User Manual

Control concept
Control concept and control blocks
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Feedback monitoring
[BO, MO]
Monitoring feedback may be based on a data point or a purely internal to the
block based on the feedback time parameter.
● Feedback data point available [FbAddr:] = Address
Monitoring is based on the feedback signals. The delays can be defined
with the time parameters for switch-on [TiMonOn], switch-off [TiMonOff]
and open-circuit [TiMonDvn]. If the feedback signal [FbVal] deviates from
the output value [PrVal], an OFFNORMAL alarm will be triggered (provided
the alarm function is switched on).
● No feedback data point available [FbAddr:] = empty
Based on the feedback time parameter [TiMonOn/TiMonOff], the output
[FbVal] is delayed by [PrVal]. The output [TraSta] signals transition state.
Alarm value monitoring
[AI, AO, AVAL, BI, BVAL, MI, MVAL]
Alarm monitoring is optional and can be enabled using [EnAlm]. Analog limit or
switching values can be monitored depending on the block type. The tolerance
time [TiMonDvn] to trigger a process alarm can be set. Deviations for switch on
and off procedures can be distinguished for switching blocks.
Alarm monitoring can be enabled based on the process or time. You can switch
off frost protection for monitoring in summer e.g..
Reliability monitoring
[AI, AI_RED, AO, AO_RED, AVAL, BI, BI_RED, BO,BO_RED, BVAL, MI, MI_RED,
MO, MO_RED, MVAL]
The blocks monitor the reliability of input and output sources and configuration
errors. A system alarm is generated, e.g., when a source no longer
communicates and the cause is displayed on output [Rlb]. The disturbance
output [Dstb] changes to yes. This output, e.g., can return to the block for the
local disturbance to achieve a more secure position using a higher priority.
Reliability monitoring can be switched off using [OoServ], which may make
sense for defective or faulty hardware.
Reliability monitoring is always active for the RED blocks since no [OaServ] is
available. Superposed control does not distinguish this state and plant safety is
not provided under certain circumstances.
Minimum switching times
[BO, BVAL, MO, MVAL]
The minimum time on [TiOnMin] and the minimum time off [TiOffMin] may be
defined to reduce switching frequency. For a switch on or off command, is
written to [PrioArr] as priority 6 and maintained there during the defined
switching period. No lower priority can change the switching value during this
time frame.
Switch-on and switch-off delay
[BO, BVAL, MO, MVAL]
To delay switch on or off for elements [DlyOn/DlyOff], e.g., to implement a
pump run-on to extract residual heat. For a switch on or off command, the
corresponding switching value is written to [PrioArr] as priority 6 and
maintained there during the defined switching period. No lower priority can
change the switching value during this time frame.
Ramp-up/down time
Runtimes for ramp-up and down
[BO, BVAL, MO, MVAL]