Arc Machines 307 - Manual (Page 10)

Arc Machines, Inc. Model 307 Orbital Tube Welder Training
Document No. 740096 Chapter 2. Page 1.
Rev. A
C
hapter 2.
S
afe Operating Procedure -
S
afety Precautions for Model 307 Operation
THE ELECTRODE SHOULD ALWAYS BE
CONSIDERED A POSSIBLE SHOCK HAZARD .
This is especially true whenever the system is:
• IN SEQUENCE
• READY TO WELD,
• IS WELDING,
• OR HAS JUST FINISHED WELDING.
When replacing or adjusting the electrode:
• Set power supply to “TEST” mode
Most AMI Power Supplies feature RF (radio frequency) Arc
Starting. This is a High Voltage/High Frequency electrical trans-
mission process. The GTAW process requires electrical potential
(high voltage) to be present on the electrode and on exposed
internal terminals during arc starting and during welding. ALL
AMI Power Supplies contain a “bleeder” circuit to ground any
residuals or potential after welding or after an aborted or bad
“arc start” attempt. However, these circuits take a few seconds
to operate or could fail.
Electrode installa-
tion in a Model 8
weld head.
AVOID ALL
CONTACT
WITH THE
WELDING
WORK
(GROUND) OR
ELECTRODE
DURING ARC
START