Lincoln Electric POWER FEED 25M NNS Operator's Manual page 31

POWER FEED™ 25M NNS
4-Step Trigger
4-step trigger allows the operator to release the trigger once an arc has been established. To end the weld, the trigger is pulled and
then released again.
Two types of 4-Step Trigger are available. Use the set-up menu to select the desired type of operation.
With current interlock, if the arc goes out for more than 0.5 seconds while the trigger is released, the welding process stops and goes
to the idle state.
Without the current interlock, if the arc goes out while the trigger is released, output to the power source remains on and the wire
feeder will continue to feed wire.
Example 1: 4-Step Trigger: Trigger Interlock
The 4-Step trigger can be configured as a trigger interlock. Trigger interlock adds to the welder's comfort when making long welds by
allowing the trigger to be released after an initial trigger pull. Welding stops when the trigger is pulled a second time and then
released, or if the arc is interrupted.
For this sequence,
PREFLOW:
Shielding gas begins to flow immediately when the gun trigger is pulled.
RUN-IN:
After preflow time expires, the power source regulates to the welding output and wire is advanced towards the work
piece at the Run-In WFS. If an arc is not established within 1.5 seconds, the wire feed speed will jump to the
welding wire feed speed.
WELD:
The power source output and the wire feed speed continue at the weld settings. The trigger is released and welding
continues. Welding continues when the trigger is pulled a second time
POSTFLOW:
As soon as the trigger is released for the second time, the power source output and the wire feed speed are turned
OFF. Shielding gas flows until the post flow timer expires.
B 16
OPERATION