General Description; Recommended Processes; Operational Features And Controls; Design Features And Advantages - Lincoln Electric SQUARE WAVE IM467-B Operator's Manual

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GENERAL DESCRIPTION

The Square Wave TIG 355 is a constant current, single
range square wave AC/DC TIG (GTAW) arc welding
power source with built-in high frequency stabilization.
It also has stick (SMAW) capability. The Square Wave
TIG 355 gives the operator full control of the welding
current plus the ability to preset weld and start cur-
rents. Preflow and postflow timers are included for
shielding gas and cooling water control. Altogether
the many features of the machine allow part or all of a
weld cycle to be preset or "programmed," which sim-
plifies the TIG welding process.
The Square Wave TIG 355 includes advanced features
such as Auto-Balance™ 2-Step/4-Step Arc Start
Switch Operation, start controls, crater controls, spot
timer, and status LEDs. Preflow and postflow timers
allow control of shielding gas and cooling water.

RECOMMENDED PROCESSES

The Square Wave TIG 355 is recommended for TIG
(GTAW) and stick (SMAW) welding processes within its
output capability of 2 to 400 amps on both AC and DC
polarity. It is compatible with all Magnum TIG acces-
sories as well as many industry standard TIG torches,
hoses, and water coolers. (See the Accessories sec-
tion of this manual.)
OPERATIONAL FEATURES AND
CONTROLS
The following operational controls are standard on the
Square Wave TIG 355: Local/Remote current control
switch, Stick/TIG mode selection switch, TIG 2-
Step/TIG 4-Step mode selection switch, High
Frequency Continuous/Start/Off switch, Peak Current
control, Volts/Amps switch for the digital ammeter
reading, AC Wave Balance control, Afterflow timer for
shielding gas and water flow, Arc Force current control
for stick welding, Preflow timer for shielding gas and
water flow, Spot Time Controls, Start current/time
controls, Pulse controls (pulses per second, back-
ground % peak current, pulse % on), and Crater Fill
controls (fade-out, % peak current).
The following additional features are also standard:
Digital ammeter selectable for either volts or amps;
Status Indicator LEDs for gas and water, high frequen-
cy, arc established, start, peak, background, crater fill.
OPERATION

DESIGN FEATURES AND ADVANTAGES

• Designed to NEMA EW-1 and International IEC-974
Standards.
• Single output range of 2-400 amps covers the
majority of TIG welding applications.
• Solid State Output Contactor: no noise, no parts to
wear.
• Digital Ammeter and Voltmeter for precise readings
from 2-400 amps welding.
• Welding current limit can be preset from 2-400
amps and is displayed on the ammeter when not
welding.
• Auto Balance™ circuitry automatically provides the
proper amount of cleaning and penetration when
AC TIG welding. Manual AC wave balance adjust-
ment is also possible.
• 2-Step/4-Step Arc Start switch capability.
• Spot control for 2-Step Arc Start switch mode.
• TIG Pulser with On/Off selection, and Pulses Per
Second adjustment. Background current and duty
cycle are automatically adjusted according to the
peak welding current.
• Crater Fill control for current fade-out at the end of
a weld.
• Adjustable preflow time from 0 to 10 seconds.
Preflow time is eliminated if welding restarts during
gas afterflow of previous weld. This avoids unnec-
essary delays when making repeated welds.
• Adjustable afterflow time control.
• Locate/Remote current selection.
• Stick/TIG selection.
• Arc Force control of added current when electrode
shorts to the work in stick mode.
• Continuous/Start/Off High Frequency selection.
• DC+/AC/DC- Polarity switch.
• Power Factor Correction for lower input currents
and smaller input wire sizes.
• Remote Receptacle for Amptrol™ or Arc Start
switch.
• Low Voltage Arc Start switch circuit (24 VAC) for
maximum operator safety.
• Gas and optional water valves: Inlet and outlet fit-
tings conform to Compressed Gas Association
(CGA) standards.
• Built-In High Frequency Generator.
SQUARE WAVE TIG 355
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