This is in regards to an old Hobart CyberTIG welder that I modified by putting in a new microcontroller that I programmed in BASIC.
So it is basicallly an arbitrary DC power supply, with a few extra relays that control high frequency arc starting and gas valve.
This thing works just fine in constant current mode, letting me stick weld as well as TIG weld.
Note that it has a big inductor that helps with constant current welding.
Now that I am done with CC mode welding, I started exploring MIG welding, which requires constant voltage. Found a LN-25 wirefeed unit on Craigslist.
The issue at hand is that the output of my welder goes through a large inductor that is helpful in CC mode, but counterproductive for wire feed welding. This inductor weighs perhaps 50 lbs. (?)
So, for nice wire feed welding, I would need to bypass it. I see two ways of doing it:
1) Make a simple bypass circuit using a big contactor and big cable (to be turned on when MIG welding is being done).2) Instead of bypassing the inductor, install a capacitor that would "cancel out" the effect of the inductor.
Can that be done at all, is this an insane idea or not? My hope is that it would be done with a smaller "work envelope", utilizing smaller wires and a smallish capacitor, instead of a bulky contactor and big wire, etc.
Any thoughts on bypassing the inductor?
thanks
i