millermatic 250X stopped working

[shytbox00]

millermatic 250X LB048853 circuit board #196456

i just picked up the welder used. came with the 30a spoolgun for aluminum. when i hooked it up for the first time at my house as soon as i struck an arc with the gun for steel it worked for a second and then cut out. i can hold the trigger down and gas flows but no power to the gun. no wire feed. nothing. i cut the wire and pulled it out. still nothing. jumped the 2 prong plug on the front of the machine for the gun and same problem. circuit breakers are fine. machine turns on just no power to the gun when i pull the trigger. jumpers are hooked up right for the voltage. i have it plugged into a 220 50amp receptical. i tried using the spool gun and that works fine. could the board still be bad?? board looks fine. the machine looks brand new. i dont want to send the board out for repair it thats not the issue. any help greatly appreciated. the machine worked flawlessly before i brought it to my house. coincidence?

[H80N]

have you downloaded and read the manual????????????

[shytbox00]

yes to no avail

[H80N]

and you have measured the input power inside the machine with a meter to make sure that both legs of the 230 are making it to the switch?? and past the switch when turned on??


and did you check the jumper block to make sure the machine is strapped for the right input voltage???

[duaneb55]

If you just dragged it home, double check all the board, relay and harness connectors to make sure none came loose during transport.

Make sure circuit breaker CB1 that provides power to the wire feed motor isn't open if you haven't checked it yet.

[shytbox00]

yes 230 at the switch and on the other side when turned on. jumpers are in the correct location for my set up.

double checked all the board, relay and harness connections and both breakers inside the machine are not tripped.

[H80N]

is Thermostat TP1 open...???? it might be defective.... making the unit think it is overheated.....???

[Rbeckett]

[QUOTE=shytbox00;277740]millermatic 250X LB048853 circuit board #196456

. i tried using the spool gun and that works fine. could the board still be bad??

Sounds like a bad connection either at the gun or the connector on the machine. If the Spoolgun is working fine then the machine is functioning and your losing something in the gun or connector more than likely. If it worked before you moved it look closely at the whip and all of those connections. Hope this helps get you going again.
Bob

[ccawgc]

If your welder welds correctly with the spoolgun and does not work with the miggun. Then we need to check the miggun trigger. Make sure it is not shorted to the weld conductor inside the miggun. If the trigger wires are shorted to the weld circuit, it is possible that the control pcb is now damaged.
The control pcb has two different trigger inputs. one for spool gun and one for miggun. It is possible to have one input get shorted out and the input transistor blown and still have the other trigger input still work correctly.
So before you put a new pcb in, make sure the miggun is not shorted or damaged.
If the above is all good, then check the power connector coming up from the transformer to the pcb. Should be 4 wires. check the plugs and splices.

[H80N]

Did you ever get to the bottom of this??

what is the status??........

[shytbox00]

ive been really busy the past couple days. i should be able to mess with it this week. ill let you guys know as soon as i get to check it out again. thanks.

[shytbox00]

looks like a bad board. any of you guys recommend a place to get a new one or this one fixed? i also heard about a chip that gets added to the board to take care of the burnback. let me know. thanks!

[shytbox00]

the board is a 196456

[cruizer]

just can't see the problem being the board, I can see the problem being a stuck or miswired CR2 relay though. The spoolgun part of it just takes the mig gun motor out of the circuit via CR2 relay. If it was stuck, all you'd get from hitting the mig gun trigger is the gas solinoid and open circuit voltage, no drive motor.