Page 2 of 3 FirstFirst 123 LastLast
Results 16 to 30 of 39
  1. #16
    Join Date
    Jun 2010
    Location
    Canberra
    Posts
    1,322

    Default

    Quote Originally Posted by neevo View Post
    Thank you very much!

    I will have to open up the machine again and check the 7 pin wiring. Your wiring makes sense to me and yet I only have 4 wires going to the socket. It looks like the wiper is missing which would be essential for any potentiometer regulation.

    Can you see inside the machine at all? Do you have 2 pairs of wires coming from the plug?
    Won't be near the machine again for a while, so can't really say.

    Just noticed, post #5 in this thread by jackaroo has a schematic that matches what I measured.

  2. #17
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Quote Originally Posted by RustyArc View Post
    Won't be near the machine again for a while, so can't really say.

    Just noticed, post #5 in this thread by jackaroo has a schematic that matches what I measured.
    I will pop the cover and recheck. Definitely sounds like the error is on my end. Thanks bud!

  3. #18
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Odd; I pulled the cover and there are definitely only 2 wires for the switch and 2 wires for the amperage control.

    Looking hard at the amperage control it looks like it’s a factory thing too as I cannot see any solder on the back of the 7 pin plug and the wires to the board are also tidy.

    Looking online many people quote you cannot add a pedal to the Unimig DC 200 Razor for some reason but when I look in the manual it clearly states you can.

    Don’t want to be playing around with it either in case I fry something.

    It looks like my best bet is to buy a torch with amperage control built in and see how that works.

    Pics show:

    Rear of connector
    3 pin connector (this is for red/green) appears one of the pins is unused
    2 pin connector on top board (red/black)
    Closer pic of unused and unsoldered pins

  4. #19
    Join Date
    May 2011
    Location
    Murray Bridge S Aust.
    Age
    71
    Posts
    5,942

    Default

    Does your manual give a wiring diagram????
    Kryn
    To grow old is mandatory, growing up is optional.

  5. #20
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Quote Originally Posted by KBs PensNmore View Post
    Does your manual give a wiring diagram????
    Kryn
    Unfortunately not. Just a notes page at the back.

    I might grab a torch with adjustable amperage on it and see if I can reverse engineer it from that (hopefully it works).

  6. #21
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    If there's only 2 wires on the amperage control then good chance it's just the wiper and one other on the pot.

    Steve

  7. #22
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Quote Originally Posted by OxxAndBert View Post
    If there's only 2 wires on the amperage control then good chance it's just the wiper and one other on the pot.

    Steve
    I’ll grab a cheap 10k potentiometer and have a go to see if I can get that to work.

    Seems rediculous to charge $250 for a pedal with a 10k pot and a few wires!

  8. #23
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    I have the switch worked out. Managed to grab a foot pedal momentary switch from Jaycar and made a simple foot switch. Connected via pins 1/2 and it works flawlessly.

    Wow do I love this TIG machine. It’s in another league welding with HF start, having pre/post flow and pre/post amperage.I also had a go with pulse which is also super cool to use. Can’t wait to get more time on it and improve my welding.

    To progress the proper foot pedal I’ve bought a torch with amperage control. Also means I have a 26 torch here when I need it as I’m currently using a 17 torch. Having the amperage control with the torch will let me see if it works with the machine, and if it does I can hopefully test the torch to see how it’s working. I’ve also purchased a 10k potentiometer to do some testing if required.

  9. #24
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    I don't have a pedal so if I need to I use the downslope as a form of current control.
    Release the torch trigger and the current starts to drop. Press it again and current comes back up to full. You can get pretty reasonable control by how quick you cycle and how much you let the current decay.

    Steve

  10. #25
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Quote Originally Posted by OxxAndBert View Post
    I don't have a pedal so if I need to I use the downslope as a form of current control.
    Release the torch trigger and the current starts to drop. Press it again and current comes back up to full. You can get pretty reasonable control by how quick you cycle and how much you let the current decay.

    Steve
    yeah I was using that yesterday. Pin holes have vanished vs scratch finishing. Nice 2-3 second up/down slope with low 20 amps was giving me amazing control.

    I can only imagine what it’s like with a proper pedal

  11. #26
    Join Date
    Aug 2006
    Location
    Melbourne
    Posts
    1,105

    Default

    Quote Originally Posted by neevo View Post
    I’ll grab a cheap 10k potentiometer and have a go to see if I can get that to work.

    Seems rediculous to charge $250 for a pedal with a 10k pot and a few wires!
    You can pick them up a lot cheaper than that, might just need to change the wiring/plug to suit your machine.

    https://www.ebay.com.au/itm/TIG-Weld...frcectupt=true

  12. #27
    Join Date
    Dec 2018
    Location
    NSW
    Posts
    586

    Default

    I've got a pedal with a 5 pin amphenol plug, and a min/max pot on the side (effectively controlling the starting amperage and max pedal depression amperage).
    Will upload a ruff'n'dirty wiring diagram of it when I can. Maybe even get some electrical help on what's actually going on with it.

  13. #28
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    666

    Default

    Quote Originally Posted by Com_VC View Post
    You can pick them up a lot cheaper than that, might just need to change the wiring/plug to suit your machine.

    https://www.ebay.com.au/itm/TIG-Weld...frcectupt=true
    Ive bought one of those already in the hope I can rewire it. Just need to figure out the 4 pin wiring!

  14. #29
    Join Date
    Dec 2018
    Location
    NSW
    Posts
    586

    Default



    Here's what I've found for a 5-pin foot controller.
    This one is a bit different, as it has 2 pots on the side of the pedal that allow the operator to dial in a minimum 'starting amperage' and a maximum amperage at full pedal travel. I'm deconstructing it as it is not working properly- I think I narrowed it down to a dodgy linear pot.

    Connector is a amphenol 5 pin. FWIW a quarter turn engagement type.
    Pin layout 1-5:
    1) Yellow/Green tracer - HF start (ignition) switch (NO normally open)
    2) Purple - HF start (ignition) switch (NO normally open)
    3) Orange - goes to pin 2 on the slide pot (the wiper)- this is the pot that is operated as the pedal is depressed.
    4) Black- goes to the 'max amperage adjustment' pot pin 1.
    5) Blue- goes to the 'max amperage adjustment' pot pin 3 (low to max indicates position of pin on the pot relative to the way it is operated in the device). Pin 2 on these 2 adjustment pots are the wiper.

    Question I have- Hoping to check as I'm probably wrong
    1) Would it be low or high return voltage to the machine that indicates a high welding current? Is there any hint in the way this unit above is wired?
    2) I think the way it works is that the black wire from machine pin 4 feeds the max pot (pin1), and the voltage drop at full length of the wiper (max pin 3) is fed into pin 1 of the MIN pot via the red wire. MAX and MIN pot wipers feed voltage to each side of the pedal control slide pot (pin 3 and 1 respectively), with pedal actuation giving a voltage signal to the machine control board (ie an amperage setting) via the ornage wire (machine PIN 3).

  15. #30
    Join Date
    Jun 2010
    Location
    Canberra
    Posts
    1,322

    Default

    I don't quite get what pin 5 connects to?

Page 2 of 3 FirstFirst 123 LastLast

Similar Threads

  1. Poor Mans DRO
    By Oldneweng in forum METALWORK GENERAL
    Replies: 14
    Last Post: 31st Jul 2015, 11:15 PM
  2. Cincinnati pedal power
    By tongleh in forum METALWORK GENERAL
    Replies: 13
    Last Post: 9th Nov 2012, 06:54 AM
  3. Poor man's DRO
    By Big Shed in forum METALWORK GENERAL
    Replies: 14
    Last Post: 7th Aug 2012, 05:01 PM
  4. Left Foot Accel Pedal Update
    By Sterob in forum METALWORK GENERAL
    Replies: 3
    Last Post: 9th Aug 2011, 03:39 PM
  5. Foot pedal question
    By oo7fitzy in forum WELDING
    Replies: 5
    Last Post: 25th Apr 2010, 10:46 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •