5.4 Precautions on Using Extension Cable
5-2
HW0480311
HW0480311
Fig. 10 Direction of Welding and Torch Angle
5.4
Precautions on Using Extension Cable
When an extension cable is used, actual output between the torch and the base metal
decreases because of voltage drop in the cable. To prevent this, set the command value of
welding voltage adjustment higher than the target voltage value to compensate for the output
voltage drop. " Fig. 11 Reference for Voltage Drop along Extension Cable " shows a
reference for the voltage drop along an extension cable.
Use the one-class thicker extension cable to keep stable welding voltage.
Fig. 11 Reference for Voltage Drop
along Extension Cable
This graph indicates the relationship
between voltage drop and welding
current when an extension cable of 60
mm
2
is used. If extension cables are
used for both ways, the voltage drop
becomes twice as much as the value
indicated in this graph.
This graph indicates the relationship
between voltage drop and welding
current when an extension cable of 80
mm
2
is used. If extension cables are
used for both ways, the voltage drop is
twice as much as the value indicated in
this graph.
• If an extension cable is used for pulse welding, the response for the pulse waveform con-
trol may be delayed, which may prevent the spatter-less pulse welding. Use a cable as
short as possible for high quality welding.
• In order to compensate for the voltage drop due to extension cables, etc., perform auto-
matic correction by the calibration of the external resistance value which is described in "
14 Calibration for External Resistance ".
4
2
0
100
200
300
500
25m
20m
15m
10m
4
2
0
100
200
300
500
25m
20m
15m
10m
Voltage
drop (V)
Voltage
drop (V)
Welding current (A)
Welding current (A)
Extension cable length
(one way)
Extension cable length
(one way)
SUPPLE
-MENT
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