6
Short/Spray Arc Welding
When setting a schedule number 5 to 8, the feeder control and power source is automatically set for short/
spray welding. The operator has full control over the slope and inductance of the power source. The IPM
window will display the preset wire feed speed in inches per minute. The VOLTS window will display arc
voltage and can be adjusted to any arc voltage needed for a good welding condition by using the Inc/Dec
key under the VOLTS window. The feeder control will automatically adjust the power source to maintain the
arc voltage set in the VOLTS window. There is no synergic relationship present in the short/spray arc sched-
ules.
Arc Start (Servo) Settings
Each schedule on each torch can have its own starting characteristic for any given weld parameter. The arc
start level must be set during welding. Choose desired schedule number and set a good welding condition.
If the arc starting is less than desirable it can be adjusted as follows:
Depress the Purge and Schedule Select key simultaneously while making a weld (two man operation).
The VOLTS window will display a number between 0 and 200 (95 is the typical setting). Using the Inc/Dec
key below the VOLTS window, reduce the number shown to give a hotter arc start or increase the number
for a colder arc start. Your setting will be saved to that schedule and will be recalled when you select that
schedule again. Changes in wire feed speed and/or voltage might necessitate readjusting the voltage servo
to optimize starting characteristics. Repeat this procedure for other welding schedules being used.
Motor Servo Setting
You can adjust the feed motor response by presetting the motor speed servo. Release the pressure roll and
pull the torch switch while depressing the Purge and Schedule Select key simultaneously. Change the
number (110 is standard) in the IPM window using the Inc/Dec key to a lower value if a faster motor
acceleration is needed or a higher number for a slower motor acceleration.
Warning - The motor response adjustment will be in effect for ALL schedules and BOTH
torches. The servo number set in the IPM window can be set exactly for the schedule
being used and wire feed speed preset but switching to a different schedule having a
different wire feed speed setting will cause the servo number in the IPM window to vary
slightly. This is normal and should have little affect on welding performance.
Power Source Changes
The standard SVI-450i power source has been modified to achieve the performance requested by Bombar-
dier, Inc. Pulse arc capability has been added and the V/A slope has been adjusted to Flat Slope = 3 V/100
Amps, Medium Slope = 4.5 V/100 Amps and Steep Slope = 6 V/100 Amps. A separate part number and
special drawings have been established for this machine which include a unique calibration procedure. Do
not attempt to use a standard SVI-450i power source as a substitute.
Additional Features
Displaying Welding Parameters
The feeder will display the actual welding conditions (IPM and Volts) during welding and will retain these
values for 2-1/2 seconds after welding. After 2-1/2 seconds the display will revert to the preset parameters.
To view the last welding condition used, bump the torch trigger. The welding conditions will be displayed.
Displaying Schedule Numbers
The schedules selected for each torch can be viewed by depressing the Schedule Select key on the feeder
control or depress and hold the torch trigger (without welding).