disconnect the main power in an emergency. A typical
power supply installation is shown in Figure 3-9.
Machines that do not match the voltage supplied by
the utility may be used if a step-up or step-down
transformer is used. Figure 3-10 shows a step-down
transformer installed for this use.
Manufacturers have excellent warranties on their
products. Using a power supply voltage or fuses other
than the ones stated on the data label or instruction
manual may nullify a warranty.
Power Supply Maintenance
Given reasonable care and routine maintenance, a
welding power supply will operate for many satisfactory
hours before repairs are required. Modern methods of
insulating transformers, using good basic design and
solid-state components, have extended the hours of oper-
ation of a modern power supply. The manufacturer’s
instructions should always be followed for periodic
inspection of the power supply. The following points
should be observed along with the manufacturer’s
instructions:
• Turn the machine off and disconnect power at
the fuse box before working on it.
• Clean or blow out the unit on a periodic basis.
Use only dry filtered compressed air, nitrogen
gas, or an electrical nonconducting cleaner.
Always wear goggles or a face shield when
using compressed air or gas.
• Check all terminals for loose connections.
• Lubricate fan and motor bearings as required.
• Check mechanical arms and switches for freedom
of movement. Mechanical connections may be
lightly greased if required.
• Check terminal blocks for cable connections or
tap connectors. They should be clean and tight. If
corroded, they will restrict the flow of electrical
current. They may be cleaned by wire-brushing or
by rubbing with an abrasive pad.
• Check motor generator brushes, replacing them
when worn beyond the manufacturer’s tolerance.
Worn brushes wear armatures, which must then
be machined for proper operation.
• Lubricate, inspect, and adjust portable gasoline
and diesel power supplies, paying close attention
to the manufacturer’s instructions. This applies to
both the engine and the welder. Operation of
these units usually occurs under adverse condi-
tions. Improper maintenance will reduce the
capacity and operation of the unit.
Chapter 3 Equipment Set-up and Control 31
PALOMAR 63324COLLEGECOMMUNITY
TYPE SER. NO.
PART NO.
V-160
677936
L-12-852 INSTRUCTION
LITERATURE
INPUT OUTPUT
200/230 VOLTS 160 AMPS
60 HZ 1 PH 40 VOLTS OC
200/31-230/29 AMPS
35%
DUTY CYCLE
UNION CARBIDE CORPORATION
PROPERTY OF
Figure 3-8. The data label lists the requirements for incoming
power and the rated output power for the power supply.
Gas
supply
Primary
power
Fuse
box
Earth
ground
2
1
3
6
5
4
1. Locate power supply away from walls for proper air flow.
2. Locate primary fuse box near power supply.
3. Connect power supply frame to earth ground.
4. Connect work ground with 2/0 min-4/0 max cable.
5. Keep power supply dry.
6. Keep area near power supply clean.
Figure 3-9. A typical power supply installation includes a fuse
box mounted near the welder. An earth ground from the power
supply protects the welder from primary line high voltage.
Figure 3-10. These transformers change incoming primary power
to match the welding equipment’s power supply requirements.