Miller Electric Inverter Rack - Manual (Page 19)

OM-818 Page 15
3-8. Paralleling Welding Power Sources For SMAW
ST-801 701
Y Turn Off welding power sources by
placing Power circuit breakers in the
Off position before making any weld
output connections.
Y Do not connect welding output of dif-
ferent polarities to the same
structure.
Y See ANSI Z49.1 and OSHA Title 29,
Chapter XVII, Part 1910, Subpart Q
(addresses at beginning of manual).
Y Do not handle or come in contact with
two live electrodes at the same time.
Y UNDERSIZED WELDING CABLES
can cause fire. Use single cables of
adequate capacity to carry the total
combined amperage of the paralleled
welding power sources
Y ARCING can burn skin or damage
electrical equipment. Do not change
position of the welding cable connec-
tors while welding.
Y Be sure the connectors are secure in
receptacles before welding.
Y INADEQUATE WORK CABLE CON-
NECTIONS can cause serious dam-
age to input power service and create
a hazardous condition. Connect an
electrical cable of adequate size be-
tween the isolated terminal and the
workpiece whenever the isolated ter-
minal is used.
Set the Amperage/Voltage control on all par-
alleled welding power sources to the same
value. The isolated terminal may be used as
a common connection point if no other con-
nections are made to it.
The procedure shown is for Electrode Posi-
tive 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 connection.
4 Common Weld Output Cable
Cable must be able to carry combined weld
output of all welding power sources con-
nected in parallel. Use Section 3-6 to select
proper cable size.
For Electrode Negative, reverse cable con-
nections. Positive (+) weld output cables con-
nect to work, negative (−) weld output cables
go to electrode.
3
4
Securely cover connection
with proper insulating
material.
1
1
4
1
4
2