Eaton XC200 Series, User Manual

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CPU operation
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Switch-off behaviour
Switch-off (operating mode selector switch: Run r Stop) leads to
an interruption of the program run the end of the cycle. Running
of the program is ended immediately with a voltage dip (switching
via the PFI signal). The outputs are switched off at the same time.
When the supply voltage returns, the controller carries out a
restart (see section “Startup behaviour”).
Start behaviour
The start behaviour of the controller depends on:
• the position of the local operating mode selector switch
• the parameter settings for start behaviour that were set in the
programming system.
(With the CPU version “XV” (visualisation CPU), it is basically
possible to operate the system from the system menu in the
display).
The position of the operating mode switch determines whether the
operating states changes from “Stop” to“Run”.This change cant
be forced by a corresponding choice within the programming
system.
When a program starts, a check is made whether the configured
inputs and outputs match those that are actually present. A check
is also made whether the module that was parameterized is
physically present, or a different module. A module that is not
present will not have any effect on the start of the application
program, but if the module is a different type, the start will be
prevented.
When the application program starts, a distinction is made
between (see also the following sections):
• Cold start
• Warm start
Stop behaviour
The processing of the application program always halts at the end
of a program cycle.
Cold start
A cold start is initiated during the initial start, after loading a
program to the PLC and after every “Cold reset”. During this start,
all the program variables are set to their initialisation values and
the program is started.
Warm start
All further starts of the loaded program as well as after “Warm
resets” are warm starts. The variables that were declared with
“RETAIN” retain their values, the other variables are set to their
initialisation values and program is started.
Test and commissioning
The PLC supports the following test and commissioning features:
• Breakpoint/single-step mode
• Single cycle mode
• Forcing
• Online modification
• Status indication (Power Flow).
Breakpoint/single-step mode
Breakpoints can be set within the application program. If an
instruction has a breakpoint attached, then the program will halt at
this point. The following instructions can be executed in single-step
mode. The cycle-time monitoring is deactivated.
Single-cycle mode
In single-cycle operation, one program cycle is performed in real
time. The outputs are enabled during the cycle. At the end of the
cycle, the output states are cancelled and the outputs are switched
off. The cycle-time monitoring is active.
Forcing
All the variables in an application program can be forced to a given
setting. If variables for physical outputs of the local I/Os are forced,
they will only be connected through to the peripherals in the
“Run” state.
Status indication, easySoft-CoDeSys
• The signal state of the physical, Boolean inputs are displayed in
“Start” and “Stop” mode.
• The signal state of the physical, Boolean outputs are only
displayed in “Start” (RUN) mode.
• The display for a low signal is displayed with “FALSE” and has
a black background.
• The display for a high signal is displayed with “TRUE” and has
a blue background.
• All other variables are only displayed in “Start” mode with the
current respective variable value.
i
Caution!
At this moment any outputs set will remain set!