Bosch Rexroth PST 6 Serie Betriebsanleitung Seite 371

1070087088 / 08 | PST 6xxEx
WC start time
Start
WC
WLD
Start
WC
WLD
Fig. 74: WC period in dependence on signal "Start"
The programmed WC period is also executed in case of start simu­
lation (BOS)!
The time when "Weld complete contact" is to be output can be parame­
trized, in relation to the end of HLD, in the range of +/-50 cycles (restric­
tion: the output of WC is possible 1 cycle after the start of HLD at the
earliest).
As a result, the start time of WC can be pulled into the HLD as well as
delayed.
WC
WLD
Fig. 75: Shifting the WC start time
Example: "high‐speed robot communication"
If "Weld complete contact" is used as command for positioning on the
next spot, the bringing forward of the WC start time may compensate
constant response times (triggered by the signal processing in the ro­
bot, drive or PLC area). The consequence is shorter cycle times.
WC output too early
Damage to the system is possible by positioning movement with
closed welding gun!
" Therefore, make sure that the electrodes are open when you start
the robot drives!
Bosch Rexroth AG
I/O signals for machine applications
"Start" is not active anymore:
progr. WC period is executed.
progr. period
HLD
"Start" is still active:
neg. edge resets WC.
HLD
WC start time
0
< 0 > 0
HLD
NOTICE
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