Instruction manual

39
4.2.2 PREFLOW/POSTFLOW/SPOT/BURNBACK (OPTIONAL) P/N-0558002889 (Figure 15)
This optional control is mounted in place of the standard burnback control inside the wire spool compartment. A description
of the module follows:
A. Preow/Postow - The PREFLOW control sets the time of the preow shielding gas before the wire starts feeding (0-1.5
sec.). The POSTFLOW control sets the time the shielding gas remains “ON” after the arc is turned “OFF” (0-7.5 sec.).
B. Spot Weld Time - This dial sets the spot weld time from 0 to 5 seconds and is controlled by a current detect switch. The
timer does not start until current is detected to insure consistent results.
Figure 15 - Preow/Postow/Spot/Burnback
C. Burnback Timer - See 4.1.11
D. Spot Weld Switch Position - With the toggle switch in the SPOT (left) position, the SPOT timer is turned “ON”, and the
spot weld time is controlled by the SPOT WELD TIMER dial.
E. Continuous Position - With the toggle switch in the CONTINUOUS (center) position, the welding continues as long as
the Mig gun trigger is depressed.
F. Trigger Lock Position - With the toggle switch in the TRIGGER LOCK (right) position, the welding process begins when
the gun trigger is depressed. Once the welding process has started, the gun trigger may be released without aecting
the welding process. To stop the welding operation, the gun trigger must be depressed a second time. This allows a
continuous weld without having to continuously depress the gun trigger.
Continuous
“ON”
Trigger Latch
“ON”
Spot “ON”
Spot Time
Preow
Time
Postow Time
Burnback
Time
SECTION 4 OPERATION