B-3
OPERATION
B-3
7. OUTPUT TERMINALS
-
These quick discon-
nect terminals are compatible with
TWECO®*
con-
nectors. The terminal provide connection points for
the electrode and work cables. Refer to
Output
Connection
in the Installation chapter for proper
cable sizes. For positive polarity welding connect
the electrode cable to the positive terminal and the
work cable to the negative terminal. To weld nega-
tive polarity reverse the electrode and work cables.
* TWECO
®
is registered trademark of Thermo Dyne Corporation.
8. THERMAL SHUTDOWN INDICATOR
-
This light will illuminate if an internal thermostat
has been activated. Machine output will return after
the internal components have returned to a normal
operating temperature. See
Thermal Protection
later in this Operation chapter.
9. 3-PIN REMOTE RECEPTACLE
3-Pin remote control allows for remote control of
the Output current.
10. POWER LIGHT
- This Light will illuminate
when the power switch is in the
“
ON
”
Position.
CONSTANT CURRENT PROCESSES
STICK WELDING*
The Invertec may be utilized as a manual DC arc
welder with the electrode cable, work cable, and elec-
trode holder being the only equipment required.
AIR CARBON ARC CUTTING*
Air carbon arc cutting may be performed with the
Invertec within its output rating using 3/16
”
(4.8mm)
diameter carbon rods. Output cables, an air carbon
arc electrode cable assembly, and a source of com-
pressed air are required.
TIG WELDING*
The ES 275i is capable of touch start TIG welding. An
electrode cable, work cable, TIG torch, and gas sup-
ply with regulator are required.
Touch starting is done as follows:
1. Place the shield cup edge on the work piece.
2. Rock the tungsten down to touch.
3. Gently rock back the tungsten from the work-
piece.
Note
: The short circuit current is limited to 20 amps to
aid in touch starting. Panel output control
becomes the current limit setting when in
remote control.
*Note
: Operating this machine with the output control
set to maximum may cause the machine to
phase back and the arc to go out. This occurs
because the welding current exceeded 300
amps and the machine
’
s protection circuitry
activated. Turn the output control down to cor-
rect this condition.
PARALLEL OPERATION
The Invertec
’
s are operable in parallel. For best
results, the currents of each machine should be rea-
sonably well shared. As an example, with two
machines set up in parallel for a 300 amp procedure,
each machine should be set to deliver approximately
150 amps, not 200 amps from one and 100 amps
from the other. This will minimize nuisance feedback
conditions. In general, more than two machines in par-
allel will not be effective due to the voltage require-
ments of procedures in that power range.
To set machine outputs, start with output control pots
and arc force pots in identical positions. Adjust out-
puts and arc forces to maintain current sharing while
establishing the proper output current.
ES 275i
