ESAB Origo Arc 410c, Руководство по обслуживанию

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A voltage measurement signal proportional to the welding current is transmitted to the LM11/1 board
located on the A12 panel via the RC filter composed of RA
1
and CA
1
elements. The welding voltage
measurement signal is carried to the LM11/1 board via the filter composed of RV
1
and CV
1
elements.
Circuit reducing the current required for activating the device
Circuit reducing the current value required for activating the device switches on the K1 main contactor
only after the capacitor batteries in the chopper have been charged. This circuit is a typical Schmitt
trigger made on the A3a comparator, controlled by the voltage of a charging capacitors battery and
performing the switching on of the K1 contactor with delay in relation to the moment of switching on
the source via the Q01 switch. Activation of this circuit after the battery has been charged is signalled
by the V
12
diode.
Steering voltage source
The steering voltage is created by rectifying the alternating voltage of 42V via the bridge rectifier made
on diodes V
42
, V
43
, V
44
, V
45
, and then filtered by C
106
and C
107
capacitors. The voltage is connected in
parallel to output terminals of the source via the R2 resistor, which serves as a detector of the level of
contact of the electrode and the welded material as well as the detector of the signal sent by the N02
transmitter. In the TIG method, the steering voltage is switched on by the K2 transmitter when the
button on the welding torch is pressed, while in MMA and AG methods, it is switched on permanently,
providing the source resting voltage of approx. 56V.