REHM 150 3310, Руководство по эксплуатации

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Description of function
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before starting the welding operation. Whilst holding the button 2 down the value
for the current will be shown on the digital display and using the turn and set
knob the value can be adjusted as required.
3.3.4 The Pulsed Function (Pulse time t2
–
see chapter 3.3.2)
See chapter 3.3.2
3.3.5 Current downslope and manual pulsing
The setting of the current downslope time is performed as described in section
3.1. The downslope time is the time is which the welding current decays in a
linear progression to the crater fill current. In the non-latched torch trigger mode,
(2-step) the downslope time starts when the trigger is released. In the latched
torch trigger mode (4-step), the downslope time starts when the torch button 1 is
depressed during welding. The controlled decay in the current level reduces the
possibility of end crater cracking.
Manual Pulsing:
If the torch trigger is depressed during the downslope then the welding current
jumps back up to the I1 value. This torch operation enables manual pulsing to be
achieved. (see Chapter 3.2.6) The operator controls the heat input during the
pulsing manually by the length of time that has elapsed between the activating of
the torch trigger during the downslope time.
t
t
t
Fig. 3.4: The current cycle diagram when manual pulsing.
3.3.6 Post flow gas time
The setting of the gas post-flow time is performed as described in section 3.1.
The gas post-flow time is the time that elapses after the arc is extinguished
before the shielding gas solenoid closes again. The shielding gas post-flow
protects the weld pool and the tungsten electrode from oxidisation until they have
cooled down. The pre-selected post-flow time is only activated at the end of the
welding cycle. Accidental activation of the torch button does not result in the
activating the post-flow time. This gas management function lowers the shielding
gas consumption.
Solenoid valve
Welding current
Torch trigger 1