires it to be included separately on a mechanical layer. I've attached it on the GML layer. If you want to verify that it's correct then simply load it up into a Gerber viewer along with the other layers and they should all be aligned correctly.
It's worse than that, it's physics Jim!

Glen

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Re: An easy to build android/bluetooth reflow controller
« Reply #19 on: March 26, 2016, 10:05:25 am »
Hi Andy,

Thanks for that. Once I included that file, the site accepted the gerber files without any problems.

Cheers

Glen.

JohnBurton

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Re: An easy to build android/bluetooth reflow controller
« Reply #20 on: April 10, 2016, 10:29:34 am »
Hello,
I'm building myself a similar project and I'm in the testing phase.
I am reading a thermocouple on my microcontroller and it seems to work once I figured out the SPI settings.
The temperatures look plausible.

However I find that the thermocouple takes a very long time to cool down.
Even if I remove it from the oven it seems to only cool at the rate of one degree every few seconds, taking maybe 3 minutes to cool from 150 degrees to 50.
Does this seem normal?

JohnBurton

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Re: An easy to build android/bluetooth reflow controller
« Reply #21 on: April 13, 2016, 03:13:11 am »
I found what the problem was, I had connected up the thermocouple chip to my microcontroller wrongly. Frankly I don't understand how it was working at all.

I'm finding that I have to turn the oven on and off fairly frequently to maintain accurate temperature control. For example making a decision to turn it on or off every second.  I worry that the fan and heater are going to be damaged by doing this several hundred times over the space of making a single PCB.
Has this been a problem?


Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #22 on: April 13, 2016, 01:35:02 pm »
I found what the problem was, I had connected up the thermocouple chip to my microcontroller wrongly. Frankly I don't understand how it was working at all.

I'm finding that I have to turn the oven on and off fairly frequently to maintain accurate temperature control. For example making a decision to turn it on or off every second.  I worry that the fan and heater are going to be damaged by doing this several hundred times over the space of making a single PCB.
Has this been a problem?

Hi John, my controller can adjust the duty cycle to a new percentage at an interval of 300ms. Are you pulsing on/off instead of dimming with a triac? You get much better control with dimming and the higher update frequency helps keep it on track with small nudges in the right direction.

It's worse than that, it's physics Jim!

JohnBurton

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Re: An easy to build android/bluetooth reflow controller
« Reply #23 on: April 14, 2016, 01:32:24 am »
Well, I already had a solid state relay so I've used an incredibly cheap stm32f prototype board and a themocouple input module and a bluetooth module to hack together a controller and a breadboard. It's amazing what you can do with about 4 parts :P
I guess it's inspired by your first reflow project although I'm using a bluetooth module to control it like your second because it's such a easy way to interface to a project now :)

I'm doing some very basic PID control to work out the 'strength' of the heat needed at any given time and then each 6 seconds turning on the heater for 1-6 seconds depending on the strength required. The temperature fluctuates a bit but seems to remain within a few degrees of my target overall.

I've made a few simple SMD boards with just some 0805 leds and resistors on as a test and they seem to have worked perfectly :P

I don't like turning the heater on and off so often though, apart from the fact that it makes exact control impossible I'm sure it won't do the heater any good.

I guess my plan is to get the current breadboarded version working well enough that I can use it to build a more advanced second version. I'm lacking confidence in using mains power directly safely but I expect like anything else, I can carefully learn.

Thank you for your projects, as well as being useful to me directly, they have inspired me to do a lot more with my hobby than I might otherwise have done :)

Glen

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Re: An easy to build android/bluetooth reflow controller
« Reply #24 on: September 09, 2016, 12:55:07 pm »
It would seem as though the BTA312-600B is now discontinued, would the BTB616-600SWRG work as an equivelent?

If not, any suggestions?

Cheers

Glen.

Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #25 on: September 11, 2016, 12:52:49 am »
It would seem as though the BTA312-600B is now discontinued, would the BTB616-600SWRG work as an equivelent?

If not, any suggestions?

Hi Glen, try the BTA12-600BWRG by ST Micro. It appears to be a direct replacement with the same 3Q triggering and current characteristics.

Google couldn't find the part number you quoted but I can guess from the code that it's a non-insulated (the tab is live) version with a more sensitive gate current (10mA). I prefer to use the insulated versions and while the 10mA gate variety will probably work I haven't tested it so couldn't say for sure.
It's worse than that, it's physics Jim!

thailoz

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Re: An easy to build android/bluetooth reflow controller
« Reply #26 on: January 29, 2017, 01:55:45 am »
Hi thanks for an interesting project

I downloaded the pcb files and see that they are all surface mount components do you have the original Th design as at present i have no way of re-flowing smd and don't relish the thought of hand soldering them (read eyes not too good )

thanks

Laurence
 

Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #27 on: January 29, 2017, 05:00:05 am »
Hi thanks for an interesting project

I downloaded the pcb files and see that they are all surface mount components do you have the original Th design as at present i have no way of re-flowing smd and don't relish the thought of hand soldering them (read eyes not too good )

thanks

Laurence

Hi Laurence, I think that you may have downloaded the gerbers for my earlier project. Here's a direct link to the gerbers for the android/bluetooth project.
It's worse than that, it's physics Jim!

DeNew Lab

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Re: An easy to build android/bluetooth reflow controller
« Reply #28 on: March 28, 2017, 03:38:11 pm »
Thank you very much for the project Andy!

I have quartz heaters of 6 pieces 500 Watt = 3000 Watt
Instead of a triac and an optocoupler, you can connect a solid state relay (SSR-25DA maybe)



https://www.aliexpress.com/item/1-pc-SSR-25DA-Solid-State-Relay-Moudle-SSR-25-DA-25A-Hot-Sale-Quality-1/32767243749.html
« Last Edit: March 28, 2017, 03:40:30 pm by DeNew Lab »

Andy Brown

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Re: An easy to build android/bluetooth reflow controller
« Reply #29 on: March 30, 2017, 02:21:12 pm »
You could try an SSR. As long as it can switch at the mains frequency and will automatically shut off at the zero crossing then it ought to work.
It's worse than that, it's physics Jim!