Grizzly G0879, Owner'S Manual

Page: 15 / 36

Model G0879 (Mfd. Since 6/19)
-13-
Grounding for
Welding Safety
There are two or more electrical circuits involved
in any welding operation. The practice of safely
grounding these circuits is documented in vari-
ous codes and standards (refer to
Additional
Sources for Welding Codes and Standards on
Page 6).
Welding Machine Ground
When properly connected to a power source, the
Model G0879 welder is grounded through the
power cord and power grid. The internal welding
circuit of the welder is insulated from the external
enclosure. However, to avoid shocking hazards
if this internal insulation fails, you must establish
a separate earth ground for the welder's external
enclosure. This ground will ensure that if a short
does occur and the metal enclosure becomes
integrated with the welding current, the current
will safely dissipate directly through the ground
instead of through you.
Note: Refer to the publication NFPA 70, National
Electric Code, Article 250, Grounding, and your
local electrical codes for the correct method of
establishing this ground.
Workpiece Ground
The incoming power circuit to the welder and the
working welding circuit are two separate circuits
that must have separate grounds. The welding
circuit consists of the internal components of the
welder, the welding cables, the electrode holder/
gun assembly, the work clamp, and the workpiece.
ANSI Welding Standards (Z49.1, 11.3.2.1) specify
that "Grounding [of the workpiece] shall be done
by locating the work on a grounded metal floor or
platen, or by connection to a grounded building
frame or other satisfactory ground."
Always ensure that the ground for the
incoming power circuit to the welder and
the ground for the working welding circuit
are never connected. Failure to comply with
this warning could result in death, serious
personal injury, or property damage.
However, you must also avoid "double ground-
ing" the workpiece. ANSI Z49.1 states that "Care
shall be taken to avoid the flow of welding current
through a connection intended only for safety
grounding since the welding current may be of a
higher magnitude than the grounding conductor
can safely carry."
Note: The work lead from the welder is some-
times incorrectly referred to as the "ground lead."
The work lead from the welder is NOT a ground.
The work lead and the ground connection to the
workpiece are separate and must NOT be con-
nected in any way.
Wire-feed welders use a high frequency
current that creates a high electromagnetic
field (EMF) around the welder. EMF disrupts
electronic devices. To avoid damage, keep
electronic devices at least 50 feet from the
welder when it is powered ON. Workers who
have pacemakers must consult with their
physician before using this equipment or
being within 50 feet of welding operations.