XMT304 Problem. Need Help Please!!!

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Hi everybody.  I'm new to the forum but I have tried my best to find an answer to my problem before asking.  I bought a used miller XMT 304 CC/CV 1/3 phase off ebay and have not been able to get it to work.  For the time being I had it wired to the dryer plug in the garage.  After plugging it in and turning it on I noticed that no matter what process it was on it wouldn't hold a constant voltage or amperage most of which did not read any volts or amps at all.  The ones that did jumped high and low all over the place.  I tried hooking up the leads to it and had no output whatsoever.  Has anybody had this problem or any ideas of what could be wrong?  The ebay seller said it had been tested and everything was good to go.  Any and all help would be much appreciated. Thank you.
Reply:I forgot to mention that there are two reset buttons on the back of the machine. One of them pushes in and comes back out but the other stays in and will not pop back out. Could that have anything to do with it?
Reply:Have you tried welding with it?-DaveXMT304 with: 22A Feeder, or HF251 Hi Freq DC TIG air cooled
Reply:Originally Posted by davecHave you tried welding with it?
Reply:I put a post on miller's forum too and one guy said to wire it 220 with two hot leads and a ground, don't use the neutral.  Any thoughts about that?  Good idea, Bad idea?
Reply:Did you read the owners manual?Find it here.http://www.millerwelds.com/service/o...uals.php?modelAre you sure it is a 220V capable machine? See serial number and owners manual. Attached Images
Reply:how do you have it wired now?
Reply:Yes I have checked the serial number and from what I understand it should work on 220.Here are some pictures of how it is wired.  On the plug end i have the black and white wires on the side posts and the green ground on the center post.  Sorry, some of the pictures came out sideways. Attached Images
Reply:It appears to me that this is not wired correctly. According to the manual for that machine when it is wired for single phase the red wire is not connected. From the pics it appears that you are connected to the red wire. I am not sure as I am not that familiar with this machine.
Reply:Originally Posted by leightrepairsIt appears to me that this is not wired correctly. According to the manual for that machine when it is wired for single phase the red wire is not connected. From the pics it appears that you are connected to the red wire. I am not sure as I am not that familiar with this machine.
Reply:Is your picture the backside of the power switch?
Reply:Originally Posted by leightrepairsIs your picture the backside of the power switch?
Reply:There should be a black white and red from the machine going to the switch. for 220 single phase you need to connect the black and white to the incoming lines and ground to the green. The red wire at the switch is only used if you are connecting to 3 phase power. You may want to have this machined checked by your LWS, i don't know if hooking it as you have will have caused any damage.
Reply:Originally Posted by leightrepairsIt appears to me that this is not wired correctly. According to the manual for that machine when it is wired for single phase the red wire is not connected. From the pics it appears that you are connected to the red wire. I am not sure as I am not that familiar with this machine.
Reply:I only see a black and a red wire going to the switch
Reply:The power cord for that machine when miller shipped it out had a cord with black, white red, and green conductors. The black white and red = L1, L2, and L3, the green for ground. Black (L1) and White (L2) are the inputs for 220 single pass. If you have three phase power then the red would be connected to L3. The green is always connected for ground. If you look on pg 15 of the manual it shows the wire configuration and pg 24 has the schematic. You may want to get an electrician to wire this machine, his bill may be cheaper then having to repair/replace the welder.
Reply:Originally Posted by leightrepairsThe power cord for that machine when miller shipped it out had a cord with black, white red, and green conductors. The black white and red = L1, L2, and L3, the green for ground. Black (L1) and White (L2) are the inputs for 220 single pass. If you have three phase power then the red would be connected to L3. The green is always connected for ground. If you look on pg 15 of the manual it shows the wire configuration and pg 24 has the schematic. You may want to get an electrician to wire this machine, his bill may be cheaper then having to repair/replace the welder.
Reply:simple fix. find the red ,white and black wires from the power pcb and connect them to the switch. Then connect your line power cord white to white and black to black. leave the red.Putting power on the red and black wires to the power pcb will only power the board. You need power on the black and white power board wires to power up the control circuits.The aux power transformer is connected to the white and black circuit. the auto link circuit connects the aux transformer and the weld caps for the proper line voltage.Be careful there is very high voltage on the power pcb and when thing fail they can blow up. It is best to have the cover on when powering up the welder.Last edited by ccawgc; 04-23-2012 at 12:09 AM.
Reply:Go ahead and make sure it is wired up like in the manual (internally black and white wires go to the external black and white wires and the greens are connected as well.   Green wire should be the center pin of the dryer plug, blank and white the two outer.  It doesn't matter which one is black and which one is white.However, internally the three wires black, white, and red are wired to a 3 way bridge rectifier.  I don't think it makes any difference which legs you pick.  If it does make any difference, it will be something subtle and small like black and white pair can handle 1% more heat.Set it to stick mode and try to weld with it.  Grab soem 6013 and look at the package and turn it up to the max for that diameter.  6013 is typically an easy rod to start (drag + scratch start).  In stick mode, the Amps should be relatively steady.  Volts should be all over the place (Maybe on that machine the volts are darkened).Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX