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Topic: Really universal soldering controller (Read 817793 times) previous topic - next topic

Re: Really universal soldering controller

Reply #5205
Use an 8 pin socket and connecor, and follow the connection schematics on page 1, even if you find them not logical. They work. All irons can be connected on the same 8  pin receptacle. It is true that the T210 and T245 are connected differently electrically, but I assure you this is correct.

that's why most users change the original connector with GX16-8p or GX20-8p as it is into docs from 1st page

I appreciate both of your responses. The bit of information I was missing was that the intention is for the JCB-style connectors to be replaced with alternative ones that are wired up to be electrically compatible while the original ones are not. That clears up my question and the documentation makes sense to me now taking that into account.

Thanks!

Re: Really universal soldering controller

Reply #5206
I appreciate both of your responses. The bit of information I was missing was that the intention is for the JCB-style connectors to be replaced with alternative ones that are wired up to be electrically compatible while the original ones are not. That clears up my question and the documentation makes sense to me now taking that into account.

Thanks!

You're welcome. Please make sure to use good quality connectors. I use Amphenol T 3527 100 and Amphenol T 3524 501. Available at Mouser.

Re: Really universal soldering controller

Reply #5207

The values to change are GAIN and C1, correct? so for C245 GAIN = 87, C1= 41.85, for C210 GAIN = 202, C1 = 122.94?

It is strange: When I change like above, C245 works as expected, same as original FW. But C210 still too hot by 25 degrees compared to the original FW. So maybe there are other parameters I need to change?
May be the time he changes to the  original  profiles, Catear could find the problem and I hope he will keep the alignment ability

 

Re: Really universal soldering controller

Reply #5208
Changing gain won't do anything. It is just an opamp paremeter. It, along with the offset parameter, just regulates the amplifier so that
it gives 0-3V to the MCU's ADC. This gain and offset are then excluded from the calculations, and we get millivolts->temperature or resistance->temperature transformation.

Grounding considerations

Reply #5209
In my unisolder build I'm using an E-I transformer to step down 120VAC mains to 24VAC to supply the PCB. Based on the available documentation it looks to me like the secondary of the transformer is intended to be floating, though I've not seen that stated explicitly anywhere.

Is that indeed the intention, or should the secondary be ground-referenced? If it should be floating, what'd be the failure mode to expect if isolation between primary and secondary was to fail for some reason?

Thanks!

Re: Really universal soldering controller

Reply #5210
Trimmer MUST be set to show as close to 10 ohms as possible, when calibrating. When it is away, the amplifier gain is not set properly.
Also, you must test the current sources. For surrent of 128 in the calibration menu, the current between SenseA/SenseB and Vout- shoud be as close to 382.8125uA. If it is off by more than 1% (ideally if shoud be within 0.1%, if the voltage reference and the resistors are the correct one with 0.1% tolerances and the current source mosfets and opamp are not fake ones), then the current sources themselves are not sunctioning propery.

Although the current sources are not that important for thermocouple measurement (maybe 1-5 degrees), they directly impact the resistive sensor measurement and along with amplifier gain setting the end result can be way off.

This is very important indeed. To illustrate: I re calibrated with two 0,1% 10 ohm resistors. One resistor gives a R: value of 1001, the other 997. When I take this as the calibration, the difference between the two irons is only 6 degrees instead of 25 degrees with my previous calibration value that I changed slightly when calibrating with pure lead.

This means to me that calibrating with melting temp can give a good result for a specific tip, but it will throw off the calibration of other tips/irons. The best thing is to accept a small offset per tip, and make sure you calibrate as close to R: 1000 as possible for most consistent behavior.

Re: Really universal soldering controller

Reply #5211
In my unisolder build I'm using an E-I transformer to step down 120VAC mains to 24VAC to supply the PCB. Based on the available documentation it looks to me like the secondary of the transformer is intended to be floating, though I've not seen that stated explicitly anywhere.

Is that indeed the intention, or should the secondary be ground-referenced? If it should be floating, what'd be the failure mode to expect if isolation between primary and secondary was to fail for some reason?

Thanks!

Yes, this is intentional. The EARTH from tha mains must be only connected at iron's connector to the outer shell and some of the power lines of the heater, be it - or +. On two heater devices (tweezers etc) it is even connected arbitrarily to the heater 1 - or heater 2 -. This is why some SMPS are no good for this project if you want EARTH on your tips.

For example, the TC signal on C245 is connected in a way that gives negative voltage in respect to earth. It sould be connected also to give a positive signal (like C210), but when connected to give positive, the sensor appears like in series with heater and all the noises from heater power switching penetrate the measurement which the firmware must filter afterwards - look at the PC software ADC graphs on C245 and C210 - on C245 it is has almost no noises on it, and on C210 there are nasty peaks that have to be fighted by software filtering. This is fundamental difference between C245 and all other integrated heater tips with series thermocoule. On my controller, C245 has the best possible regulation exactly because there's no noise on the TC signal.

And the failure mode - the box, if metallic, is connected to earth, and the iron, if connected properly, is connected to the earth also. So there aren't safety isuues with earthing. The iron's stand should also be connected to the earth/enclosure if made out of conductive material. The controller itself is not connected to the earth - that's why there's separate pads for the mountung bolts on the PCBs, which are not connected to the rest of the PCBs.

Re: Really universal soldering controller

Reply #5212
This is very important indeed. To illustrate: I re calibrated with two 0,1% 10 ohm resistors. One resistor gives a R: value of 1001, the other 997. When I take this as the calibration, the difference between the two irons is only 6 degrees instead of 25 degrees with my previous calibration value that I changed slightly when calibrating with pure lead.

This means to me that calibrating with melting temp can give a good result for a specific tip, but it will throw off the calibration of other tips/irons. The best thing is to accept a small offset per tip, and make sure you calibrate as close to R: 1000 as possible for most consistent behavior.
The ideal effect can be obtained by using my firmware. First calibrate with 10r, and then adjust c1 so that each iron rod can melt the solder at the same temperature

Re: Really universal soldering controller

Reply #5213
The ideal effect can be obtained by using my firmware. First calibrate with 10r, and then adjust c1 so that each iron rod can melt the solder at the same temperature

I agree in theory, but somehow I cannot get the same result with C210 on your FW compared to Sparky FW. Changing C1 on C210 does not seem to have much effect.

I will patiently wait on your FW with the standard iron profiles based on the latest Sparky FW. I will say that you did a really great job on the rotary encoder code. It is much better.

EDIT: I was too careful I guess, because changing C1 to 145 did the trick. Both C245 and C210 now melt at the correct temp

Re: Really universal soldering controller

Reply #5214
I agree in theory, but somehow I cannot get the same result with C210 on your FW compared to Sparky FW. Changing C1 on C210 does not seem to have much effect.

I will patiently wait on your FW with the standard iron profiles based on the latest Sparky FW. I will say that you did a really great job on the rotary encoder code. It is much better.
Under the original firmware parameters, my 210 has never been accurate. I don’t think I need to look forward to the effect of recompiling, because it will have the same effect as directly modifying the value on the menu.

Re: Really universal soldering controller

Reply #5215
Under the original firmware parameters, my 210 has never been accurate. I don’t think I need to look forward to the effect of recompiling, because it will have the same effect as directly modifying the value on the menu.
Sparky just mentioned above for the differences b/n cartridges, did you bridge some part of his FW

Re: Really universal soldering controller

Reply #5216
Sparky just mentioned above for the differences b/n cartridges, did you bridge some part of his FW
No, I haven’t changed much of the key things

Re: Really universal soldering controller

Reply #5217
No, I haven’t changed much of the key things
in that case, is it possible for the FW to be heavier the time it needs to calculate ( work ) on C210


Re: Really universal soldering controller

Reply #5219
Hello Everyone,

I am compiling a database of JBC handles and cartridges. As this database should contain tc and heater data, I'm currently sifting through the internet to find such data.
The iron.c seems to have a fair amount of data on JBC handles and I guess i could calculate the tc and heater resistance from this data. Can someone quickly tell me how I can calculate these two data from the iron.c array values?

Thanks very much!