User Manual

Control concept
Control concept and control blocks
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Function Inputs Description AI_RED AO_RED BI_RED BO_RED MI_RED MO_RED
Stop transmission
of input signal
OoServ Out of service
DefVal Default value
• • •
Priority mechanism PrioArr Priority array
• • •
Local override Ovrr Override
• • •
OvrrVal Override value
• • •
Alarm value
monitoring
- Limits
- Reference values
- Monitoring
periods
EnAlm Alarm enable
HiLm Upper limit
LoLm Lower limit
Nz Neutral zone
RefVal(s) Reference value
TiMonOn Monit. time
switch-on
TiMonOff Monit. time
switch-off
TiMonDvn Monit. time
deviation
Switching delays DlyOn Switch-on delay
DlyOff Switch-off delay
TbTiDly Table for time
delay
Switching action
- Normal
- Release command
- Trigger
SwiKind Switch kind
• • •
Function Outputs Description AI_RED AO_RED BI_RED BO_RED MI_RED MO_RED
Feedback
monitoring
PrVal Present value
• • • • • •
FbVal Feedback value
Reliability
monitoring
Rlb Reliability
• • • • • •
Fault monitoring Dstb Fault
• • • • • •
Status monitoring TraSta Transitional state
• • •
Priority monitoring SftyActv Safety priority
Active
• • •
CritActv Critical active
• • •
PgmActv Program active
• • •
PrPrio Present priority
• • •
Priority mechanism
Within the Desigo PX system, the BACnet priority mechanism is used for the I/O output blocks and in the
value blocks. This priority mechanism provides a series of prioritized levels at which intervention is
possible, for use with the control functions in HVAC plant and the associated components.
The following priority levels are available with blocks AO, BO, MO (and blocks AO_RED, BO_RED, MO_RED)
and AVAL, BVAL and MVAL.