User Manual

Control concept
Local control design
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CM110664en_07 71 | 353
wired output [Dstb]. The pump can only be switched on again only after the
fault is eliminated and the alarm message is reset as required.
The following figure shows a local fault-related shutdown related to
superposed plant control. The compound mapped here as an example was
reduced to make is easier to recognize the structure of the local control.
Local fault-related shutdown of the aggregate depicted here as an example is
triggered as follows:
1. A fault is displayed at output [Dstb] when a component valve [Vlv] or pump
[Pu1St] reports a fault (FAULT or OFFNORMAL). The signals revert to
enable safety priority [EnSfty] for block BVAL (1). Fault-related shutdown of
all components is triggered via the state output [SftyActv] (2).
2. You can also impact the safety shutdown of the components via the
compound interface [I1 EnSfty].
The superposed plant control (not displayed here) can access the object
directly via referencing since the block BVAL is mapped on BACnet and has a
priority array [PrioArr]. As a result, plant control can also trigger a shutdown of
the components by commanding the safety priority.
Interlocks
The following figure shows a solution where a fan is only enabled after the
damper is completely open.
PrVal Dstb KickDmp
P15 Pgm P4 Crit
PrVal FbVal Dstb CritActv TraSta
P15 Pgm P4 Crit
P
r
V
a
l
CritActv Dstb
1
4
:
E
n
P
g
m
1
5
:
V
a
l
P
g
m
1
2
.
E
n
C
r
i
t
1
3
.
V
a
l
C
r
i
t
Off
Ort
Ax:OR
CmdVal Cp:BVAL
Or2 Ax.OR
TCtr
PID_CTR
0%
On
Off
EnCrit ValCrit
Pu 1St:
BO
R/sCtl
Data Sink:
Receives Data
The Information is written by a Client with a
certain priority or is read by the Function Unit.