Miller Electric XMT 4-Rack - Manual (Page 13)

OM-815 Page 9
4-5. Paralleling Welding Power Sources For SMAW
ELECTRIC SHOCK can kill.
•
Do not touch live electrical parts.
•
Turn Off welding power sources by placing Power
circuit breakers in the Off position before making any
weld output connections.
•
Do not connect welding output of different polarities
to the same structure.
•
See ANSI Z49.1 and OSHA Title 29, Chapter XVII,
Part 1910, Subpart Q (addresses at beginning of
manual).
•
Do not handle or come in contact with two live
electrodes at the same time.
UNDERSIZED WELDING CABLES can
cause fire.
•
Use single cables of adequate capacity to carry the
total combined amperage of the paralleled welding
power sources.
ARCING can burn skin or damage
electrical equipment.
•
Do not change position of the welding cable
connectors while welding.
•
Be sure the connectors are secure in receptacles
before welding.
INADEQUATE WORK CABLE
CONNECTIONS can cause serious
damage to input power service and
create a hazardous condition.
•
Connect an electrical cable of adequate size
between the isolated terminal and the workpiece
whenever any welding power sources are
connected to the isolated terminal.
WARNING
Set the Amperage/Voltage control
on all paralleled welding power
sources to the same value. The iso-
lated terminal may be used as a
common connection point if no
other connections are made to it.
The procedure shown is for
Electrode Positive welding
connections.
1 Weld Output Cables
Determine cable sizes according to
welding power source Owner’s
Manual. Cables must reach cable
connection point. Cables con-
nected together must be the same
polarity.
2 Connection Point
Cover with proper insulating
material after making connections.
3 Terminal Lugs
Use lugs of proper amperage
capacity and hole size for connec-
tion.
4 Common Weld Output Cable
Cable must be able to carry com-
bined weld output of all welding
power sources connected in paral-
lel. Use Table 4-1 to select proper
cable size.
For Electrode Negative, reverse
cable connections. Positive (+)
weld output cables connect to work,
negative (–) weld output cables go
to electrode.
ST-158 334 / Ref. ST-154 540-A
1
1
2
SMAW
+
–
3
4
Securely cover connection
with proper insulating
material.
4
1
4
Figure 4-5. Paralleling Welding Power Sources For SMAW