REHM TIGER DIGITAL 180 AC/DC ULTRA, Operating Instructions Manual

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Function description
24
5.2.2 4 cycle operating mode
In the 4 cycle operating mode the need to permanently actuate the trigger is
omitted, enabling the torch to be guided for a longer period without fatigue.
Sequence of the 4 cycle operating mode:

1. cycle
–
operate the torch trigger
The protective gas solenoid valve opens
After the set gas pre-flow time has expired the arc is ignited
The welding current is at the value set for the starting current

2. cycle: Release the torch trigger
The welding current automatically reaches the preset values for I
1
after the
selected slope-up time.

3. cycle: Actuate the torch trigger
The current reduces to the set end crater value at the preselected current slope-
down time.
The welding current flow is at the set end crater value

4. cycle: Release the torch trigger
The arc extinguishes
The inert gas flow is according to the selected gas post-flow value.
Peculiarities:
to the 2nd cycle Actuating the torch trigger a second time during slope-up
of the current extinguishes the arc and the protective gas continues
to flow according to the selected gas post-flow time.
to the 3rd Cycle The arc can be switched off during the slope-down period.
Releasing the torch trigger before reaching the end crater current
extinguishes the arc and the protective gas continues to flow for
the set post flow time.
5.2.3 TIG spot welding
The spot welding mode is recommended for welding with a fixed spot welding
time from 0.01 seconds.
The stationary welding process runs with a fixed spot welding time, unless the
trigger is released prematurely during the welding.
The program runs to the end after expiry of the set spot welding time or after
releasing the torch trigger during the welding.
Torch trigger 1
Gas valve
Welding current
t
t
t
Fig.11 Process for 4 cycle welding