Lincoln Electric IDEALARC SP-250 Service Manual page 27

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10. If SPOT timing mode required.
a. Press SPOT key.
b. Press CENTER UP or DOWN ARROW keys to
select SPOT ON TIME required.
c. Press SPOT key to return to previous display.
d. Go to Step 12.
11. If STITCH timing mode required.
a. Press STITCH key.
b. Press CENTER UP and DOWN ARROW keys
to select STITCH ON time required.
c. Press RIGHT UP or DOWN ARROW keys to
select STITCH OFF time required.
d. Press STITCH key to return to previous dis-
play.
e. Go to Step 12.
12. Inch the electrode through the gun and cable
13. Cut the electrode within approximately 3/8" of the
end of the contact tip (3/4" for Outershield).
NOTE: When the trigger is pulled, the wire feeder
feeds wire at low speed regardless of the set wire feed
speed until the welding arc starts or 2 seconds has
elapsed. This feature enhances starting and makes it
easier to set the stick out. The two-second limit per-
mits high speed loading of the gun and cable. To
change Run-In Mode, see changing Run-In Mode sec-
tion.
14. If welding gas is to be used, turn on the gas supply
and set the required flow rate (typically 25-35
CFH/12-16 l/min.).
NOTE: When using an Innershield electrode, the gas
nozzle may be removed from the insulation on the end
of the gun. This will give improved visibility and elimi-
nate the possibility of the gas nozzle overheating.
15. Connect work clamp to metal to be welded. Work
clamp must make good electrical contact to the
WARNING
work. The work must be grounded.
WARNING: WHEN USING
PROCESS, IT IS NECESSARY TO USE CORRECT
EYE, HEAD, AND BODY PROTECTION.
____________________________________
16. Position electrode over joint. End of electrode may
be lightly touching the work.
17. Lower welding helmet, close gun trigger, and begin
welding. Hold the gun so the contact tip to work
OPERATION
18. To stop welding, release the gun trigger and then
19. When no more welding is to be done, close valve
20. Turn the ON/OFF POWER SWITCH to OFF.
USING THE 4-STEP INTERLOCK FUNCTION IN
AUTO MODE
When the 4-Step Interlock function is not activated, the
trigger functions in the normal mode so that welding
happens only when the trigger is closed.
When the 4-Step Interlock function is activated, it
functions as follows:
When the arc is struck, the gun trigger may be
released.
stopped by either of these two methods:
1) The arc is extinguished by manually jerking the
2) The gun trigger is closed and then released at the
The 4-step trigger feature does not function when
using SPOT or STITCH timed welding modes.
MAKING A SPOT WELD IN AUTO MODE
Arc spot plug welds are used when continuous welds
are not needed or to hold thin sheet metal together
prior to stitch welding or continuous welding. Arc spot
plug welds are made by using a punch to make a 3/16
AN OPEN ARC inch diameter hole in the top sheet and arc welding
through the hole into the back sheet.
To make an arc spot plug weld
1. Punch 3/16" hole in top sheet.
2. Set the procedure for the metal thickness to be
IDEALARC SP-250
distance is about 3/8 inch (3/4" for Outershield).
pull the gun away from the work after the arc goes
out.
on gas cylinder (if used). Momentarily operate gun
trigger to release gas pressure.
The welding continues until welding is
gun away from the work.
end of the weld. This action returns the trigger
function to the normal mode so the weld stops
when the trigger is released. Releasing the trigger
reinstates the trigger interlock function for the next
weld. This is the preferred Interlock mode
because it provides better control at the end of the
weld and allows automatic burnback to prevent
excessive wire feed speed overrun.
welded.
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