MK Products CobraMig 260 PS/Feeder - Manual (Page 32)

CobraMig 260 Owner's Manual - Page 26
FLOW CHART
NO
YES
SYMPTOM
NO WELD OUTPUT, NO VOLTAGE CONTROL
PROBLEM AREA
POWER SUPPLY CONTROL (PSCB), THERMOSTAT, TRIAC, CONTACTOR SIGNAL,
PWR SWX BOARD
START
YES NO
NO
IS PSCB LED D12 ON ?
PSCB IS DEFECTIVE
YES
YES
REPOSITION JUMPER TO TP2
AND TP3
ADD SECOND JUMPER TO TP1
AND TP5
YES
IS WELD OUTPUT AT MAXIMUM
(APPROX. 35 - 40VDC)
NO YES
DOES OUTPUT VARY WHEN
VOLTAGE KNOB IS TURNED
APPROX :LO 10 - 32VDC
HI 29 - 40VDC
K2 RELAY ON
COBRA I MAIN
BOARD DOES NOT
SEND CLOSING
CONTACT SIGNAL
OR TORCH SWITCH
IS DEFECTIVE
THERMOSTAT
TERMINALS LOOSE OR
THERMOSTAT IS
DEFECTIVE
(OPEN ALL THE TIME)
TRIAC RESISTANCE CHECK:
Use meter in "Diode" mode.
Pin 3 to Pin 4 : 2.3
Pin 1 to Pin 2 : open
NO
NO
PSCB IS DEFECTIVE
7 7
IS PSCB F1 FUSE OK ?
TRANSFORMER RELAY
IS DEFECTIVE OR NO AC
INPUT, CHECK
DISCONNECT FUSE
PSCB IS DEFECTIVE
IS PSCB LED D7 ON ?
(DOES IT HAVE 12 VOLTS)
JUMPER TP1 TO TP5 ON PSCB
REPOSITION JUMPER
TO TP2 AND TP4
USING VOLTMETER, MEASURE WELD VOLTAGE
AT COBRA I MAIN BOARD J6-1(+) AND J6-2(-)
DOES OUTPUT VARY WHEN VOLTAGE
KNOB IS TURNED
APPROX :LO 10 - 32VDC
HI 29 - 40VDC
TRIAC IS DEFECTIVE