Operation, Welding operation – Lincoln Electric INVERTEC SVM129-B User Manual
Page 17
OPERATION
B-5
B-5
INVERTEC® STT® & STT® II
6. WIRE SIZE SELECT SWITCH: This toggle switch
selects between electrode diameters of .035” (1 mm)
and smaller or .045” (1.2 mm) and larger. The .035”
(1 mm) position provides improved performance of
smaller diameter wires at higher wire feed speeds.
7. WIRE TYPE SELECT SWITCH: This toggle switch
selects between mild or stainless steel. In the stain-
less position, the pulse width of the Peak Current is
changed from 1 to 2 ms for better performance for
stainless steel welding.
8. THERMAL SHUT-DOWN INDICATOR: This
light will indicate that either the internal ther-
mostat(s) or the FET over current sensor
has actuated. Machine output will return
after the internal components have returned to nor-
mal operating temperature (if the thermostat(s)
“opened”) or after about 3-7 seconds (if the FET over
current sensor activated).
9. REMOTE RECEPTACLE: This is a 10 pin MS-type
connector for remote control of Peak Current and
Background Current. Trigger switch connections
are also provided. The presence of the mating con-
nector is automatically sensed, disabling the front panel Peak
and Background Current controls. Refer to “REMOTE CON-
TROL CONNECTOR” in the ACCESSORIES Section of this
manual for more information.
10. WIRE FEEDER RECEPTACLE: This is 14
pin MS-type connector for the wire feeder
connection. 115 and 42 VAC along with
the trigger switch connections are provid-
ed. (Only 42 VAC is available on European mod-
els). There are no provisions for voltage control of
the power source by the wire feeder. Refer to the
Accessories section of this manual for wire feeder
connection instructions.
11. ARC SENSE RECEPTACLE: This is a four pin MS-
type connector for WORK and ELECTRODE sense
leads. The STT requires a WORK sense and ELEC-
TRODE sense lead for proper operation. The
ELECTRODE sense lead is bolted together with
power source electrode lead at the wire feeder gun
block. The WORK sense lead is furnished with an
“alligator” type clip for connection to the work piece.
Refer to the LN 742 or STT-10 wire feeder connec-
tion instructions in the Accessories section of this
manual for proper connection of these leads.
12. 42V AUXILIARY POWER CIRCUIT BREAKER:
The 42 VAC supply is protected from excessive current
draws with a 6 amp circuit breaker. When the
breaker “trips” its button will extend.
Depressing this button will reset the breaker.
13. 115V AUXILIARY POWER CIRCUIT BREAKER
(Not on European Models): The 115 VAC
supply is protected from excessive current
draws with a 6 amp circuit breaker. When
the breaker “trips” its button will extend.
Depressing this button will reset the breaker.
14. WORK TERMINAL: This twist-mate con-
nection is the negative output terminal for
connecting a work cable and clamp to the
workpiece.
15. ELECTRODE TERMINAL: This twist-mate
connection is the positive output terminal
for connecting an electrode cable to the
wire feeder conductor block. Refer to the
Accessories Section for wire feeder connection
instructions.
WELDING OPERATION
Familiarize yourself with the controls on the Invertec
STT II before beginning to weld.
Familiarize yourself with the operating manual for the
wire feeder and the wire feeder controls before begin-
ning to weld.
Set the Wire Size and Wire Type selection switches per
the appropriate wire. Refer to “Operational Features
and Controls” in this section for the function of these
switches.