Explanation Of The Term "Duty Cycle" In Single-Phase Operation - Fronius TransSteel 2700c MultiProzess Operating Instructions Manual

Grid voltage
Fuse rating
240 V
20 A
240 V
30 A
D.C.
*
The welding current data applies at an ambient temperature of 40 °C (104 °F).
At a grid voltage of 240 V and a fuse rating of 30 A, the maximum value of 220 A
is possible for MIG/MAG welding with a duty cycle of 40% for example.
In single-phase operation, a safety cut-out prevents the fuse from tripping at
higher welding powers. The safety cut-out is active at fuse ratings of 15 A, 16 A
and 20 A and determines the possible welding duration, without the fuse being
tripped. If the precalculated weld time is exceeded, thus causing the welding cur-
rent to switch off, the service code "toF" is displayed. A countdown immediately
appears next to the "toF" indicator, which shows the remaining time until the
power source is ready for welding again. After this time, the message disappears,
and the power source is ready for operation again.
At a fuse rating of 30 A, the temperature monitoring for the power source en-
sures the welding current is promptly switched off. A service code from "to1" to
"to7" is displayed. Detailed information on the service codes "to1" to "to7" can be
found in the "Troubleshooting" chapter under "Displayed service codes". If there
is no fault or the cooling components are not dirty, then the device will be ready
for welding again after an appropriate welding pause.
Explanation of For single-phase operation, the "Technical Data" chapter specifies duty cycle val-
the Term "Duty
ues as a function of the fuse rating and the welding current. Although the per-
Cycle" in Single- centages of these duty cycle values are also based on the ten-minute cycle ex-
Phase Operation plained in the "Technical Data" chapter for general duty cycles, the cooling phase
of the fuse, however, is calculated at approx. 60 s only. Afterwards, the power
source is once again ready for use.
Due to technical standards, in single-phase operation, the duty cycle is only spe-
cified up to the end (switch off) of the first welding cycle. If the relationship to
the ten-minute cycle normally used when specifying the duty cycle was also es-
tablished with respect to the cooling phases, in practice there would be longer
welding phases than those stated. The values are actually based on cooling
phases of approx. 60 s only, after which the power source is ready for further use.
48
Welding process
MIG/MAG
Rod electrode
TIG
MIG/MAG
Rod electrode
TIG
= Duty cycle
The 100% values relate to welding with no time limits and without cooling
breaks.
D.C. Welding current limitation
[%] [A]
40 200
100 * 160
40 180
100 * 140
35 260
100 * 180
40 220
100 * 170
40 180
100 * 140
35 260
100 * 180