Fronius DeltaSpot G2, Operating Instructions And Spare Parts List

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Example:
(1) Welding current axis
(2) Time axis
Longest current time = 500 ms
/shortest welding cycle time = 2500 ms
DC_Diodes = 500 ms/2500 ms x 100 % =
20 %
Calculating the maximum transformer duty cycle
- Since the transformer has a higher heat capacity, the maximum permitted duty
cycle is calculated on the basis of the welding cycle with a maximum integration
time of one minute
DC_Transf = (number of welds x current time for each welding spot/integration time)
x 100 %
Example:
(1) Welding current axis
(2) Time axis
Number of welds = 1 x 10 spots
current time per welding spot = 600 ms
integration time = 60 s
DC_Transf = (1x10 spots x 600 ms/60000
ms) x 100 % = 10 %
IMPORTANT! The transformer user documentation will be supplied with your system
or can be requested from Fronius Technical Support.
Calculating the maximum permitted welding currents for diodes (I_max_Diodes) and
transformer (I_max_Transf):
- Find the transformer load diagram
- Mark a vertical line on the diagram for the diode duty cycle (DC_Diodes)
- Search for a diode characteristic that corresponds to the longest current time for
each welding spot and read off the current at the intersection with the vertical line
for the diode duty cycle -> I_max_Diodes
- Draw a vertical line on the diagram for the transformer duty cycle (DC_Transf)
- Read off the current at the intersection with the vertical line for the transformer
duty cycle -> I_max_Transf
Calculating the maximum permitted inverter current
Calculating the maximum semiconductor duty cycle
- Due to the limited heat capacity of the semiconductors, the maximum permitted
duty cycle is determined using the "current time to welding cycle time" period.
- If the application uses current times or welding cycle times of different lengths, al-
ways use the longest current time and shortest welding cycle time
DC_Inverter = current time/welding cycle time x 100 %
Example:
500 ms
2500 ms
(1)
(2)
2
10 spots
60 s
(1)
(2)
600 ms
3
4