Siemens SIPART DR22 Manual page 38

1 Technical Description
1.5 Functional description of the structure switches
1.5.3 Digital input signal processing
At S47 = 0 static switching takes place due to the logic function RC = Int∧CB. In the case of
the preset to Int (Internal LED (1) off) you can switch statically with CB between controller
values and computer values (command and manipulated variables). The computer standby CB
is displayed negated by the C-LED (3) (C = CB, CB = 1 = C LED off). The computer standby of
the controller is signaled negated as a message signal RB = Int. The computer mode is also
signaled negated as a message signal RC = Int∧CB .
At S47 = 1 static switching with acknowledgement takes place. Every time the computer is re-
covered (CB from 0 ! 1) the internal flip--flop is set to 1 (Internal LED on, C LED off) so that
the computer mode RC = Int∧CB only becomes active after pressing the Internal key (Int=0).
With S49 the Internal/External key can be switched out of function and only internal or external
operation preselected.
The control signal H is generated as an OR-function by the Manual-/Automatic key (9) with sub-
sequent flip-flop (Hi) and the control signal He whereby He can be preset by the SES or the
digital inputs in the way described above.
With the structure switch S64 Automatic-/Manual switching can be blocked in the positions only
Automatic (H = 0) or only Manual (H = 1). The Manual LED (8) always indicates the active
status (see also chapter 1.5.6, page 99).
At S64 = 0 to 2, He is connected statically by both the SES and the digital inputs. At S64 = 3/4
the connection is made dynamically, i.e. every positive edge causes manual-automatic-manual
opeeration switching. Additionally interlocking of He
structure switch S64 = 4.
36
with RC = Int∨CB is canceled at
ES
Manual
SIPART DR22 6DR2210
C79000-G7476-C154-03