Danfoss MCO 305 Design Manual page 72

MCO 305 Design Guide
Autostart
In order to support the use of the controller in "stand-alone" or "turnkey" applications (i.e. without user
input), the controller can be configured so that an APOSS program is started automatically when the con-
troller is powered on. Typically, in these types of applications, the controller must also never be "stopped".
So the controller can also be configured to restart an APOSS program in the event that the executing
program terminates.
The first part of this mechanism is the "Autostart program". The Autostart program (if one is defined) is
normally always started automatically when the controller is powered on. If no Autostart program has been
defined, then no program is started when the controller is powered on. Note that when the controller is
powered on, it will run various self-test checks. If any of these fail, then the controller will not attempt to
start the Autostart program.
The second part of the Autostart mechanism is the "Restart program". With some exceptions, the Restart
program is started automatically when the currently executing program terminates. In particular, this
includes the termination of the Autostart program.
NB!:
If the Autostart program, Restart program, or any other program is aborted by the user, then the
Autostart mechanism will be deactivated. The controller will not automatically start the Autostart
program or any Restart program again until the controller is powered off and on.
NB!:
Note that a program designated as an Autostart program can always be manually started by the
user. However, in this case, the program will execute as a normal program, not as an Autostart
program, and no Restart program will be started when the program terminates.
Autostart program
The controller determines the Autostart program as follows:
1. If a program has been explicitly marked as the "Autostart program" (see below), then this program
will be started when the controller is powered on.
2. Otherwise, if par. 33-5* I_Function_n_13 or 14 is set to a digital input pin, then 33-5*
I_Function_n_15 will determine the program number of the Autostart program. The controller will
wait until the input pin is activated and the Autostart program will then be started.
Note that the pin may already be activated when the controller is powered on. These parameters
are designed to be used when the Autostart program is being selected by some external source
(such as a PLC).
3. Otherwise, there is no Autostart program.
Any saved program can be designated as the Autostart program by selecting it and clicking → Autostart on.
The Autostart program will be marked with a
cleared again simply by selecting the program and clicking → Autostart off. Only one program at a time can
be designated as the Autostart program. So if a second program is chosen as the Autostart program, then
the Autostart designation is cleared from the previous program.
One of the main purposes of an Autostart program is to select which of multiple programs is to be executed
in applications that require different programs in different situations. The Autostart program will identify
(usually based either on configuration parameters or on digital input settings) which program is to be exe-
cuted. The Autostart program then designates that program as the Restart program and terminates. The
controller will then automatically start the designated program.
NB!:
The Start program mechanism (33-5* I_Function_n_13 or 14) does not function properly in some
Motion Controllers prior to MCO 5.00. If this affects the application, then please contact your
supplier for updated firmware.
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__ PC Software Interface __
in the Autostart column. The Autostart designation can be
®
MG.33.L5.02 – VLT is a registered Danfoss trademark