how can I adjust digital display solderin iron

[generator*****]

ic 7107 as dvm

hi friends I want to make this soldering ıron but I don't how to adjust it.language of document about this iron is in Hungary unfortunately I don't know Hungary. can anybody help me


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and this is the original page of this project

www.freeweb.hu/pa-elektronika/forrasztoallmas.htm

 

[Chris56000]

how to adjust soldering iron

Hi!

It would help if the Hungarian chappie had posted the Eagle Design Files as I could then have a go at reworking 'em into English!

However you might like to try the following. You will need a Digital Multimeter with a suitable Temperature Probe of known accuracy capable of withstanding 500 Degrees Celcius.

Connect the built controller (*NOT* the display/measurement PCB) PCB to the 12V a.c. supply *only* and check the +8V, +5V and -5V supplies are *correct* *before you solder the two PCBs together.* This a precautionary measure to prevent damage to the '7107 D.V.M. measurement IC. Correct any errors before proceeding further!

a) On The Display/Measurement PCB, short circuit point "BE" to ground (pin 30 of the '7107, then adjust R2 until the display reads "000".

b) On the Controller PCB, Short circuit points "ELEM-1" and "ELEM-2" then adjust R3 so pin 1 of IC1a (output) is as close to zero volts as you can get it.

c) You will now need to connect the controller to the iron and transformers as follows:-

i) Terminals "ELEM-1" and "ELEM-2" to the iron's thermistor (sensor pins) on its connector socket

ii) Terminals "FUTOZALHO" are connected to the iron's heating element pins on its connection plug

iii) The 24V a.c. supply needs to (ideally) be of about 80VA rating (3.25A) and the 12V a.c. supply about 1A rating.

iv) Set the slider of R10 to to its bottom-end nearest point 'A' and the slider of R11 to its bottom-end (point 'A') then turn the main panel control R12 fully anticlockwise (nearest point 1A). Use your DVM on its AC voltage range to ensure the a.c. voltage across the iron element is as close to zero as possible - if you can't get zero, leave the iron 10 mins to stabilise and after this period of time, measure its tip temperature with your DVM temperature probe.

v) Now readjust R3 so that the display reads the same (in degrees C) figure as indicated on the Digital Multimeter.

vi) Turn R11 & R12 to maximum (ends 'E' & '1E') as shown on the circuit. Allow a further 10 (preferably 15) minutes for the iron temperature to stabilise at its maximum possible setting, then read off the final bit temperature.

vii) Adjust R2 again on the display/measurement PCB so that the display shows the indicated bit temperature.

viii) You will now need to carry out some experimentation with all the settings detailed above until you get the display to "track" as accurately as you can with the DVM/temperature probe). After completing this as best you can, I suggest you
adjust R11 on the Controller PCB to give a maximum possible bit temperature of about 460 Celcius. I can't decipher the Hungarian details of the iron originally used but it seems to be the same as the Weller Electronically Controlled ones!

NB! The 'Magnastat' type irons whigh give a periodic faint click as the switch opens & closes are *not suitable* for this circuit!

d) Control functions:-

Controller PCB:-

R3, IC1a Offset Adjustment/Gain
R11, Set Bit Max Temperature
R12, Main Front Panel Control Bit Temperature Adjustment
R13 Set Bit Min Temperature

Display/Measurement PCB:-

R2 Zero Set

Hungarian, like most non-Cyrillic E. European Languages is tortuous to render into English & I've given it my best shot from the posted Circuit Diagrams! There are also some pictures showing the setting-up on the Original Web Site but it'll probably not be easy to untangle their meaning!

Sorry for the length of the post, I hope its of assistance to you!

Chris Williams

 

[generator*****]

how to connect display in pcb

thank you so much for your help

 

[eem2am]

pcb 7107

just buy an AOYUE soldering iron instead.

pcbsoldering.co.uk

 

[RenatoBR]

how to adjust digital temperature controller

Generator, is this unity for iron solder with thermistor or thermocouple K type?


Renato

 

[Chris56000]

Hi!

This project was probably designed to use an iron of the 12V 30-40W thermistor type!!! (thermocoople irons would show a very low/short-circuit reading across their sensor terminals, thermistor irons would not!!!)

To check measure the resistances across the terminals/plug connectors of the iron you propose to use, the heating element would be 4-6 ohms and the sensor anything up to 20-50k. Apply 12V to the iron's heater element for a few seconds, just enough for you to feel it start to get hot, then measure the sensor resistance - it should be noticeably lower than its "cold" reading and therefore you have a suitable iron for the proposed controller!!!

Fleabay should have plenty of these 12V thermistor-type irons to look at!!!

Unfortunately the original project page has now completely disappeared to be replaced by a useless domain advert., so I've not been able to do any more on it!!!

If anybody took copies of the original piccies from when the site was up and reposts 'em I'll have another go at it when time permits!!!

Chris Williams