Welding Tips and Tricks

I took my precision tig 185 to the shop. The dial would not work raising or lowering amp setings. Shop says "need new PC Board" about $900. dollars.
So my question is can someone recomend a reiable repair service for my board. I have found some online but??
The welder works fine. I really believe it just needs the Potentionmeter replaced. They admit that the "Pot" may be bad but as a Lincoln Dealer they are not allowed to repair the boards. Just sell new ones.
I wont have any Mod or part #'s from the board until I pick it up later today
Thanks in advance for any help.
Manuel

Ask over at http://www.weldingweb.com
There are a few members over there that will be able to help you.

Pull the board out and see if you can read the part number of the pot. Check on-line to find the part and a little soldering to change. Don't use too much heat on the board. Remember, it's soldering and not welding. The new pot shouldn't be more than $5.

joseph.mowery wrote:Pull the board out and see if you can read the part number of the pot. Check on-line to find the part and a little soldering to change. Don't use too much heat on the board. Remember, it's soldering and not welding. The new pot shouldn't be more than $5.

Good advice but if that doesn't work, get the part nr from Lincoln and then find it on Ebay. I replaced the mainboard on my Miller 212 with a used one I found on Ebay. It's usually just a plug and play replacement job.

Just wanted to see if you we're able to get the circuit board repaired for your Lincoln 185. I have one with a bad board as well, with a different problem. If you replaced yours, I would be interested in buying yours for the part that I need. If not I will be buying a new board and mine will be for sale which has the good encoder that is bad on yours.

Hey, Manuel,

Do you have a Vocational-Technical school near you? If so, talk to an electronics instructor. Might get it in as a project for someone. If you're right, and it's just the pot., that's easy enough to prove, even without removing it from the board. A Vo-Tech school might fix it for the cost of parts, just to have a practical project.

Steve S

For all that are having this issue with the G4551 circuit board form a Lincoln precision tig 185.
I am an independent electronic technician and senior advisor on electronic comment repair. I can repair these boards, that's not a problem. The trouble is parts availability. The most common trouble with these circuit boards is that the digital display seems to "flake out" when trying to adjust the current Output using the control On the front of the unit. This control mom is not a pot, or potentiometer like most people think. It is in fact what's called an optical encoder. This is an optical device that uses a micro Hall effect style sensor to send the necessary information (pulses) to the microprocessor raising and lowering The output amperage current. This is why as you turn the knob it has no stop on it like a conventional pot would. It simply continues to spin, sending these pulses. If the G4551 model number on the circuitboard is followed by a –1 this is the earlier version of the board and was the most problematic. The new, revisied, circuitboard is the G4551-2. As I mentioned above I personally own one of these machines that has a bad circuit board. Mind however has a bad microprocessor, which can be purchased And replaced with a new one but needs to be flashed with the software from Lincoln. Lincoln however is no longer offering the service and requires you to buy the entire board. Therefore I'm in search of a bad circuitboard. Most liklely one with a bad encoder. If I'm forces to buy a new board, then I will have a donor board for any of you needing an encoder replaced. If you have a bad board to sell or would like your encoder replaced feel free to contact me I can do the repair as well.

BK

us4keys@aol.com

I know I'm late to the party but, for anyone still having a problem, I was having a similar problem. The amps would jump all over the place when I turned the dial.

I replaced the encoder with P/N: 652-PEC12R-4225F-N24 from mouser electronics

It seems to work fine now

Board number on mine is G4551-1B2 if that makes a difference