Fronius TPS 270i C User Manual

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(7) Example of pre-set arc-force dynamic where characteristic (4) is selected
(8) Example of pre-set arc-force dynamic where characteristic (5) or (6) is selected
I-constant (constant welding current)
- If the "I-constant" parameter is set, the welding current will be kept constant, irrespec-
tive of the welding voltage. This results in a vertical characteristic (4).
- The "I-constant" parameter is particularly suitable for rutile electrodes and basic elec-
trodes.
0.1 - 20.0 A/V (drooping characteristic with adjustable slope)
- Parameter "0.1 - 20" is used to set a drooping characteristic (5). The setting range ex-
tends from 0.1 A / V (very steep) to 20 A / V (very flat).
- Setting a flat characteristic (5) is only advisable for cellulose electrodes.
P-constant (constant welding power)
- If the "P-constant" parameter is set, the welding power is kept constant, irrespective
of the welding voltage and welding current. This results in a hyperbolic characteristic
(6).
- The "P-constant" parameter is particularly suitable for cellulose electrodes, as well as
for arc air gouging.
- For arc air gouging, set the arc-force dynamic to "100".
(1) Load line for rod electrode
(2) Load line for rod electrode where
arc length is increased
(3) Load line for rod electrode where
arc length is reduced
(4) Characteristic where "I-constant"
parameter is selected (constant
welding current)
(5) Characteristic where "0.1 - 20" pa-
rameter is selected (drooping cha-
racteristic with adjustable slope)
(6) Characteristic where "P-constant"
parameter is selected (constant
welding power)
(8) Example of pre-set arc-force dynamic where characteristic (5) or (6) is selected
(9) Possible change in the current where characteristic (5) or (6) is selected, as a func-
tion of the welding voltage (arc length)
(a) Operating point where arc length is long
(b) Operating point where welding current I
H
is set
(c) Operating point where arc length is short
The characteristics (4), (5) and (6) shown here apply when using a rod electrode whose
characteristic corresponds - at a given arc length - to the load line (1).
Depending on what welding current (I) has been set, the point of intersection (operating
point) of characteristics (4), (5) and (6) will be displaced along the load line (1). The oper-
ating point provides information on the actual welding voltage and the actual welding cur-
rent.
Where the welding current (I
H
) is permanently set, the operating point may migrate along
the characteristics (4), (5) and (6) according to the welding voltage at a given moment. The
welding voltage U is dependent upon the arc length.
10
20
30
40
50
60
U (V)
004003001 200
I (A)
I
H
+ DynamikI
H
- 50 %
(8)
(2)
(1)
(3)
(7)
(c)
(c)
(b)
(a)
(a)
(6)
(5)
(4)

Fronius TPS 270i C Specifications

General

Brand	Fronius
Model	TPS 270i C
Category	Welding System
Language	English