DIY JBC Nano

[jjoonathan]

The $1400 JBC Nano stations at work have me completely spoiled. Inspired by GreatScott!!'s JBC Mega (for lack of a better sizing term) here:

I'm going to try to make a DIY controller so that I "only" have to buy the handles. Small difference #1: the 105 series nano tips only have a single tip/sleeve circuit to be shared between thermocouple measurement and power delivery (vs tip/ring/sleeve on the "mega"). No biggy; it's not like you could easily get accurate thermocouple readings during the power delivery phase anyway.

Small difference #2: the nano handles don't use standard DIN connectors, or at least not the ones I'm familiar with. Sure, I could chop them off and replace them like a barbarian, but I'd like to give the connector companies a chance at taking my money first. Towards that goal, I could use any help you can give in identifying them. My imagination says that the logo looks a bit like a stylized combination of "a" and "p", like amphenol, but I can't find any record of them using that symbol. It doesn't really narrow things down much on digikey either. Thoughts?

[Aigor]

You have to search for Unisolder , a complete soldering station which can use almost every tip in the world

http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=7218&sid=4f264d655725b6302aecfd573e35df8d

The only "tricking" part is define new tip into software.
take a look

[jjoonathan]

Thanks for the post, but it's not the thermocouple sensing, control loop, power or display driving that I'm hung up on, it's the connector. In the demo video it looks like they took the "barbarian" approach of chopping off and replacing the connector, which I am aware of as an option but am hoping to avoid.

[capt bullshot]

The logo is from Binder:
https://www.binder-connector.com/en/

The connector looks like the Bayonet IP40 series
https://www.binder-connector.com/en/products/subminiature-circular-connectors/bayonet-ip40/female-panel-mount-connector-6/#0909740002

[jjoonathan]

Thanks a million! That's exactly what I was looking for. Looks like Binder doesn't distribute through mouser/digikey/etc, instead they do it themselves. They do a very good job of it, too -- ordering was quick and painless, and I was very pleased to even find that the prices were sane ($6 ea). Given the high quality feel and low price of the connectors, I might even use them on other projects!

[TheAmmoniacal]

You have to search for Unisolder , a complete soldering station which can use almost every tip in the world

http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=7218&sid=4f264d655725b6302aecfd573e35df8d

The only "tricking" part is define new tip into software.
take a look

Anyone happen to have spare boards for this project?

[chickenHeadKnob]

Marco Reps has a similar project video here:https://youtu.be/GYIiOkr6x9o

These two have inspired the itch to try it on my own as well.

One difference between the two, Marco Reps targets the C470 250 Watt hand piece  and great Scott the t245. I am just learning  the jbc product line. The T245 looks like the general purpose one with the most variety in available cartridges. From the videos T245 reported 2.9 ohm heater resistance and 7.2 Ohms for the C470. The wattage of the JBC station for the T245 is  130W.

I want to use a DC switching supply and high side pfet for heater control like sparkyBG unisolder but his design is too universal with all the complexity that brings and uses a PIC, don't want. Which raises the question, is there some reason not to run DC through the heater, like electromigration or plating effects?. As far as I know the official JBC and the two videos both resort to running full wave AC but at least in the Reps case that appears for convenience only.

[mrjoda]

hi,
i have JBC CD 2B almost year at home. Absolutely love it best station and iron at world. C245 iron is little bit bigger than regular pen, for general purposes, you can use very big tips or small smd (i have 0,5mm smallest, waiting for offs from TME and i want to 0,3mm). C210 is micro pen for micro tips (0,1mm smallest).

[nowlan]

Just wondering how this, or the diy metcal compare to just buying a hako 888 or 951.

[mrjoda]

My colleague wants Hakko 951. Genuine one cost in europe 6-700€ per set with VAT. JBCs costs around 350. 

I need to improve my skills in programming, so i work on regulation  for those pen and T12. Based on STM32, AC supply with ZD. Thermocouple is amplified by LTC2051. Next step is optimalization of control loop. I can share if you want. It is only for fun project for me.

[dimkasta]

Interesting ideas.
Ideally I would prefer to choose an iron and build a minimal station that works nicely and is easy to maintain

The universal station sounds nice but the board does not look like something that you can easily tinker with in case of an issue.

[nowlan]

I am wondering if you can use a cheap halogen downlight transformer for 12v ac supply.
What is the (minimum) power these irons need? The downlights are 10,30,40w.

[chickenHeadKnob]

I am wondering if you can use a cheap halogen downlight transformer for 12v ac supply.
What is the (minimum) power these irons need? The downlights are 10,30,40w.

The official JBC irons have one major attraction: near instant heat-up and thermo regulation when applied to hard to heat situations. If you use such a wimpy power source you can get the iron warm in free air (slowly) but will find it totally inadequate  when soldering. Or essentially you duplicate the performance   of  a cheap ebay iron but are using an expensive handpiece - no point in that.

The maximum power delivered to the heating element is determined by its resistance, the supply voltage and %duty cycle. Ohms law is a bitch.

[dimkasta]

The OP made an interesting question though.

Would dc be such a big problem?

PWM would greatly simplify the circuit

[GreyWoolfe]

My colleague wants Hakko 951. Genuine one cost in europe 6-700€ per set with VAT. JBCs costs around 350. 

That's horrible.  Here in the US, the FX-951 is $236.45 USD at TEquipment.net without the EEVBlog discount.  No taxes for me as they don't have a brick and mortar location in the state I live in.   I am grateful I live here.

[mrjoda]

for example, JBC are using AC switching. This is capture from heater line on CD-2D.

BTW CD-2D has 2 regulation line so is it possible to use tweezers with CD-2D or two pens but with divided power and same temperature.

[Free_WiFi]

My colleague wants Hakko 951. Genuine one cost in europe 6-700€ per set with VAT. JBCs costs around 350. 

Scuse me,but where are you living ?
I mean here in italy ,i can get an standart Jbc soldering station for circa 400 euros .
Can you tell me some online shop from where i can get it cheaper ?
Thanks .

[kaevee]

My colleague wants Hakko 951. Genuine one cost in europe 6-700€ per set with VAT. JBCs costs around 350. 

Scuse me,but where are you living ?
I mean here in italy ,i can get an standart Jbc soldering station for circa 400 euros .
Can you tell me some online shop from where i can get it cheaper ?
Thanks .

Checkout the following link

http://www.vtech-smt.co.uk/Soldering-Equipment/JBC-Soldering-Equipment/Soldering-Equipment/CD-B-Soldering-station-for-general-purposes/

I bought one for 340 Euros from JBC as part of a bigger deal, but I paid 30% more for customs duty, but no VAT as the product was shipped to India.

Venkat

[stevelup]

I don't know where those crazy Hakko prices are coming from:-

http://www.dancap.co.uk/soldering/fx951pricelist.htm

[tivoi]

JBC china clone wave from
https://www.youtube.com/embed/3GMyvgiB-qk

https://www.youtube.com/embed/W_KQKP55DUw

how to add direct youtube link?
thanks

[fero]

Hi jjoonathan, how are you?
Iam also interested about building own station for jbc nano.
Do you have any news? Cable configuration/ resistor/heater?
Thx

[Xyphro]

Working on the same thing - already have running hardware and 80% software in place :-)

From what I see, the characteristic of the Thermocouple is quite close to a Type S thermocouple. The voltages are much lower, as the ones, that you'd get from a Type J/K thermocouple.

What I really wonder about, especially seeing other projects... The cold junction compensation is something, which cannot be done really well.
The cold junction is within the hand-pieces of the soldering iron (copper cable used from iron to connetor, but also the cartridge contacts seem to be of the same metal type.
Kind of proove of this theory:
I've dipped the iron into hot water. Initially the voltage was going up to 450uV, while then decreasing slowly to a much lower voltage, allthough the water was pretty constant at 83°C.

For that reason I concluded, that it'll not make a lot of sense to implement sophisticated cold junction compensation within the controller board.

Agree?
Or is there a mechanism present, on top of the thermocouple? e.g. measuring the heater resistance?

[Xyphro]

About the question of the cable configuration:
When you open the Binder connector, you'll see 4 terminals are connected.
2 are short circuited within the connector - GREEN. Green is connected to the TIP and to the metal ring to sense standby
1 Terminal is Red - Red is the heater connector and thermocouple positive pin.
1 Terminal is Blue - Blue is the other heater connector (also connected to the TIP) and the negative Thermocouple pin.

I use the 2 green terminals to connect to PE with a 1 MOhm resistor. One of the terminals is used to detect if the iron is connected or not. The standby mechanism is also used in a similar way.

An OPAMP with a gain of 221 is used to get voltages below 1V - connected to an ADC input of a Cortex M0 controller with 1.25V reference voltage.

I also decided to use DC voltage and a P-Channel FET to heat the thing up. Temperature /voltage relation is already characterized, working today on the PI regulator coefficients. The PI regulator will run at a rate of 50 Hz to be similar to the original thing.

Edit: The connector can be ordered at Farnell - order number1122379

[damianzet]

Hello everybody!

I'm really interested in the JBC nano. Any update on it? I can be the first to build and test it really need it to help me with my work

[Xyphro]

Hi!

As I got a few private messages, here some updates.
The housing is not prettied up yet and not 100% build together.

Anyway, it works like charm.

Quick video:


(yes, my lab table is a mess right now)

Attached the schematic & 2 PCB photos.

Best regards,

Kai

[Ysjoelfir]

How do you get along with a single supply for the thermocouple amplifier? I am working on a JBC soldering station project myself (which also works pretty nice ) but used a dual supply because I just couldn't get the damn thing to work - the offset was huge in relation to the actual thermocouple voltage.

[Xyphro]

Hi Kai (nice name :-)),

I selected the OPAMP carefully and the characterization measurements of the temperature to voltage curve did not show issues.

My testpoints for this curve were:
- room temperature = 0V
- When I put the running iron into water I get 100 degrees (in the video it was just a wet sponge)
- The point, where it begins melting solder (around 190°C)

Cold junction compensation I left out for the reasons given in my inital post + an inaccuracy of maybe even 20°C would really not matter here.

Best regards,

Kai

[SiliconWizard]

Hi,

I'm also considering building a controller for JBC T210 irons (C210 tips). I have one question that seems to pop up regularly without much definite answer, so if you guys have any idea...

The original JBC controller seem to drive the heater from 24V AC (or 23.5V). Driving it from 24V DC with PWM seems much simpler overall. Is there a definite reason why we should drive the heater with AC (such as premature corrosion??) rather than DC? What do you guys think?

Then, in case driving it with a balanced voltage is really to be preferred, does it seem possible to still use a DC power supply and use a H-bridge?

Thanks!

[ZomBiE80]

https://create.arduino.cc/projecthub/sfrwmaker/soldering-iron-controller-for-hakko-907-v-2-fc75d7

[Ysjoelfir]

Heating with DC lets the tip degrade faster (in theory, I don't have numbers how much) because of electromigration. So heating with AC is prefered. As I wrote, I don't know how much faster this really is. I have built a prototype of a benchtop version JBC controller for T245/T210 which works with AC (actually with 30V AC because I didn't have an appropriate transformer... Damn that thing heats fast!) and a small, portable Version (just 25x25x50mm + external PSU) which runs on an 24V DC Notebook powerbrick. Both work very well. I would expect the idea of using an H-bridge could be an apropriate way to compensate for electromigration. But is it really necessary, meaning, is the result worth the not insignificantly greater effort?

[SiliconWizard]

Thanks!

I don't have a clue either whether the degradation is significant with DC, and suspect that other factors like tip oxidization especially when using mainly lead-free solder would probably be predominant.

As you just said, the main point in using DC would be to have a simple design that can be powered with external power bricks and/or batteries, which I find handy. On top of that, since the heater and the thermocouple share a common, as I reckon, that should be a bit easier to get reliable measurements when using PWM, because you can control exactly when it's off.

The H-bridge approach would not necessarily cost a lot more. There are integrated H-bridge controllers that embed the controller, the power transistors and even current limit + current measurement, which would allow some added protection for the tips.

The AC-approach probably costs significantly less overall (and additionally has probably a bit better efficiency), so that makes sense for high-volume production. But for prototyping or a for a low-volume production, that would just be a matter of a few bucks more.

Since you have tried both the DC and AC approach, have you noticed any difference in heating times and recovery?

[Ysjoelfir]

Regarding the costs of the H-Bridge: I thought especially about the temperature sensing, not the heating itself. If I am not overlooking something, that could be potentially difficult.
AC is not necessarily cheaper than DC - with DC you can just use a FET, directly controlled by the µIC. If you want to switch AC with FETs you need an isolated voltage source and two FETs. Using an SCR is possible, but I experienced quite a big loss and quite a lot of heat so I decided to use FETs instead.


I did indeed notice a difference in AC and DC. A note first: I have also an original JBC AD2200 which is the AC reference I refer to. As already mentioned, my DIY version uses a 30V transformer which lets the tip heat up even faster than the original station and recovery is... well, instant? But I am pretty sure the lifetime of the tips will suffer quite extensively.

Comparing the AD2200 with the DC DIY station I noticed that the selfmade station seems to be a bit (but not significantly) faster both in initial heatup time and recovery/regulation. I suspect that this is because I can measure the temperature much faster and more often with DC since the AD2200 switches only at mains zero crossing, so in the worst case it has to "wait" around 10 milliseconds whereas with DC I can decide that I want to measure the temperature right about "now".

[SiliconWizard]

I will think about it in more details, but I don't see at the moment what would make the thermocouple measurement trickier when using a H-bridge. The measurement would take place when the H-bridge is completely off anyway (which is a possible state with most integrated H-bridge controllers). One of the thermocouple connection is shared with one of the heater connnection. It would then either see +Vcc, GND or Hi-Z depending on the state of the bridge. I don't know if shorting the thermocouple (when the Heater + is in the GND state) could degrade it? I would guess not. Anyway, if you can think of specific concerns for the temp sensing that I may be overlooking right now, let me know.

I've found nice H-bridge ICs at Infineon for less than 3€ (by 1). They contain fault detection which is handy and would cost quite a few additional components if done just with discrete parts.

The main concern I'm having is with EMI. Direct PWM with relatively high currents, balanced or not, can cause bad EMI issues. And a soldering tip can make a nice antenna. That may be one of the reasons why it's often not used, or just on amateur gear mostly. The nature of the heater elements may naturally reduce EMI but I'm not sure about that. This would at least be a concern to be adressed when considering doing this on commercial products IMO.

As for cost, what I meant is that if you take the overal BOM into account, the DC only approach may cost more if done properly (on commercial products). The AC approach basically just needs a transformer, an SCR and ideally an optocoupler (and then some low-power rectification and regulation for the logic part). The SCR approach seems to be quite common in a lot of commercial soldering stations.
OTOH, a decent, approved DC power adapter in the order of 100W+ may itself cost more than this in high production volumes. Just a thought.

[SiliconWizard]

Just a quick update. I've worked on this a little bit. And yes we were overlooking something obvious, and it's not with the temperature sensing but with the heating part!

Since the thermocouple and heater are in series in JBC tips, and the tip shell is itself connected to this chain, you can't ground the tip shell while imposing any voltage other than 0V on one of the connections of the heater, which defeats the possibility of using a h-bridge scheme to drive it.

So basically, if we want to drive the heater with an average DC voltage of 0, we have to keep the driver isolated from the rest of the circuit, so that it's floating relative to the system ground. This is what is achieved at a relatively low cost by using a separate secondary of the main transformer and an optocoupler. Doing this with a single supply of 24V DC would require to use an isolated DC/DC converter and isolate a few digital signals. Now that's beginning to add complexity and significant cost.

From what I gathered looking at the UniSolder (a quite popular soldering controller) schematics, it actually seems to use either DC or rectified AC, so the heater doesn't seem to be driven with DC-balanced voltage, but instead, either DC or rectified AC. So it doesn't solve the potential electromigration issue, unless I've missed something.

As for the thermocouple conditioning, I'm using an AD8223 for signal amplification, with a reference voltage of 1.2V to keep it in its operating range for input signals down to ground and even a bit lower. Works well with a single supply.

[C]

Think you are missing some things.

For JVC you have three contacts on the plug in tip.
Between tip and controller you have wire which has resistance.
So at a distance you will have an AC signal on temperature reading.
So a whole bunch of resistances that change with current.

If you use the AC to your advantage, you could measure temp at any time.
You could do this by having the equal of a second connected tip, A reference iron.
If you think about this, it the tip wire is at ground at the controller, then a properly adjusted pot will create a matching AC like the heater power.
The pot is adjusted such that the temp value does not change based on the AC heater current.
Your thermocouple amp does not see a large AC input any more because the pot adjustment removes it.

Note that the pot must be adjusted by control circuit as the resistances will change.

[dymbo]

Think you are missing some things.

For JVC you have three contacts on the plug in tip.

Biasing on wrong assumption leads to big mistakes.
First please search for real photos of C105 series tips discussed here. Those only have two terminals like Hakko T-series

[C]

Think you are missing some things.

For JVC you have three contacts on the plug in tip.

Biasing on wrong assumption leads to big mistakes.
First please search for real photos of C105 series tips discussed here. Those only have two terminals like Hakko T-series

With just a little thinking you might see that with idea you can keep the thermocouple amp happy and ready to read value. No time delays coming out of saturation with two connections.

[dymbo]

Think you are missing some things.

For JVC you have three contacts on the plug in tip.

Biasing on wrong assumption leads to big mistakes.
First please search for real photos of C105 series tips discussed here. Those only have two terminals like Hakko T-series

With just a little thinking you might see that with idea you can keep the thermocouple amp happy and ready to read value.

Please expand. Mean, I got the Idea of filtering out the AC so the AMP to hear thermocouple only voltage. Just didn't get "the whole bunch of resistances", pot adjustment and other little details. E.g., thermocouple T isn't read by resistance, but by the voltage... Also, the AC is about to introduce much of a noise that's unlikely to get easily filtered.

[C]

If you think on the total problem.
It takes time for heat in the heater to get to tip.
The greater the differential between heater & tip the faster the change.
To know heat energy you need to know watts.
When combined with temp sensor you have more facts for control.

You can then compute the problem and see the response from the temp sensor.
The feedback can now compute how big the mass the tip is
touching and respond faster. 
So with the facts a processor can do better control.
So when you pick up the iron you get a response curve that will change when tip is not in air.

Above is what you want.
Thermocouple amp is amplifying a small voltage & a big voltage puts output in the rail talking time to recover.

You have a tip with two connections.
From tip to control box you have wires with resistance.

To get watts you need a current sense resistor. Only place to connect is non-tip ground.
The power end of current sense resistor is the spot to connect the virtual iron which is nothing more then a resistor divider that gets fancy.
With larger value resistor in parallel to current sense you get a low current version that changes same as the connection to the handle and back to control.
Proper adjustment of tap gets voltage difference between two inputs to Thermocouple amp in range.
Fine adjustment removes wire resistance.


 

[SiliconWizard]

The discussion is kind of drifting towards thermocouple measurement, which is not the issue I was talking about.
There may be schemes for thermocouple measurement which can reduce or avoid having to shutdown the heater and wait for a delay (when dealing with PWM) or wait for zero-crossing (when dealing with AC drive). But that was not my concern here. This waiting time doesn't bother me actually, since I'm controlling the whole cycle with PWM. The only drawback it has is that we can't have 100% duty cycle. I don't mind. I'm aiming at C210 and maybe C245 tips, and I'll get more than enough max power even with the reduced max duty cycle.

The issue is with the tip grounding.

If you ground the tip for ESD protection, as is done in original JBC stations, I can't figure out how we could drive the heater with a H-bridge, unless it's isolated from the rest of the circuit. It's that simple.
Of course if the tip is not grounded, this is no problem - but I wouldn't feel comfortable with this. I want ESD protection.

[C]

SiliconWizard

For the three connection tips this is easy a floating power supply.
For both you build circuit that keeps Thermocouple amp happy then you have no problems.

[SiliconWizard]

Well - when using a DC power supply, typically a "power brick", the solution would be not to connect the outter shell of the tip to the internal ground but just to an external earth connection through a 1 Meg resistor for instance. To avoid issues, the DC power supply would have to have no internal path to earth. A lot of high-power bricks actually have their ground (-) connected to earth and have a mains plug with earth. So that would be a problem. Completely isolated power bricks do exist but they are pretty expensive.

So really, the H-bridge approach seemed interesting but it turns out to be a lot of trouble, especially if we want to use external DC power bricks.

Can anyone who worked with the UniSolder design confirm what I understood of it, that it actually can't drive heaters with a balanced voltage and thus can't avoid electromigration (if that is ever a real issue)?

[C]

First think about PWM.
Great at creating noise.

For a three connection tip, could be some good reasons not to use 50/60 cycle AC, but you could still use AC with a power brick. Higher frequency gets you smaller lighter transformer.
Could be some vantage for two connection tip still.

The important thing is to keep the Thermocouple amp from being effected by power state. Then A two connection tip has a limit of getting good temp reading after some time with out power applied. The less the effect the quicker you can get a reading which leads to part of better control.
The important fact is that things change based on temp & current.
If you collect good facts then micro could adj the circuit as needed to keep Thermocouple amp happy.

To get fast control your micro needs to learn how the tip responds, Each tip will be different.
For example to get from room temp to soldering temp could be X seconds of power then temp slowly gets to tip at time Y with little overshoot. To gain some facts, you might break this up into more power shots, but need to remember that a temp reading is not final when doing this.
With out that knowledge, I think you will find it will take longer using normal control loop.
Most diy designs I have seen gain no knowledge of how much mass the tip is in contact with and just try to control with temp.
With out mass in control loop you have bigger swings and/or slower response.

So stop thinking how to power and think about all the information you could collect and keeping Thermocouple amp happy. This gives best control loop to control power.
But better control costs in getting better input facts.
Some temp controls add a heat sense to current sense resistor.
A lot of electric range burners do this for control.

So a great iron has many facts/sensors in it's control loop.

Start with a lower voltage to check your circuit and verify proper operation. Use your micro for more then a dumb temp control.

Think you will find that you will have a better iron if you can use a higher wattage power source.
JVC gets a lot of advantage from that high wattage source of power but control becomes more critical.

ESD protection works with 1 meg due to isolation.
With grounded power, you need to try to keep tip at ground.
With high power and wire to handle you will still have a change at the tip.

[dymbo]

Well, I didn't get your idea first.
Actually, I'm about to build such a state machine to watch for thermal system response and advance the heating power based on the times it gets to heat up & cool down. As for the AC, I thought about building either the AC PWM, or full PWM SMPS with filtered AC sine output, like those used for Vector [motor] Control or Field Oriented Control with same state machines watching system's thermal dynamics.
I agree there's much room to predict such a system states. Also, there's the heater resistance T drift which is possible to get measured and serve as a second thermal sensor (PTC).
But first that sounded to me like an idea to filter out the AC to read thermocouple voltage remainder.
But the very first is that I must wait for about 1-2 months before I get the micro tweezers and the very tips! 

[C]

With temp change a thermocouple is a varying DC voltage.

Thinking on two connection tip.
That has to effect the circuit. You should see a DC offset in the AC. The problem is that it's a small signal and needs to be made large to get a reading.
So if you have one path that has a thermocouple & a second path that does not have a thermocouple and you power both paths with the same signal ( the power ) you should be able to see a difference.
You have wires in path that change but should effect both half's or AC the same.
You have the heater resistance that should change based on heater temperature but again should effect both half's of AC the same.
If you put a current sense resistor in both paths and measure the difference you should see the voltage of the thermocouple voltage. You would be building a Wheatstone bridge.
https://en.wikipedia.org/wiki/Wheatstone_bridge
If Rx = cable to handle & tip. Then with proper adjustment of R2
you should get a AC balance with  thermocouple effect showing.

Sensing the heat of current sense resistor should give an idea of heater temp.

By taking a lot of samples, you should get a lot of information.
Rate of thermocouple helps build profile of tip & gives hint of mass tip is in contact with.

Would not be that hard to build some test plots or graphs to see what you can get from data.
Just need a few differential input ADC's that sample at same time to remove time errors.

Starting to wonder if they could be using some audio ADC's & DAC in a circuit.

[dymbo]

You would be building a Wheatstone bridge.
https://en.wikipedia.org/wiki/Wheatstone_bridge
If Rx = cable to handle & tip. Then with proper adjustment of R2
you should get a AC balance with  thermocouple effect showing.

That's what I was thinking even before your post, but as a secondary option to get more effecient control loop.
Indeed we must measure the power applied to the heater to diffirentiate the response.

Sensing the heat of current sense resistor should give an idea of heater temp.

I believe, it's kinda overshooting approach. First, we loose energy on such a resistor. Indeed it's a low value chained with the handle circuit to get any reasonable to measure T change on it.
On the other hand, the heater resistance has a drift over T range which can be measured as long as we measure the power. Just need some "calibration" stage on the tip change. And no power loss, just a high value R in parallel to the handle circuit.

Rate of thermocouple helps build profile of tip & gives hint of mass tip is in contact with.
Would not be that hard to build some test plots or graphs to see what you can get from data.
Just need a few differential input ADC's that sample at same time to remove time errors.

Yep, it's about just a simple maths. The state watchers should be calculating correction factors to the main PWM cycle.

Starting to wonder if they could be using some audio ADC's & DAC in a circuit.

The best way to find out is to tear down the real JBC nano station. Unfortunately, we don't have one to reverse-engeneer.

BUT! We could be building even better, should they haven't realized neither of the ideas. Honestly, I wonder if they did. More likely they would have built it around fancy algorythms.
Have you ever seen the Hakko T-series oscillograms? Not even a hint on a precise PWM control, it just skips N half-waves from a transformer!
To me it looks ridiculous nowadays, moreover considering the price 

[C]

Sensing the heat of current sense resistor should give an idea of heater temp.

I believe, it's kinda overshooting approach. First, we loose energy on such a resistor. Indeed it's a low value chained with the handle circuit to get any reasonable to measure T change on it.
On the other hand, the heater resistance has a drift over T range which can be measured as long as we measure the power. Just need some "calibration" stage on the tip change. And no power loss, just a high value R in parallel to the handle circuit.

one path for Wheatstone bridge is the current resistor and handle/tip. This resistor produces the most heat and will be apx of heater temp.

The TS100 soldering iron could supply a lot of the firmware.

The ridiculous is the prices even for the handle.

A great iron is all in the huge power and fast control compared to lesser irons. Making the most of all the data/information that can be collected and using it in control.

In addition to Wheatstone bridge, the AC is suppling a dither signal. Might gain even more data with a low power dither.
having three states for power. This might help with time from heater to tip.

Then it might help to have control loop make the tip oscillate about set temp some. Could help sense tip touching mass, but would be a very slow.
 

[SiliconWizard]

Just found this oldish thread: https://www.eevblog.com/forum/projects/electromigration-in-soldering-iron-heaters/

There is still no definite answer, but as I suspected, AC driving may be mostly used for cost reasons. Electromigration in soldering tips heaters probably has little chance of getting significant during the tip's lifetime.

So for now my controller won't drive the heaters with a 0V DC offset. Doing this with PWM DC control would be too expensive as it would need isolation as I explained above. I will still use the H-bridge to be able to use both T210 and T245 irons with the same connector (connections to the heater are reversed as explained here: http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=7218&p=61175#p61175 )

[hexpope]

Hi all, I am also in the process of designing a controller for the JBC line of products.  I think I will be using DC for the initial tests.  I noticed a lot of you guys like to use OPAMPS given the that the TC of the iron is in the uV range on the JBC.  Has anyone tried using the TI ADS1115 at all in their tests and leaving out the OPMAP from their design with good results? Looking at the specifications its a fairly decent ADC

[SiliconWizard]

I noticed a lot of you guys like to use OPAMPS given the that the TC of the iron is in the uV range on the JBC.  Has anyone tried using the TI ADS1115 at all in their tests and leaving out the OPMAP from their design with good results? Looking at the specifications its a fairly decent ADC

I'm using an ADS1115 in my design, but with an AD8223 as a front-end, with a gain of 25.

An ADS1115 alone will give you a couple problems. When used single-ended with very low voltage input signals, the SNR will probably not be that great. And yes, you will have to use it single ended, because the TC in JBC cartridges is in series and one of its ends will have a low-impedance path to ground.

Also, if you plan on using C210 cartridges, the TC has a very low temperature coefficient of a little less than 10 µV/°C. Given than the smallest full-scale range of the ADS1115 is +/-256 mV, and that you get half of that when used single-ended, you'll get a theoretical LSB of ~7.8 µV. Thus in a real-world environment, I would expect an effective resolution of several °C, which exceeds what I would like to deal with. Then again, for a simple controller, you may find this appropriate. Feel free to experiment and report back. There are ADS1115 breakout boards, you could prototype this in a couple of hours and see what you get.

I am currently in the process of finalizing my prototype and will post my results once it's done, probably in a new thread.

[C]

An ADS1115 alone will give you a couple problems. When used single-ended with very low voltage input signals, the SNR will probably not be that great. And yes, you will have to use it single ended, because the TC in JBC cartridges is in series and one of its ends will have a low-impedance path to ground.

You do not have to use single ended mode.
Smart would be to use differential.
With differential input this gives an input that can counter effects of power on/ power off.

[hexpope]

Thanks for the feedback regarding the ADS and also the type of OPAMP you are using.  I have few "Auto zero with little, to no drift" Opamp's here which are the dual and single rails from Microchip MCP6V01 and the MCP6V02.  I think these will suffice for tests for now. I am going to order the ADS along with the new ESP32 WROVER-I as I am testing with a WROOM atm on a bread board for other features with a Nextion.  I am also wondering if the new silicone version of the WROVER has sorted out their not so great internal ADC

I am also designing the power supply based on a LM5117 for this station with a 500+VA toroid

I am currently in the process of finalizing my prototype and will post my results once it's done, probably in a new thread.

Please let me know when you have your thread up and running. It would be a great help for myself to look at.  Which method are you driving your heater/s with ? PID ?

regards

[SiliconWizard]

with a 500+VA toroid

That sounds like A LOT OF POWER. I don't think you need that. What kind of tips are you targetting?

Which method are you driving your heater/s with ? PID ?

As you have seen above, I'm driving the heater with an H-bridge controller (TLE9201SG). Initially, I wanted to drive the heater with 0V DC offset, and the H-bridge was meant for that, but as I explained earlier, it can't be done without isolation and that would be costly. So I'm using it to allow the station to accept both T210 and T245 with just one connector (original JBC connector, Hirose RPC1). You could take a look (if you haven't already) at the UniSolder project (which isn't mine) to get more information and figure out why this would be necessary.

I won't be using a conventional PID, I'm trying something else. Something based on the "take-back-half" algorithm that I have improved to get better transients. Haven't tested it on real hardware yet (I will as soon as the prototype is ready for that), but I've simulated it extensively (granted, with a much simplified heating model) and compared it to a PID. I get much better regulation and it's dead easy to tune, whereas correctly tuning a PID can take a while. We'll see if it behaves as well in real life.

[hexpope]

The reason I am using the 500+VA toroid is that I would like to have the tweezers & C210 running & C245 simultaneously.  This is why I opted for a 500+VA plus I will have room for different revisions of my project if I decide to upgrade in the future. The station will more than likely be a 3 port.

Yes, I should look at the Sparky's thread thoroughly. I have glanced through it now and then . It's completely massive so it would have to be during a coffee time when I am not tired. When I was having a quick look at it, I did notice a Russian member posting these links on Taobao in which I will probably order 3 stands and 1 C245 handle and a few tips for it, as they are very cheap. The other two stands I will modify to take the Micro Tweezers and C210 pencil which I will order from Batronix.



Check these out, I will order through superbuy agent which in turn will turn out cheaper than the 160 euros per stand from JBC

https://item.taobao.com/item.htm?id=545728711654

and the tips

https://item.taobao.com/item.htm?id=36360310685

Have you seen this on Github ?

https://github.com/timothyjager/JBC-Soldering-Controller

[jry2]

hexpope, How do you plan to limit current going through C210 and C245 tips?

Btw, I have another JBC driver prototype working with C210 and C245 tips: http://dangerousprototypes.com/forum/viewtopic.php?p=64377#p64377

Thank you for Taobao links, interesting.

[hexpope]

Thanks for your link to your project JRY2. I must have a read over it.  I think I might have spotted it last year at some stage.

As in regarding the current limiting for the different types of pencils and tweezers, The LM317 looks interesting when configured for current regulation, or maybe a transistor current limiting method.

I am sure it can be done in software also as there will be three ports on the station in which will be only for the specified tools.  I am not much of a software coder and I am no expert in electronics either! I will probably need help in this project now and then.

[SiliconWizard]

The reason I am using the 500+VA toroid is that I would like to have the tweezers & C210 running & C245 simultaneously.  This is why I opted for a 500+VA plus I will have room for different revisions of my project if I decide to upgrade in the future. The station will more than likely be a 3 port.

OK then. Sounds like a monster.
Given the very short heating time of JBC tips, I'm not sure it adds a lot of value to be able to have 3 of them run simultaneously, unless of course you plan on having 3 people working with the same station at the same time. Granted it will save you the time of plugging/unplugging them (but in the scenario where they are not used simultaneously, you don't need that much power).
But why not.

Yes, I should look at the Sparky's thread thoroughly. I have glanced through it now and then . It's completely massive so it would have to be during a coffee time when I am not tired.

You should, there's a lot of information on the different kinds of tips and the associated hurdles. So you don't have to waste more time experimenting.

Are the tips from Taobao genuine or just fake low-quality ones? I'm a bit wary. Got my tips (genuine) for around 20€ each.

Have you seen this on Github ?

https://github.com/timothyjager/JBC-Soldering-Controller

Yes (unfortunately the schematics are in Altium format only, would have liked PDF, unless I missed them). I have seen a lot of other similar projects as well.
They are all more or less the same. They either use AC drive with a MOSFET driver optocoupler + 2 MOSFETs or DC drive with some kind of high-side switch (PMOS or integrated driver).

As for current limiting, with so much available power, this is not an option. If you don't do this, you're going to fry your tips. Especially the C210 ones which are tiny and I think are rated for 50W peak and 20W continuous.

[jry2]

As for current limiting, with so much available power, this is not an option. If you don't do this, you're going to fry your tips. Especially the C210 ones which are tiny and I think are rated for 50W peak and 20W continuous.

Exactly.

Also if you are looking for JBC microtweezers driver, look at mentioned thread http://dangerousprototypes.com/forum/viewtopic.php?p=57058#p57058 - there are some gotchas.

[hexpope]

@SiliconWizard

There is a PDF of a schematic in the folder \JBC-Soldering-Controller-master\Hardware called JBC-Soldering-Controller_SCH_[No Variations]

I was well aware of the C210 and the tweezers to have current limiting capabilities as I have read from other people they fried them during tests and given the toroidal power I am using. If I am using DC to run the tip/s I should be able to limit the current with the LM317 in current regulation mode ?

The tips from the Chinese are not genuine tips but there was a thread here on the forums where people have the original tips and then tried out the Chinese versions with excellent results. I don't have the thread to hand, but will link it when I am back later.


@jry2

Thanks for the link again to a certain post in the big thread.

You seem to have / had the same idea as I want to basically build.  I have built a Weller tweezer and RT pencil driver designed which the uC controls the two tips independently and regulates them. It's a very good controller. I would probably would have built from his design a bigger controller but Wellers microtweezers isn't great for microsoldering on high destiny iphone/ipad boards etc... and their smallest tip is 0.2mm and the way they designed their tweezers isn't the best for getting in around certain parts compared.  Here's a demonstration of what I am on about ...

https://youtu.be/syjEbtffkag?t=2m44s

Weller driver that I have built from

http://kair.us/projects/weller/index.html

[SiliconWizard]

@SiliconWizard

There is a PDF of a schematic in the folder \JBC-Soldering-Controller-master\Hardware called JBC-Soldering-Controller_SCH_[No Variations]

OK - missed it because the whole file name was truncated so I had assumed it to be an Altium file or something. Just took a look, and realized that I've seen this schematic on another web site actually. Didn't remember it was this same guy. So yes, as you can see, he uses an high-side power switch and an ADS1118 for TC measurement. I use an ADS1115, mainly because it's I2C and I have a few I2C ICs in my design, so that was handy. I can use a 48-pin µC (with only 2 IOs left). The 1118 has an integrated temperature sensor, which the 1115 doesn't have. But I use a separate temp sensor (Si7051).

Whether you use a front-end amplifier or not, don't forget to add the protection you've probably seen in several schematics: the series resistor with 2 diodes. Because when the heater is ON, this can see 24V. In this guy's design, the series resistor is only 470 ohm and there are no external diodes. I don't think this is proper protection. The internal pad diodes of the ADS1118 will clamp it to Vcc+Vf at a current of approx 50 mA, which may destroy them in the long run. And I'm not talking about kick-back due to the inductive characteristic of the heaters. Ouch. In most controllers I've seen, a series resistor of 5k to 10k is used followed by two diodes to ground in opposite direction.

If I am using DC to run the tip/s I should be able to limit the current with the LM317 in current regulation mode ?

Yes, or any hardware current limiting option. You could do this in software only, but as I gathered, you may not be confident enough in your software skills to do this safely (and there are always possibilities of bugs).

One thing to consider is that to get the most of those tips, you'd ideally have to implement a current limitation that's different for the short or long-term. Allowed peak power for fast heating is at least twice what is recommended for continuous power delivery.

[hexpope]

I am also using protection on various parts of my schematic in the way you are describing.  I have the ADS1115 ordered for the weekend to play with.  The uC I am using is the ESP32 for testing purposes. I don't know if it will be in the beta design when I get some PCB's from China.

Here is the thread I was talking about earlier regarding the Clone vs the Real deal...

https://www.eevblog.com/forum/reviews/good-jbc-clone/msg1379885/#msg1379885

[SiliconWizard]

OK I see. I would personally not buy this kind of clones. Even buying genuine tips (which are necessarily better than the cloned ones) is, I think, fair to JBC. The tips are fantastic and really are the core of their innovations. The controllers themselves are expensive for what they are and I'm pretty sure this is not even what they are making their money off.

Making our own controllers is not just to cut costs IMO (when you count the parts and time you spent on it, you'll realize you haven't saved any money anyway - surely the opposite). This is all for the challenge, trying to get better temp regulation, adding features that are not in the original, making them smaller, etc. At least this is the way I see it.

[Xyphro]

Hi!

Did not read the last few messages, but I got recently a lot of PMs on getting the source code of my JBCNanoSolder station.

Please get it from here:
https://drive.google.com/drive/folders/1bPjQK-itiDwoskBm1YyCvSkDXdZCBUl1?usp=sharing

Best regards,

Kai

[hexpope]

Hi Kai,

THank you for taking the time to upload this for people.

Best regards

[Iwanushka]

hi,

does anyone know exact part number for the socket for JBC nano tools? all I know its mini Binder 5pin socket.

[hexpope]

hi,

does anyone know exact part number for the socket for JBC nano tools? all I know its mini Binder 5pin socket.

Look on the first page.

[Iwanushka]

hi,

does anyone know exact part number for the socket for JBC nano tools? all I know its mini Binder 5pin socket.

Look on the first page.

All shops find 8pin connector only by that part number

[FransW]

Any packages available for self-assembly?

Thanks, Frans