WIA WELDMATIC 270C, Руководство оператора

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12
Operators Manual
Quality
•
Reliability
•
Performance
6 Normal Welding Sequence
Weld Start
Closing the welding gun switch initiates this
sequence of events:
• The gas valve is energised and gas flow
commences and continues for any pre-gas
time set
• The power source contactor function
is initiated. Welding voltage is applied
between the work piece and the
consumable wire
• The wire drive motor is energised
• The wire touches the work piece, and the
arc is established.
Weld End
Releasing the gun switch initiates this
sequence of events:
• The wire drive motor is de-energised, and
is dynamically braked to a stop
• After a short pre-set period, known as
the ‘burn-back’ time, the power source
contactor function is released. This period
ensures that the consumable wire does
not ‘freeze’ in the weld pool
• At the completion of any post-gas time
set, the gas valve is de-energised and the
flow of shielding gas ceases.
Compression screw
Top roller arms
Fig 5 WF042 Four Roll Drive
Inlet guide
Drive rollers
Feeding the Consumable Wire
At the wirefeeder, release the compression
screw and rotate the top roller arms to
the open position. The end of the welding
wire can now be passed through the inlet
guide, over the first lower roller, through the
intermediate guide, over the second lower
roller and into the output wire guide tube.
Check that the drive roll grooves are correct
for the wire in use. The appropriate size is
stamped on the visible side of the installed
rollers. Check also that the correct size
contact tip is fitted at the gun end. Feed
roller and tip details are shown in Section 11
of this manual.
Return the top roller arms to the closed
position and adjust the compression screw
to provide sufficient clamping of the drive
rollers to achieve constant wirefeed. Do not
over tighten.
With the equipment energised, operate the
gun switch to feed wire through the gun cable.