Eaton Vickers SMC20, Техническая поддержка продукции

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b) Conditional Jump. Defined by a
logic equation evaluated after the
Exit Conditions are satisfied. For
example, from the Jump Event
Condition screen: ––> EDIT and
ENTER.
↑
QUIT F1
1 START DEL F2
2 [10#[13] ] <INS F3
END EQ
↓
SAVE F4
Note that not all of the above four
categories have to have entries in every
segment. It is possible to program a
segment that does not move at all, but
only checks logic equation(s) and it is
possible to program a simple move with
no special Entry or Exit Conditions. A
simple move may use several of the axis
default values and thus require not
much more than an Absolute or Relative
Target Position.
There are two additional things that can
be, but do not have to be used in a
segment:
5. Gains
A maximum of three gains can be
defined. These override selected
PID gains to change axis stability
FOR THIS SEGMENT ONLY. A
possible use would be with an axis
that has a large change in inertia for
a few segments of the profile.
6. Variables
Refer to Programming Reference
Manual.
Sequence of Execution
When the SMC20 executes a segment,
it does not do all of the operations at the
same time. There is an order, or
sequence, in which execution occurs. It
is important to keep this order in mind as
results different than otherwise expected
can occur.
1. If a Dwell Time has been
programmed as part of the Input
Conditions, it will start timing and
completely time out before anything
else occurs.
2. Next, any Input Events that are part
of the Input Conditions are executed
– such as reading inputs or turning
‘On’ or ‘Off’ any outputs.
3. Next, Motion Parameters and Motion
Profile Data are executed – all at the
same time. This includes reading
any variables required, setting new
values of gains for that segment and
computing and loading all targets.
4. Next, Output Events that are part of
the Output Conditions – such as
turning Outputs ‘On’ or ‘Off’ and
setting internal flags –– are executed.
5. Next, any Conditional Jumps that are
part of the Output Conditions are
executed.
6. And finally, any Jump Conditions are
executed –– direct jumps are those
with no conditions attached, such as
jumping directly to a particular
segment number no matter what else
is happening.
Note, that if gains or variables are
updated at any time prior to step 3, they
will take effect in the current segment –
otherwise they will take effect in the
following segment.
Program Mode
The PRG mode is used to enter new
segments, edit previously entered
segments AND to enter changes to
parameters that will apply ONLY to
segments. The parameters changed
are those entered in the CFG mode
(See Introduction to Programming
section, page ##). These parameters
can only be changed in a downward
direction in the PRG mode. The PRG
mode is entered by pressing the ‘PRG’
key on the pendent.