LOKERMANN GRAND PIPE 270 MULTI, User Manual, Page: 10 / 16

The start current and crater current can be pre-set. This function can compensate the possible crater
that appears at the beginning and end of the welding. Thus, 4T is suitable for the welding of medium
thickness plates.
Pulsed TIG long welding
（ 4T ） ：
Introduction ：
0 ： Press and hold the gun switch, Electromagnetic gas valve is turned on. The
shielding gas starts to flow;
0 〜 t1 ： Pre flow time, adjustment range of pre flow time :0.0~2.0S;
t1 ： Striking success, adjustment range of start current: 5~270A;
t2 ： Loosen the gun switch, the output current slopes up from start current; if the
output pulse function is turned on, the output current is pulsed;
t2 〜 t3 ： Output current slopes up to the setting current value; adjustment range of up slope
time 0~10.0S ;
t3 〜 t4 ： Welding process. During this period, the gun switch is loosen;
Note: If the output pulse function is turned on, the output current is pulsed. If the output pulse function
is turned off, the output current is the welding current (Iw);
t4 ： Repress down the gun switch, the output current slopes down to crater current; if the
output pulse function is turned on, the slope down current is pulsed;
t4 〜 t5 ： Down slope time, adjustment rang of down slope time: 0~10.0S;
t5 〜 t6 ： Crater current holds time; adjustment range of crater current: 5~270A;
t6 ： Loosen the gun switch, stop arc, and keep on argon flowing;
t6 〜 t7 ： Post flow time, adjustment range of post flow time: 0.0 〜 10.0S;
t7 ： Electromagnetic valve is closed and stop argon flowing. Welding is finished.
4.3
Argon Arc
Welding
Operation
4.3.1
TIG welding
（ 4T operation ）
t
（
s
）
0
I
（
A
）
Loosen the switch
t1 t5
t7
Striking success
Stop arc
t3 t4
Base current setting value
t2 t6
Loosen the
switch
Repress down the
switch
Start current
Crater
current
Welding current (peak
current) setting value
Press and hold the welding
gun switch
4.3.2
TIG welding
(2T operation)
t
（
s
）
0
I
（
A
）
Loosen the welding
gun switch
Press and hold the welding
gun switch
t1 t5
Striking success
Stop arc
t3 t4
Base current setting value
t2
Welding current (peak
current) setting value
5A