Notes on Configuration
S7-GRAPH for S7 300/400 Programming Sequential Control Systems
14-6
C79000-G7076-C526-01
Representing the Mode in the Sequencer
If, for example, a selector switch on the control panel supplies the signals
automatic, inching and manual as individual single signals, only relatively simple
logic is required to derive the mode signals for the sequencers and for the
underlying drives of the units as shown in principle in the following diagram.
FB unit group n
Automatic
Manual
SW_MAN
SW_AUTO
SW_TAP
Seq_Auto
Seq_Inch
Seq_Man
Autom.
Inching
Manual
Unit_Auto
Unit_Hand
Process
enable
. 1
Mode
selector
FB unit group 1
Automatic
manual
SW_MAN
SW_AUTO
SW_TAP
FB sequencer n
Mode setting
FB sequencer 1
&
&
&
&
. 1
The modes selected at the console are passed on to the sequencers when
Process_enabled is active. If Process_enabled is not set, the modes of the
sequencers are switched to SW_MAN and step enabling is suppressed.
In the automatic or inching modes, the automatic mode is set for the unit functions.
The manual mode is passed on directly. If Process_enabled is not set, both modes
are canceled and movements stopped. The functions of the unit groups are
represented in an FB created with LAD/FBD or STL.