Chapter 9
247
Logic programming – Function blocks
9.12.3 Press automatic
Function block diagram
General description
The Press automatic function block is used in connection with press applications in
which the workpieces are moved automatically to and from the press, but where
occasionally access to the press is required, for example to change a tool.
To this purpose the function block can generate a stop signal for the press (i.e. the
Enable output changes to Low) in a position in which the tool can be changed easily
(e.g. in the top position), when a stop has been requested before.
Parameters of the function block
Parameter Possible values
Restart interlock after stop condition With
Without
Stop request When Start/Release input is Low
When Stop input is High
Upstroke input With
Without
Release 2 (start) input With
Without
Min. restart pulse time 100 ms
350 ms
Ensure that the transitions of the signals for restarting fulfill the requirements of
the safety standards and regulations!
In case of a short-circuit to High (to 24 V DC) at a physical input, the evaluated signal
can have a pulse when the signal is reset due to the short-circuit detection. If such a
pulse can result in a dangerous state in the machine, the following points have to be
observed:
Ensure protected cable laying for the signal line (due to cross-circuiting to other
signal lines).
No short-circuit detection, i.e. do not reference to test outputs.
Figure 232:
Function block diagram for
the Press automatic function
block
Table 111:
Parameters of the Press
automatic function block
ATTENTION
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