Lincoln Electric SQUARE WAVE TIG 255 IM520-B - Manual (Page 11)

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INSTALLATION
TABLE 1
Cable Sizes for Combined Lengths of Copper
Electrode and Work Cable
Machine Size
Lengths up to
100 ft 100 to 200 ft 200 to 250 ft
255 Amp
40% Duty Cycle #2 (35mm2) #1 (45mm2) 1/0 (55mm2)
Welders are shipped connected for the highest input
voltage as listed on the rating Plate. To change this
connection for a different input voltage, reconnect the
power strap (P) to the terminal corresponding to the
input voltage used. Designations on reconnect panel,
LOW, MID and HIGH correspond to the nameplate
input voltages of a triple voltage welder. Dual voltage
welders use only LOW and HIGH. Single voltage
welders use only HIGH.
EXAMPLE: On a 208/230/460 volt welder, LOW is
208V, MID is 230V, and HIGH is 460V.
Fuse the input circuit with the recommended super lag
fuses or delay type
1 circuit breakers. Choose an input
and grounding wire size according to local or national
codes, refer to Specification page at the beginning of
this chapter. Using fuses or circuit breakers
smaller than recommended may result in “nuisance”
shut-offs from welder inrush currents even if not
welding at high currents.
Unbalanced AC TIG welding draws higher input
currents than those for stick, DC TIG, or Balanced AC
TIG welding. The welder is designed for these higher
input currents. However, where unbalanced AC TIG
welding above 180 amps is planned, the higher input
currents require larger input wire sizes and fuses.
Refer to Specification page at the beginning of this
chapter.
The Square Wave TIG 255 should be permanently
wired into the power system. No plugs or connectors
are necessary.
1Also called “inverse time” or “thermal/magnetic”
circuit breakers; circuit breakers which have a delay
in tripping action that decreases as the magnitude
of the current increases.
FIGURE 2 - FRONT PANEL
1. CONTROL AND DISPLAY AREA 5. OPTIONAL WATER SOLENOID
2. POWER SWITCH 6. GAS SOLENOID
3. THERMOSTATIC 7. WORK (LEFT) AND
PROTECTION LIGHT ELECTRODE STUDS
4. POLARITY SWITCH 8. REMOTE RECEPTACLE
TIG TORCH CONNECTION
TIG welding torches come with 12.5 ft (3.8m) and 25 ft
(7.6m) cables. Use the shorter length whenever
possible to minimize possible radio interference
problems. With power source off, connect the torch
cable to the “Electrode” stud on the welder. Connect
a separate work cable to the “Work” stud of the
welder. See Table 1 for recommended work cable
sizes. Both work and electrode cables should be
routed through the cable strain relief holes provided in
the base directly below the welding output terminals.
TIG torches include the necessary gas and, when
designed for water cooling, water hoses. Connect the
fittings on these hoses to the welder fittings. Any torch
conforming to Compressed Gas Association (CGA)
standards can be connected.
D C
D C
A C
O
I
P O W E R
W A R N I N G
E L E C T R O D E W O R K G A S I N O U T W A T E R I N O U T
D O N O T S W I T C H W H I L E W E L D I N G
L 9 1 1 9 - 1
L 9 1 1 9 - 2 R E M O T E
1
2 3
4
5 6
7
8
OUTPUT CONNECTIONS
To avoid receiving a high frequency shock, keep the
TIG torch and cables in good condition.
___________________________________________
See Figure 2 for the location of the work and
electrode terminals, the gas and optional water
solenoids, and the Remote Receptacle.
WARNING