Arc Machines 227 - Manual (Page 80)

MODEL 227
OPERATION MANUAL
Doc # 740063 Rev E
SECTION VII - CALIBRATION
7.6 SYSTEM FAULT CORRECTIONS
8. HIGH VOLTS - If the arc voltage gets too high during a weld sequence this fault
will occur. It usually occurs if a hole should be made in the weld and the arc can
extend over to the opposite side of the weld, Check the weld procedure and the
arc gap required for the weld. This FAULT can be “turned off” by use of the set
up screens.
Turn this feature OFF when MANUALLY welding or when using large ARC
Gaps (0.050”) and low current in HELIUM or HELIUM mixed gases . These
conditions tend to create very high ARC Voltages and could cause an undesirable
FAULT if this option is left ON.
9. BAD START - If for any reason the M-227 cannot achieve a stable Arc at the end
of PREPURGE the system will display this statement.
There can be several reasons for this to occur. The most common are poor cable,
ground and electrode connections, bad gas, bad tungstens, dirty tungstens, etc.
The RF is transmitted from the M-227 to the electrode, if anything creates
resistance or an alternate path for the RF the start can be weak.
When a BAD START occurs check the electrode connection and electrode
condition first. Also check to insure that CERRIATED electrodes are being used.
They have proven to be much more effective than THORIATED electrodes for
RF transmission and longer life.
BAD STARTS can also be caused by not having the START LEVEL set. See
Section V for START LEVEL information.
RF starting problems can be very difficult to solve because of all the items that
can cause problems. If continued RF problems occur call the AMI Service Dept.
for help in finding the problem .
CAUTION
Another cause for a BAD START indicator is to press Sequence Start near the end
of the POSTPURGE but before “Return to Home” and system reset. The M-227
will sometimes try and strike another arc. ALWAYS ALLOW THE M-227 TO
FINISH AN OPERATION COMPLETELY BEFORE ATTEMPTING TO
START ANOTHER.
10. NO DISPLAYS/DISPLAYS SCRAMBLED - The LVPS FAULT is meant to
detect Low Voltage. However, if the Voltage is really low the Displays will not
even turn on or the information being displayed can be scrambled.
7.10