EXCEL-ARC 500, 6045
5-4
August 22, 2005
5.05 Detailed Troubleshooting
Instructions
The first step in troubleshooting this power source should
be to eliminate any external equipment or conditions as
the source of the problem. The following can be used as
a general guideline for troubleshooting:
· Are any cables frayed or damaged or connections
loose?
· Is the gun liner worn or plugged?
· Are the drive rolls tight?
· Does the wire feed smoothly, is the gun cable
kinked?
· Check for worn contact tubes (tips)?
· Is the machine set correctly, or has a setting been
changed?
· Is the shielding gas flow correct?
· Is the line voltage correct for the machine, blown
fuses?
· Is the air flow in and around the machine
unobstructed?
Once external conditions have been eliminated as the
source of the problem the following guide can be used
for specific checks on the machine. As in the case of all
electrical equipment, loose connections can often be the
cause of malfunction. Examine the machine for any loose
or broken connections internally especially connections
to the control circuit board. To gain access to the control
board, remove the control panel from the front panel of
the power source.
1. Control Board 830267:
All readings taken at nominal line voltage with maximum
OCV on the machine.
Test Point
Expected Reading
Remark
R192 to TP19
17 VAC
AC voltage input to board
R193 to TP19
17 VAC
AC voltage input to board
R194 to TP19
17 VAC
AC voltage input to board
R195 to TP19
17 VAC
AC voltage input to board
R196 to TP19
17 VAC
AC voltage input to board
R197 to TP19
17 VAC
AC voltage input to board
TP16 to TP19
+18 VDC
Power Supply
TP17 to TP19
-15 VDC
Power Supply
TP18 to TP19
+15 VDC
Power Supply
TP11 to TP19
+10 VDC
Reference voltage
TP1 to TP19
0 VDC (for no Arc established)
Arc Established signal for 1>30 Amps TP1 = +14 VDC
TP2 to TP19
+5.4 VDC for CV
Vfb = Varc/10
+6.2 VDC for CC
TP3 to TP19
+8.8 VDC for CV
Firing angle control signal
+13.5 VDC for CC
TP4 to TP19
0 VDC (for gun switch on)
Gun Switch signal
TP6 to TP19
0 VDC
IFB = 1V per 100 Amps
TP7 to TP19
-9.56 VDC
Negative reference voltage
TP8 to TP19
+4.4 VDC for CV
SCR gate signal
+11.65 VDC for CC
TP9 to TP19
+4.4 VDC for CV
SCR gate signal
+11.65 VDC for CC
TP10 to TP19
+4.4 VDC for CV
SCR gate signal
+11.65 VDC for CC
TP12 to TP19
+14.6 VDC
SCR gate signal
TP13 to TP19
+14.6 VDC
SCR gate signal
TP14 to TP19
+14.6 VDC
SCR gate signal
Table 5-2: Test Points
