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10. OPERATION (continued)
10.1.8 AC balance Setup ( )
By pressing the AC BALANCE key (
Ԟ
) when the initial conditions, main conditions or crater
filler conditions are being selected, the left-upper LED lights up and the set point is displayed
on the right-side digital meter. (At this time, all unit LEDs are going out.) In this condition, it is
possible to set up the intensity of arc cleaning action indispensable to AC TIG welding of
aluminum or the like with the parameter adjusting knob (
ԛ
). The setup range is 0 to
r
20.
By pressing the AC BALANCE key again or parameter selection key (
Ԛ
), the parameter item
in which the parameter was adjusted to the value of one step ago is selected.
For the AC balance set point, with “0” as standard, the AC balance becomes small in the
minus direction, whose set point is “-20” max., and in the plus direction, the AC balance
becomes large, whose set point is “20” max.
The relationship between the AC balance setup and welded results & electrode consumption
extent or degree is as shown in the table below.
“EN” refers to the period in which the base metal is positive in polarity (+) and the torch is
negative in polarity (-), and “EP” refers to the period in which the base metal is negative in
polarity (-) and the torch is positive in polarity (+).
By adjusting this AC balance, the EP ratio changes by 1% in relation to the manipulated
variable “1”. The EP ratio standard value (when the center position is “0”) differs among AC
waveforms, and the maximum and minimum values that can be set up as EP ratio also differ.
The value indicated on the digital meter can also be used as EP ratio in AC balance setup. For
details, see “10.1.17 – Internal Function”.
The AC waveform, standard EP ratio and settable maximum and minimum values are as
shown in the table below.
AC Wave form
Standard Value
㪤㪸㫏㫀㫄㫌㫄㩷㪭㪸㫃㫌㪼
㪤㫀㫅㫀㫄㫌㫄㩷㪭㪸㫃㫌㪼
STANDARD
30%
㪌㪇㩼
㪈㪇㩼
SOFT
30%
㪌㪇㩼
㪈㪇㩼
HARD
20%
㪊㪇㩼
㪌㩼
Minus Direction
㪚㫃㪼㪸㫅㫀㫅㪾㩷㪮㫀㪻㫋㪿㩷㪪㪼㫋㫌㫇
㪧㫃㫌㫊㩷㪛㫀㫉㪼㪺㫋㫀㫆㫅
Small
㪚㫃㪼㪸㫅㫀㫅㪾㩷㫎㫀㪻㫋㪿
㪣㪸㫉㪾㪼
Deep
㪧㪼㫅㪼㫋㫉㪸㫋㫀㫆㫅
㪪㪿㪸㫃㫃㫆㫎
Less
㪜㫃㪼㪺㫋㫉㫆㪻㪼㩷㪺㫆㫅㫊㫌㫄㫇㫋㫀㫆㫅
㪤㫌㪺㪿
Low
㪜㪧㩷㫉㪸㫋㫀㫆
㪟㫀㪾㪿
The EP ratio is such that the current
ratio of EP polarity at one cycle of
alternating current is expressed in
“percent”, which is defined by the
following equation:
Iep
EP ratio=
̆̆̆̆̆̆̆
100%
Ien + Iep
Ien
Iep
㧜
EN(-)
EP( + )