Announcement

Collapse
No announcement yet.

Handler 175 Wire feed speed fluctuates

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Handler 175 Wire feed speed fluctuates

    My 175 started intermittently welding like crap, Sometimes it lays down a beautiful bead, and other its just starts popping and spattering, and trying to burn back. After covering all the basics for the symptom no bacon sound for me, I decided to take a comprehensive look at it. It's down to this:
    Drive motor
    Control Board
    Fan Motor 24AC to Control board
    My 175 is 20 years old, Ser #: LA268793, all maintenance is up to date.
    Fluke 88 DVM used for measurements
    .035 ER70S6
    C25 @ 20 cfm
    New Liner installed last week

    Here's what I have from troubleshooting
    RC1 Pins 1& 2, 31vac. is this too high?
    RC2 & 3, Motor feed voltage, when I do the tension test with the wire hitting a flat surface, motor slows down, @ speed 75 voltage is from 11VDc down to 7VDC, So no wonder it welds like crap.

    What else should I check to nail it down before decideing how to repair it? Right now I lean towards the control board, and possibly the fan with it sending 31vac to the board. If its repair the Control board, I can do that if I know what components need replacing.

    Thoughts from the experts? More checks I need to do?

  • #2
    Went through the machine yesterday and checked all the resistance and voltage test points, all good. Last thing I did was compare the torque output of the feed motor hooked up to a car battery to the Control board output. Its fine on the battery, maintains the speed when I let it curl wire against a surface, bogs done when i do the same thing via the Control board. I ordered a few Q1 2N6388's from Digikey to fix it.. At $.85 Ea, might as well have a couple spares on hand ...

    Comment

    Working...
    X