iWeld SW-1250, User Manual

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EN
5-2. SAW
1) Connect the input cable of the machine.
2) Connect the earth cable.
3) Place the work mode selector switch in “SAW”.
4) Use the positive output cable to connect the “+” of the machine and the welding tractor.
5) Use the negative output cable to connect the “-”of the machine to the workpiece to be
welded.
6) As required, connect the control cable between the machine and the control box.
7) As required, choose a proper control mode, “Remote” or “Local”.
8) Fix the welding specifications as per the workpiece, place the striking current and thrust cur-
rent knob to a proper position.
9) Connect the input 3-phase cable with the air switch on the power distribution panel or cabi-
net and then turn the switch on.
10) Adjust the welding current and arc voltage knob, preset the welding current and arc volt-
age and then start welding.
Note : When replacing the welding cable and the tip, be sure to power off the machine.
The output characteristic curve of the machine is as shown in Figure 6 . below.
A
B
C
M
N
90V
21V
0
Output voltage (V)
Output current (A)
U=20+0.04I
D
Fall characteristic
Figure 6 .
Output Characteristics of SW-1250
Note : M-A-B-C is the output static characteristic curve while N-B load curve.
· Use the current adjustment knob to adjust the welding current, i.e. adjust the distance be-
tween AB section on the output characteristic curve and the vertical axis. AB section curve is
the constant current output characteristic section of the machine and its adjustment scope is
from the min. current to the rated welding current of the machine.
· Use the thrust current adjustment knob to adjust the thrust current and the corresponding
output characteristic curve is DC section; adjust the thrust potentiometer, i.e. change the slope
of SC section (as shown by the beeline taking Point B as axis). In MMA, trust current adjustment
scope: O~150A; in SAW thrust current adjustment scope: O~450A.
· Use the striking current adjustment knob to adjust the transient additional current in striking.
With reasonable striking, the current may effectively prevent sticking to the welding rod and
thus the striking success rate can be improved. The adjustment scope of this current is: 80±10A~
80+I/4 (I is the rated current of the machine).
· Welding line formation and specifications adjustment
· Welding line formation is closely related to welding specifications. Generally, there are the fol-
lowing rules:
· If the specifications lie in the constant current area (thrust current=0), there will be shallow
welding, large excess welding metal and narrow welding line;
· If the specifications lie in the slow fall area (thrust current=0), there will be deep welding, small
excess welding metal and narrow welding line;
· When the welding current is adjusted up, the welding depth and welding line will increase.
· When the thrust current is adjusted up, the welding depth will increase while the excess weld-
ing metal will decrease.
· When the SAW welding voltage is adjusted up, the welding depth will decrease, the welding
line will increase while the excess welding metal will decrease.
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