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Topic: My HAKKO classic and T12/T15 soldering controller (Read 292834 times) previous topic - next topic

Re: My HAKKO classic and T12/T15 soldering controller

Reply #60
Jbc is a better choice than bk3000lf, but C245 tips are expensive.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #61
welcome back from holidays ;)
@sparkybg: could you tell me if there is any difference in soldering performance between using your controller with T12 tips and original JBC with C245? I saw in your video that JBC heats up much faster, so you can actually set the resting temp to ambient and the tip will heat itself up to the working temperature while positioning the tip for soldering, but on the other hand T12 can have resting temp at around 150 degrees and it will heat up to the working temp in similar time. And as you mentioned - the tips are much cheaper (around €4 vs €20-30 for JBC).

Re: My HAKKO classic and T12/T15 soldering controller

Reply #62
C245 is clearly better. And the quality is much better.

However, everything I can do with C245, I can do with T12 also.

I am using immediate rest temperature of 300 degrees (30 seconda) and deep resting temperature of 200 degrees. T12 heats up in seconds (5-6 maybe) form 200 to 350.

C 245 can be set on 200 immediate and 150 deep, and you will not be able tell the difference if it was on constantly or resting in handle at 150 degrees. It heats up in 1-2 seconds to 350.

But unfortunately I have only 3 C245 tips vs. more than 50 T12 tips. The price of the C245 is around 8-10 times higher than chinese T12.

I've decided to buy 3 C245 tips I am using most of the time, and use T12 for everything else.

C245 is a damn good soldering tip. The handle also is good.

It is like a really good car vs chinese copy of really good car. :)

Re: My HAKKO classic and T12/T15 soldering controller

Reply #63
Does anyone know what the pinout for the FM-2027 is? I would like to try this out and ordered a handle from hakko but I have no idea what connections are what and there are 8 pins on this thing. Found the two I think are the heater because it measure around 9 ohms between them but where would I read the thermocouple from. I assume some of the other pins are for detecting removal of the tip. I read this whole thread but nobody mentions the pinout for this thing. Also if anybody is looking for a connector for the FM-2027 the Digikey part number 361-1267-ND is the matching female connector.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #64
[quote author="mihnen"]Does anyone know what the pinout for the FM-2027 is? I would like to try this out and ordered a handle from hakko but I have no idea what connections are what and there are 8 pins on this thing. Found the two I think are the heater because it measure around 9 ohms between them but where would I read the thermocouple from. I assume some of the other pins are for detecting removal of the tip. I read this whole thread but nobody mentions the pinout for this thing. Also if anybody is looking for a connector for the FM-2027 the Digikey part number 361-1267-ND is the matching female connector.[/quote]

The thermocouple is in series with the heater. The power to the heater is delivered there, end while the heater is off, the thermocouple voltage is measured on the same 2 pins.

There's a third pin, connected to the T12 outer body. This is usually grounded for ESD Safety. Some people leave this pin unvonnected, some connect it to ground using 1-10 megaohms resistor, some connect it directly to ground.

But, I think you will not be able to get a female socket for this plug anyway (it is not a standart DIN plug), so you will have to replace it with something else available at your place. Only 3 pins are needed for T12 tips - ground, + and -. You can measure which one is + using a DMM and a cigarette lighter - when the tip is heated with cigarette lighter,it will start to build a small voltage on the heater pins. The polarity of this voltage is the polarity of the pins.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #65
Thanks for the response, I guess I should have read the original post more closely as it does mention that the thermocouple is in series with the heater. After some testing last night I came to the same conclusion. My question is how are you supposed to measure it when it is setup this way. I am running a AD8495 for reading the thermocouple voltage. If i put a couple of diodes to ground with isolating series resistors I can limit the voltage input to it when the power is applied but it still doesn't read properly unless I completely disconnect the ac lines from it. Should the AD8495 be run without a ground reference, I currently have a 1M to ground on the inverting pin.

The connector from digikey that I mentioned above is an exact match for the hakko plug, I have it already and can confirm this without a doubt.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #66
You must turn power off, wait for the amplifier to settle down (millisecond or two will be enough I think), and then make the measurement.

AD8495 is made for J and K type thermocouples. T12/T15 are not using J or K type thermocouple. How will you compensate for this?

You must put a resistor (10k for example) and then couple of diodes to ground (1n4148 is OK for this), one with cathode to ground, and one with anode to ground, on each amplifier input. This is to avoid overloading of the amplifier because of heater inductance. When you cut the power to the iron, this inductance creates a negative voltage peak on the terminals. Typical inductance of T12/T15 chinese tip is around 150uH, if my LC meter got it right.

I would not use AD8495 for this. It is not made for this. It is a bit slow, and it is made for type K or type J thermocouples. It will be very hard to compensate for this. T12/T15 thermocouple voltage is somewhere around half the voltage of type K or type J thermocouple.

Take a look at the schematics. Use the same amplifier I've used, and compensate for 22-25 degrees room temperature. This is more then enough, and the amplifier is fast enough to be able to settle down for half millisecond.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #67
Makes sense, turns out my problem was that the heater was inductive and I didn't have a snubber on it. I was using the AD8495 only because I made a controller for an old solomon iron I had and was trying to adapt that controller to work with these T12 tips however I guess that isn't going to work and I'll just design a new analog frontend for the thermocouple. Thanks for your help.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #68
[quote author="mihnen"]Makes sense, turns out my problem was that the heater was inductive and I didn't have a snubber on it. I was using the AD8495 only because I made a controller for an old solomon iron I had and was trying to adapt that controller to work with these T12 tips however I guess that isn't going to work and I'll just design a new analog frontend for the thermocouple. Thanks for your help.[/quote]

It will be VERY hard to make a snubber working well on all tips. There's internal inductance, capacitance and so on, and these are not so equal on all the tips.

By the way, I have just tested an original HAKKO T15 (which is T12 for Europe) tip. Electrically there is not any difference between original and chinese clones. There is a little difference in build quality but nothing to justify the 5-7 times higher price.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #69
My project uses the AD8495 and works with T12 tips. Is not yet finished because I had to put on hold the development since came other more important projects I have to finish first. In my previous posts of this topic I refer my approach to this project. You can see if there is anything that can be useful to you.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #70
This is very interesting project. I am looking for an inexpensive soldering station for hobby usage, and this project is just perfect for it.

I really admire the original mains synced approach. However, I was wondering whether it would be anyhow feasable to replace the transformer with a cheap 100W and 24VDC switching mode power supply, and use a MOSFET to switch the heating element current on/off. In this way, the system would be smaller, lighter, it wouldn't have to be synced to mains supply, and using DC would give 30% more power to the heating element. SMPS will produce definitely some high frequency voltage noise, which will affect thermocouple voltage measurement, and needs to be filtered out by the hardware/software. Any comments on these ideas?

Re: My HAKKO classic and T12/T15 soldering controller

Reply #71
I'm using a 24v 4A laptop power supply. In my tests the 50hz noise is harder to filter than some high frequency noise from power sypply.
Using DC does not necessarily mean more power to the heating element because we have to turn off the power to make the readings of tip temperature. Sparkybg use the crossing for zero of the mains wave to do the readings.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #72
[quote author="Kalvin"]This is very interesting project. I am looking for an inexpensive soldering station for hobby usage, and this project is just perfect for it.

I really admire the original mains synced approach. However, I was wondering whether it would be anyhow feasable to replace the transformer with a cheap 100W and 24VDC switching mode power supply, and use a MOSFET to switch the heating element current on/off. In this way, the system would be smaller, lighter, it wouldn't have to be synced to mains supply, and using DC would give 30% more power to the heating element. SMPS will produce definitely some high frequency voltage noise, which will affect thermocouple voltage measurement, and needs to be filtered out by the hardware/software. Any comments on these ideas?[/quote]

The new version of this controller works both with DC or AC voltage form 10 to 30 volts. It is just a matter of software. When AC power is applied, everything works as in this version. When DC is used, I am using 55Hz timer instead of mains supply.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #73
sparkybg, this is just brilliant. I really admire your work on this. Your design is at least as good as the commercial ones, and it is definitely more versatile as it support different soldering handles, has support even for car usage, not to mention that it allows hobby users an access to professional class soldering irons in budget price. Kudos!

I thought about the sensor board. Would a simple and inexpensive inductive proximity senror do the trick of detecting when the soldering iron is in the holder. Something like 46-LJ18A3-8-ZBX or similar (see attached datasheet). The seem to cost around $2.00 each in eBay.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #74
There are endless possibilities for sensing if the iron is in the stand, and of course this sensor is one of them. I made it optical because it was easy to use it in the stands i've got. The controller just wants a logic level signal for this.