Stefan Wagner

@danielrev If the input voltage is incorrect, you can tweak the calulation formula in the sketch. Which firmware version do you use?
It should work with 100k / 470R as well. The 2n2 shouldn't be much bigger, otherwise the settle time will increase too much. The capacitor can practically only discharge through the 10k resistor. If you choose it to be much smaller, it will no longer smooth out the noise as well. But you have a little leeway.
I always lack the time to create videos and writing documentations in a non-native language isn't so easy for me. But the calibration shouldn't be too difficult. You need a soldering tip thermometer, select calibration in the menu and then simply follow the instructions on the OLED.

danielrev

@wagiminator the tip temp is working ok just the input voltage detection is not so linear .maybe my resistor not so precise ?
Oh ,can i make resistor gain sett to 100k and 470ohm ? is 2n2 cap value is critical ? maybe you should make video or documentation how to calibrate the station on newest firmware .
anyway i really pleased with the station performance :)

Stefan Wagner

@hunghanhiuiuiu I am impressed! Your self-built soldering station looks a lot more professional than the commercial device to the right ;-)

Stefan Wagner

@stephen.mcmxiv The MOSFET should work fine without any further changes.

Stefan Wagner

@danielrev I also have a couple of clone chips. They basically work quite well, but the internal temperature sensor has probably been saved. Does the temperature detection of the soldering tip work? Is the displayed value for the input voltage completely wrong or only imprecise?

Hung Dao

@wagiminator I finished it. Haha

Hung Dao

@stephen.mcmxiv Just try it, it won't damage your chip.  I took the mosfet from the main computer to work perfectly.

stephen.mcmxiv

Hi Sir, will IRFZ44N work with this design? If possible do I need to change anything on the circuit like resistors, capacitors, etc.,?

danielrev

@wagiminator found the problem yesterday . its the mosfet who leaking causing temp reading changing when input voltage increased . but still the internal chip temp and voltage reading not good .i got my atmega chip from local online marketplace ,surely its clone chip i think .

Hung Dao

@wagiminator Thanks. All thanks to your great design.  I've been following you for a long time and saw a lot of your good designs.  one more time thank you very much!!

Stefan Wagner

@hunghanhiuiuiu I love it, that's the real DIY !!! ;-)

Hung Dao

@wagiminator haha.  I don't make the board with CNC.  I made the most rudimentary method, printed out a sheet of paper, placed it on the board and ironed it with high heat, then etched with FeCl3.  :)).  The oldest method of making circuits, because my place is in the countryside, there are no modern machines to do.

Stefan Wagner

@hunghanhiuiuiu Cool!!! Did you make the boards with a CNC mill?

Hung Dao

@wagiminator haha I do it by hand so it's very bad, and there is only one-sided circuit so I have to make 2 boards

Hung Dao

@wagiminator  Sure! I posted a picture of my change! I am using version 1.7 of the original firmware! It is amazingly stable in temperature, changing only 1 degree or not! Thanks for creating it! Also I use all the old components like Mosfet taken from the computer motherboard, opamp ... etc .. completely cool not hot !!

Stefan Wagner

@hunghanhiuiuiu Can you tell me what exactly you changed at +IN1 so that it works with the 907/936 soldering iron? This is definitely interesting for other users too!

Stefan Wagner

@hunghanhiuiuiu Congratulations! Which firmware do you use? With version 1.7 of the original firmware you have to adapt line 890 of the code.

Stefan Wagner

@danielrev Please first check the supply voltage (VCC) of the ATmega with a multimeter. You can measure it at the output of the voltage regulator or at the VCC pin of the ICSP header. What is shown? Does VCC change when you increase / decrease the input voltage? All ADC measurements are dependent on a stable supply voltage, which should always be between 4.9V and 5.1V. Can you tell me where you bought your ATmegas?

Hung Dao

@wagiminator Hi! I did and it works perfectly with arduino nano v3 and soldering hand 907/936, just changing a little bit of input "+ IN1". By the way, let me ask about the voltage divider R12 and R13, I got the wrong voltage displayed on the screen. How to get the correct voltage value without changing the resistor value? thank you!

danielrev

@wagiminator Hi Stef,after change to new chip i got pwm now . The switching circuit work ok but there is new problem .
Problem no 1 : the reading of input voltage doesn't matchup with the reading on the screen .
no2 : when i use 12-14 volt input i got good temp reading ,but when i increase the input voltage the temperatur is raised even more for example when i use 12v and temp settle on 320 the i raise to let say 16v ,i got 360 read .
no 3 : internal chip temperature is inconsistent betwen power up and the temp doesnt make sense at all .

Any thing that i should check ?

Stefan Wagner

@Softlink The job of D4 is to limit the voltage between GATE and SOURCE (which is P+) of the MOSFET, not between GATE and GND. If you were to switch the diode between GATE and GND, then it would be impossible to switch on the MOSFET completely. Remember that when the MOSFET is fully on, the voltage between SOURCE and GND is 24V. If you were to use the diode as you have described, then the voltage between GATE and GND would be 18V and thus the voltage between GATE and SOURCE would be negative. The MOSFET would then be switched off again. But this state would not even come about, the MOSFET would only be switched on "a little" and probably overheat.

Softlink

@wagiminator thanks, can you please check if D9 the anode is correctly connected, I feel that the anode should be connected to the ground and not p+. I ideal of this zenner is to limit the voltage at the gare to a max of 18volts and if anode is connected to the ground the zenner will be still in reverse biased. I do remember reading in the replys by you above that the D9 be removed as is incorrectly connected and the power supply be limited to 19volts. Please clarify. Thank.

Stefan Wagner

@Softlink Ah yes, that's why the capacitors couldn't discharge and kept the voltage on. The firmware supports both, direct control (on/off) and PID (PWM). You can choose that in the menu. D4 is connected the right way around, Zener diodes are usually used in reversed biased mode.

Softlink

@wagiminator just another clarification as the mosfet gate is connected through Q1 and to D9 of the arduino and D9 can facilitate pwm signal, does this iron make use of pwm to control voltage output by reducing voltage to control temperature or just shuts off the output totally as still i do not have the t12 tip and so am not able to verify that, hope these are not silly questions. Thanks Regards.

Softlink

@wagiminator@wagiminator thanks sir I have figured out the issue, untill now I do not have the t12 bit so I was testing without the load the issue resolved as soon as the load was introduced. Another observation the anode of Diode D4 18volt zener may be incorrectly connected, insted of p+ the anode should be connected to the ground. Kindly look into it and advise

Stefan Wagner

@Softlink If the input of the OpAmp is 0.6V then it is normal for the output to be 5V as the gain factor is 201 but the output of the OpAmp cannot be higher than the supply voltage. So the OpAmp seems to be working normally. So the question is why the input is at 0.6V. Due to the diode D2, the input voltage at the OpAmp can only be a maximum of 0.6V, so it is quite possible that the voltage at P + is even higher. Since I don't know what exactly you have connected to P +, I can at most assume that the capacitors C8 and C13 cannot discharge.

Regarding the question of component selection: It's pretty simple. Whenever possible I use suitable components that I already have lying around. At least for me this is usually the cheapest option ;-)

Softlink

@wagiminator
Just for my knowledge incase only one op amp was required by this project why was 333 not used instead of 2333 probably cheaper and less circuitry?

Softlink

@hunghanhiuiuiu
Thank you sir for your reply.

Softlink

@wagiminator Dear Sir thank you for your reply I do suspect something wrong but am not able to figure it out, when I remove the p+ line feeding the signal to +in1 (that is physically remove it) the output at out1 drops to 0volts but as soon as p+ is connected and t1 is on at that time mosfet is off but still there is about +0.6volts on p+ but the out1 immediately becomes 5volts. Is there a way by which I can check if opamp1 is working ok.

Stefan Wagner

@Softlink Hi,
the second OpAmp is not in use. As Hung Dao correctly pointed out, an unused OpAmp should not be left floating because it could induce noise or even get damaged. That's why the resistors are there to keep the second OpAmp in a stable state.
If the input of the first OpAmp is exactly 0V (not only close to), then the output shouldn't be 5V. It should be near 0V (it can not swing to exactly 0V, but close to it). Please check if everything is wired correctly.

Stefan Wagner

@hunghanhiuiuiu Hi, of course you can.

Hung Dao

@Softlink  as far as I read @wagiminator opamp 2 when the output is not going anywhere but just a feedback to reduce noise.

Hung Dao

@wagiminator  Hi! Can you allow me to make a video of this project of you? I plan to do it on Arduino nano V3 and tips hakko 936! Looking forward to your feedback. Thanks

Softlink

Great project but could someone please explain in detail the working of the thermocouple amplifier. I do not understand the woking of opamp 2 when the output is not going anywhere but just a feedback. Secondly what should be the output of opamp 1 when the p+ pin is at 0 volts, I am getting 5 volta as the output of opamp 1 (at pin out1) is this correct?
I am not too technical but would like to understand, any related literature would also be helpful, specific explanation to this project would be deeply appreciated. Thanks.

Stefan Wagner

@hunghanhiuiuiu You can use the UI-Upgrade firmware, which can show the pwm-value. I personally prefer a display that is limited to the essentials (temperature and setpoint, I don't need anything else for soldering). Of course, you can also adapt the firmware to your liking.

Hung Dao

Great! If only the SolderingStation2_u8glib_v1.7.ino version showing % PWM would be perfect :)

Stefan Wagner

@danielrev I wish you success!

danielrev

@wagiminator i've tried almost anything on your github .let see if new chip make any different :)

Stefan Wagner

@danielrev The problem seems to be with the ATmega. Either there is something wrong with the software (which version are you using?) or the ATmega has a bug (which would be very strange, at least I didn't have that yet).

Stefan Wagner

@mart.maiste Hi,
a 5.1V Zener diode was used for the ATtiny13 soldering station. It limits the voltage at the input of the OpAmp to around 5V so that the OpAmp is not damaged when the heater is switched on. This would of course also work with the ATmega soldering station. Since the voltage that the thermocouple generates is significantly less than 0.1V, I have chosen another option here. A normal diode has a forward voltage of about 0.6V. With the circuit used here, the input voltage at the OpAmp is therefore limited to 0.6V. This has the advantage that after the heater is switched off, the voltage at the input corresponds more quickly to the voltage generated by the thermocouple. I hope that answers your question.
Greetings, Stefan

Märt Maiste

@wagiminator The diode between the input (+IN1) of the opamp and grond is reversed and perhaps another type compared to most other designs, including on your attiny13 soldering station. Can you elaborate on this design choice?

danielrev

@wagiminator Yes ,it goes straight climbing until error when i apply power .but when i disconnect resistor on transistor base and connect alternating to 5v and gnd it behave as it should . and when i apply heat to the tip w/o mosfet circuitary i got temp reading . maybe i got defect chip ?

Stefan Wagner

@danielrev If D9 is LOW (0V) then the MOSFET should be switched on and the soldering iron should be heating. So the question is, why doesn't the ATmega turn off the heater? What temperature is displayed on the OLED? Does the temperature exceed the setpoint?

danielrev

@wagiminator Hi Stefan ,i already check the voltage and the result is on pin d9 it read 0v ,on the gate it read whatever voltage i apply to the board .for the diode i use ss240 and mmbt3904 on buffer transistor

Stefan Wagner

@mart.maiste Hi, the second channel is not used. The resistors are there to prevent the second channel from floating.

Märt Maiste

Hi, has the second channel of the op-amp with the R10-R11 voltage divider any specific role or can they be omitted?
PS! Thanks for sharing the project!

Stefan Wagner

@danielrev I can't imagine the fuses being the problem when everything else is working. Does it show a rising temperature that exceeds the setpoint? Please do the following: remove the soldering iron, switch on the station and use a multimeter to measure the voltage at PB1 (D9) of the ATmega (should be 5V) and at the gate of the MOSFET (should be 0V) with respect to GND.

danielrev

@wagiminator Hi ,my firmware is correctly loaded because all the function is ok except the mosfet . already try different mosfet and swapping other component but still no luck . maybe it fuses issue is the problem here .

Stefan Wagner

@danielrev Is the firmware running on the ATmega and is something displayed on the OLED? If not then this is normal, the firmware in the ATmega must actively switch off the MOSFET. If the firmware is running, the MOSFET could be defective, perhaps due to a static discharge. If the ATmega is from an Arduino UNO, then it should actually have set the correct fuses, provided the bootloader is still installed.

danielrev

@wagiminator Hi Stephan , i got some problem with mosfet always on when i power up the circuit . i dont see anything wrong with the component i used . for the mosfet i use stu432s . or it because the atmega i used is pulled from arduino uno so its not come with correct fuse or something ?

Stefan Wagner

@danielrev As far as I can tell, the station should work fine.

danielrev

@wagiminator Hi , what do you think about this https://oshwhub.com/222465.255411/8838-ban-pmos-atmega328p-han-tai ?
its based on your project but it says can use p channel mosfet just by changing one value of the code .
already try it but still no luck .
can you take a look ?

Stefan Wagner

@danielrev Hi, I think designing a new board and adapting the software is a lot more work than ordering a couple of n-channel MOSFETs. I suspect an electrolytic capacitor also works, but to be on the safe side it should be ratedfor at least 50V.

danielrev

Hi , can you make a version using p channel fet as switch ? reason is i have some left over in my drawer .
if not can i replace the 10uf cap on fet circuit with regular electrolytic ?

Stefan Wagner

@edcali Hi, your wiring is correct. Do not power the Soldering Station PCB, only the Arduino Nano! The ATmega on the PCB is then powered by the VCC line from the nano. You do not need a bootloader, but you have to set the fuses correctly. First you have to install the Barebones ATmega board definitions: https://github.com/carlosefr/atmega. Setup you Arduino Nano as an ISP: https://www.arduino.cc/en/Tutorial/BuiltInExamples/ArduinoISP. Then in the Arduino IDE go to "Tools -> Board -> ATmega Microcontrollers" and select "ATmega328/328p". Go to "Tools" again and select the following board options: Processor: ATmega328p, Clock: External 16 MHz, Programmer: Arduino as ISP. Then go to "Tools" and select "Burn Bootloader" (in this case it actually doesn't burn a bootloader but it sets the correct fuses). Now you can open, compile and upload the code.

edcali

Hey guys, if any of you may light me how to flash the micro controller ATmega328 U, it would be great, I am very new to micro controllers. As I understand I need to Burn the bootloader to Atmega 328 U firstly, in order to load the code.
Do I need to powered the SolderingStation PCB and the Arduino NAno board as same time? or just  I connect the 6 pins(SolderinStation ICSP) to the Arduino Nano pin Out.?
These is a scheme I've been working considering I am very new to electronics. Sorry in advance if the question are silly. :)

edcali

@wagiminator Thank you Stefan. I am so happy that you simply don't ignore my messages. They are so silly for someone like you. My knowledge is very basic. I am going to comment that line.
Thank you. Right know I studying how to flash the Atmega328 U. Burn the Botloader. etc. I am going to post a question about here. If you keep helping me it would be great.

Stefan Wagner

@edcali Hello, thanks for the hint. You are of course right, a void function does not return any values. You can either delete the line with the "return" or simply ignore the warning. I should activate the compiler warnings in my Arduino IDE, then I will also notice such errors ;-) I will fix the error in the next software version.
Greetings, Stefan

edcali

@wagiminator Hi, Stefan! Finally many parts have came from Asia. I got a few Arduino's nano to test the code, compiling and upload. I upladed  to the board the 1.7 version of the software with success, But I got this warning!
// input tip name screen
void InputNameScreen() {
that's a void funtion returning a value, As far I know a Void function can not return any value.
-------------------------------------------------------------------------------------------------------------------------------------------------------------
C:\1\ATmega-Soldering-Station-master\software\original\sources\SolderingStation2_u8glib_v1.7\SolderingStation2_u8glib_v1.7.ino:802:10: warning: return-statement with a value\, in function returning 'void' [-fpermissive]
   return value;
----------------------------------------------------------------------------------------------------------------------------------------------------------------
Is this a problem, or I just Ignore?

Stefan Wagner

@Adrian Gałązka  I wish you success !

Adrian Gałązka

@Stefan Wagner  Thanks for answer , In the next month I will try to do

Stefan Wagner

@Adrian Gałązka  I haven't tried it myself, but another user has. It works with the original software version v1.7. To do this, you have to comment line 173 in the source code and uncomment line 174.

Adrian Gałązka

Hello I like your project a have quetion you tryed give display oled 1.3" ,you think there will be no problem without a program correction.

Stefan Wagner

@edcali Hi and yes, v2.7 is the latest board revision.

Stefan Wagner

@stephen.mcmxiv Hi, the circuit can also be built with an Arduino Nano. There are also THT alternatives for all components. With the OpAmp you have to rely on the LMV358, the OPAs are only available in SMD as far as I know.

edcali

@wagiminator Thank you so much, You always answering kindly. We are talking about the SolderingStation_v2.7? lastest version.

stephen.mcmxiv

Hi Sir Stefan, thank you for sharing this nice project. Forgive me to ask this noob question. Can this be made using through hole components instead of SMD ones? Also, can I use Arduino Nano, Uno or Mini with this project?

Stefan Wagner

@edcali Hi, the problem is fixed with the latest board revision.

edcali

@wagiminator Hi, Stefan, I had to give away a few months ago because a lack of knowledge to build this project, but I am back and this time I'll go further until I finished it. Wondering if you fixed or corrected the problem (the overheating of the 4148 and the 18V zener) up to 20 volts.
Is there a new version of the PCB fixed? Before I order the the PCB.

Stefan Wagner

@Akram Mamadaliyev  Hi, I don't have a 907 handle, so I can't tell you anything about it. As far as I know, the temperature measurement works differently there, so that it does not work with this soldering station without modification.

Akram Mamadaliyev

@Dipak Kumar Maity
Hello! Nice work, How you connect iron 907, can you send circuit diagram. Thank you.

jettetsoi

@wagiminator Thank you very much. I will check the circuit again. I think I did some wrong.

Stefan Wagner

@jettetsoi Hi, I haven't had any problems with this board version yet. It is normal for R5 to get warm, but it shouldn't get hot. Please check whether your resistor is rated for 0.5W. If this is not the case, then take a 2k or a little higher. A bit of background knowledge: R5 limits the current to the gate of the MOSFET. Aside from short spikes when the MOSFET is turned on (then some current flows from capacitor C7 to the gate), the resistor is mainly stressed when the MOSFET is turned off. Current then flows from the input (up to 24V) via diode D1 through R5 and transistor Q1 to GND. If you include the voltagedrop at D1 and Q1, up to 23V drops at R1. The power loss is then U² / R = 23² / 1000 = 0.53W. This loss is converted into heat. If you increase the resistance, the power loss and the heat dissipation decrease. However, the switching time of the MOSFET is longer and the efficiency drops somewhat.

jettetsoi

@wagiminator Is the over heat problem fixed now? I made a board with version 2.7. I found a strange problem. The 1k (1206) resistor is very hot no matter I use 24V or 19V input.

Stefan Wagner

@keiser1080 Hi & thank you! That should work fine with the modifications you mentioned. All components also run at 3.3 volts, the output voltage of the operational amplifier is also below 3V for the temperature measurement. I wish you every success with your project and I would be happy to hear about the result.

keiser1080

Hi,

Thanks for your work.
It's a very nice solder station.
It's the clearest schema and the  most doccumented i have found in the internet.
For learning purpose I want to do my self soldering station based on an alterned version of your design.
I want to use an esp32 in order to use micro python.
In order to work in 3.3V power and and logical level.
Do i need to change other thing than the following componant ?
U2 = ldo 30V to 3.3V 1ALD1086DT33TR
R13 = 7.5K 0603WAF7501T5E
D3 = 3.3v zener diode MM1Z3V3

Stefan Wagner

@mclj39 Hi, thank you. Unfortunately, I don't have the time to put kits together and sell them.

mclj39

Hi. nice job. Have you considered selling kits?

Stefan Wagner

@mclj39 Hi, that is hard to say. In particular, the costs for the components depend heavily on the order quantity. For example, I bought the ATmegas in a package of 20 for less than a dollar each, including shipping. If you were to buy them individually, you would have to pay twice as much. If I had to make a rough estimate I'd say under $ 15 for everything.

mclj39

How much money would the complete kit cost?

Stefan Wagner

@danielrev Forget what I told you about the new UI version of the firmware, it uses a different OLED library. If you want to use this firmware version with your OLED you can ask the developer of this version who also developed the library.

Stefan Wagner

@danielrev In the v1.6 firmware you have to change line 171 to the following code:
U8GLIB_SH1106_128X64 u8g(U8G_I2C_OPT_FAST|U8G_I2C_OPT_NO_ACK);
(In the new UI versions of the firmware you have to find the corresponding line with U8GLIB_SSD1306 and change it to the line described above)
It might be necessary to change the i2c pullup resistors R3/R4 to 10k as in the latest board revision.

danielrev

Hi , I have problem when connecting 1.3" oled screen ssh1106 .
It just displaying white all over the screen .
Is current firmware only support 0.96" or something ?
im on V1.6L+ firmware right now .

Stefan Wagner

@oleg.tchurilo Hi, does it came from here: https://oshwhub.com/Oleg533/soldering-station-v2-5? Next time you publish my projects elsewhere it would be fine if you stick to the license! Canceling out any attribution to the original designer is a bad way to support the open source community. However, I made some tests and I found the same problem for voltages above 20V in the current board revision (I didn't noticed it before because I'm using a 19V power supply). So there is a design error in the combination of the 4148 and the 18V zener. I will work on this problem for the next version, until now you have two possibilities: either you use only 19V or you have to desolder the zener (with a risk of damaging your MOSFET).

oleg.tchurilo

Hello, I made one according to yours. There is a problem, that is, the diode 4148 of the booster circuit is very hot. Is this normal? If it is abnormal, where is the problem? Hope you can help, thank you very much.

danielrev

@wagiminator Ok not big deal ,the only reason i ask about that it just because i don't have arduino board on hand and the current situation made little bit hard to buy something . i have some atmega328 chip and ftdi programer but no usbisp to burn bootloader to the chip .

Stefan Wagner

@danielrev Hi Daniel, unfortunately I'm not familiar with the STM32 microcontrollers. My brain is currently only working on 8 bits ;-) Maybe I'll dive into it in the future, but to be honest I can't see any advantage by now (at least for my simple projects). But as far as I know there are many stm32-based soldering station projects around. I'm sorry I couldn't help you much.

danielrev

Nice Project Stefan !
Could you make a version with stm32 based micro ?

Stefan Wagner

@xxoops You're welcome ! ;-)

xxoops

@wagiminator Thank you.

Stefan Wagner

@xxoops Hi, OPA2333AIDR should also work, actually it's an even better OpAmp.

xxoops

Dear Sir,

Could OPA2330 be replaced with OPA2333?

Regards,

Stefan Wagner

@disha4care Hello, I hope you are healthy. Can you tell me how you connected the 907 handle to the board?

Stefan Wagner

@stephen.mcmxiv You're always welcome!

stephen.mcmxiv

@wagiminator Thank you so much for responding. You've been very helpful and I really appreciate it.

Stefan Wagner

@stephen.mcmxiv... just to be on the safe side, although the 3904 is only 40V.

Stefan Wagner

@stephen.mcmxiv A small correction for the transistor: it should be rated for at least 50V!

Stefan Wagner

@stephen.mcmxiv Hi, I'll try to answer your question but keep in mind that I can't guarantee things that I haven't tested. Your MOSFET will not work because it's a p-channel type, you need an n-channel MOSFET. The LMV358 in my design is a rail-to-rail OpAmp, the LM358 is not. Apart from that, it could still work because the output voltage is below 3V. I would still advise against it because I do not know how the LM358 behaves in this circuit. You can use any NPN transistor which is rated for at least 24V, I think yours is only 12V.

stephen.mcmxiv

@wagiminator Simple yet effective. I am wondering of I could use the following components as alternatives:

IRF4905PBF for the mosfet
LM358P for the op-amp
2SC3356 or any cheap NPN transistor.

Thanks again.

Stefan Wagner

@stephen.mcmxiv Thank you, although this is just a simple soldering station with a few cheap components. I think there are more sophisticated ones.

stephen.mcmxiv

Sorry, I wasn't reading. This really does have calibration features. By the way, thank you for sharing this project. This is the best of all the soldering station controllers I found.

stephen.mcmxiv

This a great project! By the way, does this have a calibration feature?

Stefan Wagner

@dinidudius Thank you for your feedback ;-)

dinidudius

THANK YOU .IT IS COOL

johngr

@wagiminator thats correct..

Stefan Wagner

@johngr Of course you do, the whole project is much better now than it was before. John Glavinos, correct ? (saw it on the photo you provided)

johngr

@wagiminator i dont mind of course,but i didnt do anything to deserve the honnor,you did all the job of course..

Stefan Wagner

@johngr There are a lot of version numbers left for your ideas ;-) By the way, can I mention your name in the disclaimer of the source code as you made a valuable contribution to the software by providing a working PID that I was unable to do.

johngr

@wagiminator i agree.maybe its time for v1.3 which has everything i think now.until i come up with something else..hehehe.(joking)..

Stefan Wagner

@johngr Hi, I have tested the new PID settings: 100% stable with my 19V power supply, excellent!!! Maybe we can leave the beta-state of v1.3.

johngr

 @wagiminator  it was arduino ide's fault after all..reinstalled all libraries again and everything works fine now..sorry for the trouble caused you..with the new pid settings i found it works almost perfect. and im powering it with 19v now..

johngr

@wagiminator exactly.thanks for your effort. to tell you the truth when you released the v1.3 when i tryied to send it to arduino it didnt compile and had to uninstall and reinstall arduino ide and then compiled ok.my libraries werent affected though,thats what the installer told me.maybe something is missing from the ide enviroment??

Stefan Wagner

@johngr Just checked sleep function with v1.3 and it worked like a charm. Sleep function is working for you with v1.2 but not with v1.3 ?  Mmmh, I have to sleep over the problem ...

Stefan Wagner

@johngr OK, I didn't test the sleep function in v1.3, so I must have done a mistake somewhere. I will check it.

johngr

switched back to v1.2 to check if my hardware is working ok and works fine but without the new features you added of course..

Stefan Wagner

@johngr Mmmmh, this is strange. It works perfect for me. It seems like a wrong temperature calculation. Maybe I have to add a fourth calibration point somewhere around the sleep temperature ...

johngr

and the sleep temperature doesnt work either. it should keep it to 150c until it detects movement and start rising again but the iron has become cold.

johngr

one thing i noticed is that when the controller enters sleep mode and temperature starts to drop it doesnt show correct temperature as it drops.for instance the temperature has droped to 50c but the display shows 190and responds very slowly..

johngr

best results i could find are with these settings,almost rock solid. sometimes jumps 2-3 degrees  but i think its because of noise of opamp and not pid settings. try them and tell me what you think.
double aggKp=11, aggKi=0.5, aggKd=1;
double consKp=11, consKi=3, consKd=5;

johngr

im still experimenting with the pid code to find even more accurate results,even so it is more accurate than another soldering iron project that i built and testing also.soon i will give you improved pid settings i hope..

Stefan Wagner

@johngr Hi, I tested the PID and it works much much better, almost perfect. The variation with my 19V power supply is not more than +/- 5 degrees and most of the time it's absolute stable now. Good job!!! I did some minor changes to the direct control and to the stabilization of the displayed temperature. I upload the changes as beta2.

johngr

@wagiminator i just discovered that these pid settings dont work well with 19v supply(the temperature varies +-10). instead with 24v works very good.(very stable and sometimes +-3)

Stefan Wagner

@johngr Hi, this is looking great!!! The code checks the voltage on start-up and sets the settle time according to it. So maybe you try it again with 19V from the start. Or I change the code in the way that the settle time is permanantly changed according to the input voltage. I will try your PID parameters. For the noise of the OpAmp: this might be reduced a little bit on the pcb as the lines are shorter and not that much subject to interference.

johngr

here's a photo of my controller https://photos.app.goo.gl/2TtWHCuhRAvYgygm7

johngr

@wagiminator the power supply  im using is a universal laptop power supply (MW brand - i think is a good one ) with selectable via switch output 15v - 16v - 18v - 19v - 20v - 22v - 24v. when i power it with 24v it is almost rock solid but when i power it with 19v i see variations +- 10c. for instance if i set temperature to 380c i see the led i added to monitor the heating process i told you before lits up until it reaches 380 then led stops the temperature overshoots untill 390 then temperature starts to lower until it reaches 370 then led lits again and so on. the procedure im lowering the voltage is while its working at 380c im changing voltage switch to something else 20v for instance and wait a little for the temperature to stabilize then im starting to see variations,its something like the circuit is more ''sensitive'' to display temperature variations.another thing i noticed is that if i move around the controller on the desk these variations may stop so it might be noise that the opamp receives,im always powering it with 24v so i dont have any problem. for the display dimensions it doesnt really matter because i built the controller  not with the pcb you provided but with an arduino nano and a pcb i designed to hold the rest circuit(opamp-mosfet-regulator) and smd components. at some time later i will order from jlc pcb the exact pcb you designed since it is much more compact and small. as long for the pid controll i think im in a good way. i've played a lot with the settings and found satisfactory results.
double aggKp=10, aggKi=0.5, aggKd=1;
double consKp=10, consKi=3, consKd=5;
but it needs some more tweeking..

Stefan Wagner

@johngr Hi, thank you for testing. With the PID I never found good parameters, maybe you will. 1.3 inch display should work as well but maybe it won't fit directly on the board. That's interesting with your power supply. Of course I tweaked all the parameters to work with my supply and so I don't have any problems. Does the displayed temperature over- or undershoots or both? With how many degrees? Does it also jumps when you're measuring with a tip thermometer? Did you start with 24V and lowered the power while the station is on? So many questions ...

johngr

 @wagiminator
been testing with the beta you released.it works just fine as the previous..the pid needs tweeking. i will have to experiment with it until i find satisfactory results.the additions are perfect..will this controller work with the 1.3 oled display that uses the same driver chip? i ordered some but didnt arrive yet to try.one more thing,if i lower the supply voltage below 24v i see variations of temperature on display every time the mosfet applies power to the heating element.(i can see that because i connected a led + resistor on the output to the soldering iron) to have a visual indicator when the power is applied to the iron..

johngr

wow..ok.i will try it today...thank you..i''ll keep you informed..

Stefan Wagner

@johngr Soooo, I had nothing else to do...;-) I uploaded a new beta with your requested features including a selectable PID-control. You still have to tweak the PID tuning parameters in line 86/87 of the code (maybe you have more luck than I do with the PID). You can select a different main screen in the setup menu as well. However, I highly recommend using a 19V power supply rather than a 24V one to get absolute stable temperature readings.

johngr

i dont think i have major problems, rarelly i see some variation of temperature on screen about 3-5 degrees but this i believe is because of the on-off of the heating element when the mosfet applyies power to it. its normal to see this on the screen.thats why i suggested the pid control. i understand that with pid control there is going to be an overshoot until it settles to a stable temperature.however ''as is'' this project is much better than many other i have tryied even and commercial one's..if there was an easy way to implement pid controll that could be enabled or disabled from the menu it would be interesting to try..of course you know better..if you think that its going to affect the rest functionality..

Stefan Wagner

@johngr Thanx a lot for your testing !!! I will see what I can do to add more information to the main screen. My first implementations of this station included a PID control. However the results were not as good as they are now with the more direct control (at least for me as I have no problems with overshoots or unstable readings, but this may depend on the power supply you use; or a cheap OpAmp;-). If you have such problems I can tweak the denoising routines a little bit, if you don't have such problems than the PID would be no improvement, only a waste of memory and processing power.

johngr

beta works perfect after many days of use..many thanks!!!few ideas if you like to consider..how about adding on the screen if it fits what tip we currently use and voltage measurement if somebody wants to use it with batteries to make it portable since the pcb is small and can be fitted in a small housing and last pid controll,maybe selectable if it will be used or not from menu, of course im not sure if the arduino has  the ability to handle all these at the same time..anyway..you made a great project..thanks again for sharing ..

johngr

hello..i loaded the latest beta firmware you released.everything is perfect so far.i will keep you informed if i discover any bug.thanks..!!

Stefan Wagner

@johngr Hi, thanks for your testing. I'm happy when you're happy;-) I just forgot to catch the situation when you exceed the maximum number of tips; version 2 fixes that.

johngr

oops..now i just saw that you released another beta2 firmware..i will try it a.s.a.p. what improvements you did??

johngr

after a few tests with the new firmware one thing i have to say... congratulations!!!it works perfect!!! now i can change tips quickly and load the settings of each tip..at first i was having some issues with oscilations the readings were jumpy but that wasnt firmwares fault because i tryied the old again and the new and did the same,after adding some decoupling capacitors and replaced the opamp worked again perfect (crapy -fake opamps from ali express) ..and the menu you added makes perfect sense...great job!!!thanks again..i will post again after few days of testing..

johngr

@wagiminator wow..that was fast..of course.as soon as i get home cause im at work i will try it..thanks!!!

Stefan Wagner

@johngr Hi, I uploaded a beta-version of the new code with your requested features. As I only use one kind of tips I kindly ask you to be my beta-tester. I'm looking forward to your feedback

johngr

thanks for your answer.i think that this is the only thing that is missing because you cant take advantage the t12 tips (quick exchange) if you have to recalibrate again.and this is the point of the t12 tips to quickly change them.if this is implemented the project will be perfect in my opinion..

Stefan Wagner

@johngr Thanks for your comment. Adding a feature for storing different calibration values should be no problem. Maybe I will implement this in the near future, when I find the time to do it.

johngr

thanks for sharing this project..made it and it is working almost perfect.one question.when i change various tips calibration must be done again??is there a way to implement a menu that holds the settings from different tips we use so we dont have to calibrate every time we use different kind of tips??

Stefan Wagner

@disha4care Interesting, I didn't think it would work with 907 handles as well. But the performance should be better with T12 handles.

Dipak Kumar Maity

@wagiminator I have made it and it working Very wel with 907 handle, You are welcome most Sir

Stefan Wagner

@disha4care Thank you and have fun with it !

Dipak Kumar Maity

Nice and working