Low Cost PCB's Low Cost Components

Author Topic: T12 Soldering Iron Clone Kit  (Read 328 times)

0 Members and 1 Guest are viewing this topic.

Offline don.r

  • Frequent Contributor
  • **
  • Posts: 500
  • Country: ca
T12 Soldering Iron Clone Kit
« on: September 13, 2017, 01:30:58 PM »
Just received my AliExpress KSGER T12 soldering iron clone kit. Has anyone else built this kit? I may post some pictures up if there is interest. I noticed already that the PE connection has no Y caps to N or L and that it basically stops at the PSU input (case is plastic). The PE connection on the iron is just NC (although I haven't confirmed with continuity yet, it looks most likely that it is not connected).
« Last Edit: September 13, 2017, 09:59:11 PM by don.r »
Shippers: for the love of Pete and all that is holy, STOP USING UPS INTERNATIONAL!
 

Online pigrew

  • Regular Contributor
  • *
  • Posts: 205
  • Country: us
Re: T12 Soldering Iron Clone Kit
« Reply #1 on: September 14, 2017, 03:23:50 AM »
I have a similar unit (pre-assembled). I just verified that it doesn't have a good ground connection. They tried at grounding the aluminum case, but paint on the case prevented an electrical connection.

I'll edit this post later and add photos of my unit.

Don.l, perhaps you could post photos of your kit?

EDIT: Photos added of pre-assembled kit (with modifications: Extra ground wire to the iron connector's shell, and ground off the coating from the case in order to allow electrical contact)
« Last Edit: September 14, 2017, 09:05:39 AM by pigrew »
 

Offline don.r

  • Frequent Contributor
  • **
  • Posts: 500
  • Country: ca
Re: T12 Soldering Iron Clone Kit
« Reply #2 on: September 14, 2017, 03:38:02 AM »
PSU shows no Y caps on inputs and ground connection ends at input where its connected to the plastic case. Front panel board has a ground connection going to the tip but is unconnected at the board.  ::)

Shippers: for the love of Pete and all that is holy, STOP USING UPS INTERNATIONAL!
 

Online pigrew

  • Regular Contributor
  • *
  • Posts: 205
  • Country: us
Re: T12 Soldering Iron Clone Kit
« Reply #3 on: September 14, 2017, 09:04:57 AM »
I added photos to my previous post. My board is a "F Wxk T12-D". It's correct that there is only an X cap and no Y caps. The power-board GND terminal isn't connected. There's an extra wire going from the power-input's GND to the controller PCB's COM. Through that connection, the tip is earthed. I added an extra wire to ground the shell of the connector. The unit has a sheet of plastic insulator at the top of the case (prevents shorts if the power supply becomes loose in the unit?).

The COM/GND connection on the controller PCB is just a solder-blob. There were not enough pads for all of the COM wires so they just solder-blobed it together. Even still, I measure less than 1 ohm (approx 0.95?) from the end of my power cord to the soldering iron tip.

My unit has just a basic power-connector on the back, though I've seen photos of a "T12-A" model with an integrated power-inlet that has a fuse.

Also, the ring-connector at the back of the unit was soldered together (I think that it's supposed to be crimped?). There was so much paint/annodization that there was no contact to the aluminum case. I ground off the coating so that my case now has a good ground connection.

Overall, the soldering iron works well enough, though the OLED display is quite dim through the plastic front-panel. I may 3D-print a new front-cover with a simple cutout for the display.
« Last Edit: September 14, 2017, 09:39:09 AM by pigrew »
 

Offline stj

  • Super Contributor
  • ***
  • Posts: 1159
  • Country: gb
Re: T12 Soldering Iron Clone Kit
« Reply #4 on: September 14, 2017, 09:46:02 AM »
unless it uses a 3core cable with earth on it, you dont want Y caps because it will make your iron live at 50% of line voltage!
 

Online pigrew

  • Regular Contributor
  • *
  • Posts: 205
  • Country: us
Re: T12 Soldering Iron Clone Kit
« Reply #5 on: September 14, 2017, 09:54:09 AM »
unless it uses a 3core cable with earth on it, you dont want Y caps because it will make your iron live at 50% of line voltage!

The unit comes with a 3-conductor power port (IEC C6 Mickey-Mouse type). Since I got mine on Taobao, it came with a Chinese-style plug.

Perhaps they assumed that the grounds would not be wired properly, so they didn't want to provide the Y capacitor? However, I would imagine that the parasitic capacitance in the transformer may create the same effect to some extent.

The power-supply does have a position to install the Y-capacitors, they just didn't load them. Though, they share a pad with the fuse, so I'm not sure that both a fuse and pair of Y-caps could be installed simultaneously.
« Last Edit: September 14, 2017, 09:57:01 AM by pigrew »
 

Offline don.r

  • Frequent Contributor
  • **
  • Posts: 500
  • Country: ca
Re: T12 Soldering Iron Clone Kit
« Reply #6 on: September 14, 2017, 10:40:28 AM »
I just installed a pair of Y caps under the board. Just to be clear, there is already an existing Y cap going from secondary negative to primary neutral. I really like the PSU actually. Lots of good clearances, spark gaps on the board and parts where they need to be (apart from the missing Y caps which is not a big deal) like a dual input choke, an NTC thermistor inrush limiter and an X cap on the input. Lots of filtering including a coil on the output. Ripple seems very low. The proximity of the caps next to the heatsinks isn't the best. My IEC has an integral fuse and switch.

The lack of PE to the iron tip is just stupid. I added a wire from earth on the PSU input to the tip E wire (green wire). The fit and finish on the plastic case is a joke, stick to the metal case for a few dollars more.

Mounting the iron socket to the front panel is proving to be a challenge as they soldered the connector on and its too big to fit through the opening and to take the mounting nut and washer off. At any rate the mounting hole is too small for the socket anyway. Dremel time. The knob is also too tall and when the board is rotary encoder is mounted, the push button no longer works because the knob stops at the face plate. Minor niggles but still irritating.
« Last Edit: September 14, 2017, 10:49:03 AM by don.r »
Shippers: for the love of Pete and all that is holy, STOP USING UPS INTERNATIONAL!
 

Online pigrew

  • Regular Contributor
  • *
  • Posts: 205
  • Country: us
Re: T12 Soldering Iron Clone Kit
« Reply #7 on: September 14, 2017, 10:48:01 AM »
I just installed a pair of Y caps under the board. I really like the PSU actually. Lots of good clearances and parts where they need to be (apart from the missing Y caps which is not a big deal). A dual input choke and an X cap on the input. Lots of filtering including a coil on the output. Ripple seems very low. The proximity of the caps next to the heatsinks isn't the best.

The lack of PE to the iron tip is just stupid. I added a wire from earth on the PSU input to the tip E wire (green wire). The fit and finish on the plastic case is a joke, stick to the metal case for a few dollars more.

Mounting the iron socket to the front panel is proving to be a challenge as they soldered the connector on and its too big to fit through the opening and to take the mounting nut and washer off. At any rate the mounting hole is too small for the socket anyway. Dremel time. The knob is also too tall and when the board is rotary encoder is mounted, the push button no longer works because the knob stops at the face plate. Minor niggles but still irritating.
How do you choose the value of the Y capacitor?

I might not add them since I don't want to deal with digging all the potting compound off of the board. I'll definitely design a new front panel. I have the version without the two LEDs. I think the new "T12-A" boards have the extra power light. I wish the firmware would allow brightness adjustment, but mine doesn't (at least in English; I didn't check the Chinese menus....).
 

Offline don.r

  • Frequent Contributor
  • **
  • Posts: 500
  • Country: ca
Re: T12 Soldering Iron Clone Kit
« Reply #8 on: September 14, 2017, 10:51:07 AM »
Since they are on the inputs before the choke its not too critical and only to suppress noise. I had some 220nf 400V ones kicking about so I used those. They properly need to be after the choke but meh...
« Last Edit: September 14, 2017, 10:54:50 AM by don.r »
Shippers: for the love of Pete and all that is holy, STOP USING UPS INTERNATIONAL!
 

Offline don.r

  • Frequent Contributor
  • **
  • Posts: 500
  • Country: ca
Re: T12 Soldering Iron Clone Kit
« Reply #9 on: September 14, 2017, 01:02:26 PM »
Kit is now all together and works fine. Plastic case has really poor fitting of boards. Had to snip off a corner of the front panel circuit board to make things fit. Bottom line, stick to the metal case. Other than that the iron works great. Heats really quickly. Temp comes in at about 20C below reading but I probably have to run the tip in for a few minutes to get a more accurate reading. Iron goes to sleep (200C) and wakes up with a shake. Its 300C in about 5-10 seconds.

Good:    - PSU
             - Iron itself
             - Price (I paid about US$40 delivered, kit + 4 tips, no power cord)

Bad:      - Tip grounding. Tip earth and negative are connected on the front panel board but with no ground connection to PE, this is pointless. Clearly they designed this with a metal case in mind so that the rotary encoder would ground everything.
             - Case fit/finish and plastic quality.
             - Pre-wiring of pencil socket makes assembly more difficult.
             - Rotary encoder knob too deep.

tl;dr: decent product but get the metal case version.
« Last Edit: September 14, 2017, 01:06:30 PM by don.r »
Shippers: for the love of Pete and all that is holy, STOP USING UPS INTERNATIONAL!
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf