Lincoln SP100...Think Main Board is Bad...

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Somebody gave me an SP100.  The Fan was hooked up backwards so I think it Burned up the Main Board and Fan.The fan worked for a second after pluggin it in and then something made a small popping noise and then a bad smell came from the Welder.Thoughts?Here are some Pictures of what I have...Last edited by A2brb1; 08-08-2007 at 11:37 PM.
Reply:Popping is bad.  Must have been a new fan for it to have been hooked up backwards, if possible at all. I don't see how a fan could affect the board. They just aren't made that way unless there's a built in disconnect so if the fan fails the machine won't run. Glancing at the board I don't see anything obvious that would have been this "pop". Flip the board over to the non circuit side and look for burnt/hot spots.
Reply:The fan's looks like and ac motor should work hooked up either way.  Look for obvious cooked components.  The board looks ok in the picture check it closely.  Did the welder shut off after the popping sound?
Reply:Yes, it shut right off after the popping sound.  I will look around on the board more closely.  I was told by a local shop that there is only one way to hook up that fan.
Reply:Without a code number and wiring diagram, I can't tell for sure, but that motor could very well have a 24VAC winding to supply control voltage.  (there appear to be 4 connections) If that 24VAC winding were connected to the 115VAC input, the motor winding likely would have gone "pop".  You may just need another motor.Good luck,Bob
Reply:Thanks for the help.  I looked around on the Main Board and didn't see anything out of the ordinary...No burn spots etc..Keep in mind...the Fan Ran for a few seconds and then something popped and a wierd smell cam from the Welder.  No smoke.For another Check....I plugged in the welder and turned it on....Nothing...No wire feed etc.  The Fan motor is unplugged.  Would the fan need to be plugged in to engage the rest of the system??Yes, there are 4 wires that connect from the motor into the system.The part number for the Motor is: M15787-1Here is a pic of the wiring Diagram on the Welder.Last edited by A2brb1; 08-10-2007 at 05:47 PM.
Reply:That diagram does show a 24VAC winding in the fan motor that supplies power to the PC board.  You will probably need to replace the motor, or find another 24VAC power source before you will be able to power the board and determine if the rest of the machine is functioning normally.  The fact that there is no visible damage to the board is certainly a good thing; lets just hope there is no hidden damage.Cheers,Bob
Reply:Originally Posted by BobCThat diagram does show a 24VAC winding in the fan motor that supplies power to the PC board.  You will probably need to replace the motor, or find another 24VAC power source before you will be able to power the board and determine if the rest of the machine is functioning normally.  The fact that there is no visible damage to the board is certainly a good thing; lets just hope there is no hidden damage.Cheers,Bob
Reply:Originally Posted by SandyTrying to interpret what BobC is saying here it sounds like the fan may be 120 vac with a step down xfrmr built in to provide 24 vac to power the board.
Reply:Thanks for the info Bob.  Could I hook up some type of device (Volt meter) to check the board? Originally Posted by SandyIn that case (in most cases actually) there should be a small fuse mounted on the PC board very near power input. .
Reply:Originally Posted by A2brb1Thanks for the info Bob.  Could I hook up some type of device (Volt meter) to check the board?I looked around on the Main Board for a fuse and couldn't find one.  Should I be looking for something like a fuse similar to the small replaceable fuses used in the Fuse box of an Auomobile?Where do you guys usually order parts from?
Reply:Originally Posted by A2brb1Thanks for the info Bob.  Could I hook up some type of device (Volt meter) to check the board?