Legend aead 200 le no ac power or weld output

[blucky]

Did a tune up on my welder and tried to strike an arc, nothing. Checked for ac power, nothing. This was after I tried to install a new battery while it was running (bad idea). The motor died. I didn't think to much about it at the time and finished installing the battery and fired it back up. By unhooking the battery while running, did it cause a voltage spike and burn something out. I think I read somewhere that it may have caused the voltage regulator to burn out. Any help would be appreciated.

[snoeproe]

Let's start with the ac power first.
Did you check the fuses ?

[duaneb55]

There were several variations of the AEAD-200LE so a unit SN will be very helpful.

[blucky]

SN# KA816658. The only fuse I can find is on the right side of the welder behind the control panel. I think it is the F1 fuse. I checked it with an ohm meter and it checked good.

[blucky]

ttt

[duaneb55]

I suspect flashing diode D4 may have failed open (no continuity in either direction). It's located in the wiring harness and can be found by locating wire #27 at the ignition switch and following it to diode D4.

If in fact it's failed open, you can likely find a replacement at Radio Shack or other local electronics store. It's rating is 3A/1000V but a higher amperage rating can be used.


Oh, and don't unhook the battery while the unit is running.

[blucky]

I could not find #27 wire. The schematic showed wire #31 going to D4. My multimeter does not have a diode mode so I checked it on 2000k ohms. It read 1500 ohms. I don't know that much about testing this stuff so bear with me.

[duaneb55]

You're right - wire #31. My bad. Looking at the wrong schematic and even after asking for the unit SN.

If the machine has the optional remote control, check for a bad relay CR5 and for poor terminal connections at same.

[blucky]

We have power!!

Had to order D4 diode. Also ordered voltage regulator. Replaced both. Still had no power or weld out put. Regulator is charging battery at 14.35 volts. Scratched my head and wondered where to look next. Took brush holder loose to check brushes.
Brushes were fine. Inspected the wiring and found a spade terminal that had lost connection on one of the brush terminals for the left slip ring. Made sure all connections were tight and adjusted brushes. Fired it back up and checked power on the outlets. Woo hoo! 116v. Struck an arc, machine kicked up and welded a nice bead as good as it ever has. I have no idea how that terminal came loose since I had never had the covers off. Could have been years of vibration or someone could have changed the brushes and didn't get the terminals on good. Any way I have a working machine again. A big thanks to Duane for your help. Fixed for $30.