flow chart - MK Products

5 FLOW CHART 5SYMPTOMNO WIRE FEED AT TORCH, FEEDER OPERATING PROPERLYPROBLEM AREACOBRA MAIN BOARD, TORCH POT OR TORCH MOTORSTARTNOIS COBRA MAINBOARD F1 FUSE OK?YESGO TO FLOW CHART #3COBRA I MAIN BOARD,F1 FUSE IS BLOWNCHECK FOR LOOSE CABLESAT COBRA FRONT PANEL ANDMAIN P.C. BOARDYESIS THE TORCH WORKINGOK NOW ?NOSYSTEM OKCHECK TORCH POT(SEE NOTE 1 BELOW)NOWAS METER READING OK ?YESCABLE IS BROKENORTORCH POT IS DEFECTIVECHECK TORCH MOTOR(SEE NOTE 2 BELOW)NOWAS METER READING OK ?YESCABLE IS BROKENORTORCH MOTOR IS DEFECTIVECOBRA MAIN BOARDIS DEFECTIVENOTES:1. Check TORCH POT at plug connector2. Check TORCH MOTORa. Testing the poteniometer - "W"Clocked. - Using Ohm Meter to checkresistance across pin "D" (wiper) and pin"C" of Torch plug. Should vary from 0 to5k ohm while turning pot. - Using Ohm Meterto check resistance across pin "D"(wiper) and pin "G" of Torch plug.Should vary from 0 to 5k ohm whileturning pot.b. Testing the poteniometer - "S"Clocked. - Using Ohm Meter tocheck resistance across pin "D"(wiper) and pin "C" of Torch plug.Should vary from 0 to 5k ohm whileturning pot.- Using Ohm Meter tocheck resistance across pin "D"(wiper) and pin "A" of Torch plug.Should vary from 0 to 5k ohm whileturning pot.a. Unplug the Torch from the front panel.b. Using the Ohm Meter, Check theresistance across pin "A" and pin "B"(motor leads) of Torch plug. The resistanceshould be about 5 to 10 ohms.c. If open of short circuit exists, then checkmotor leads and motor for additional problems.CobraMig 260 Owner's Manual - Page 24