User Manual

Logical I/O blocks
General functions
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The ramp-up/down times (run-up/-down times) can be defined in a table for each stage. These times
apply to the two switch types [SwiKind]
Normal and Motor .
The ramp-up time is the time taken by a motor when changing from a lower speed to the next higher
speed, to reach the new speed. This limits the current consumption of the motor.
The ramp-down time is the time taken by the motor when switching down from a higher speed, to reach
the lower speed. This prevents feedback to the mains supply network and protects the fan belt and the
motor.
As a rule, the ramp-up and ramp-down times depend on the centrifugal mass involved, and must be
determined separately for each project.
Especially with single-speed motors, the times can be used as Open/Close runtimes (e.g., damper actuator
from 0…100%). A moving damper can thus be mapped in the system and the transition signal can, if
required, be used for control purposes.
Monitoring periods
Feedback monitoring / process value monitoring
Blocks: BI, MI, BO, MO, BVAL, MVAL
The I/O objects have a monitoring function. The output objects monitor the feedback signal from the plant.
For this purpose, an address string must be entered for the [FbAddr] feedback parameter [FbAddr] and the
alarm function must be enabled.
The input and value objects can monitor reference values. For this purpose, the relevant reference values
must be configured and the alarm function must be enabled.
Deviation monitoring
If the feedback value deviates from the output value [PrVal], a deviation alarm is generated after a
configurable time period, and the block status changes to
In Alarm . When the two values match again, and
the configured time period has expired, the alarm and status are reset. There is otherwise no automatic
block reaction, that is, if a switch response in the plant is required as a reaction to this alarm, this response
must be programmed in CFC via the Disturbance output [Dstb].
Switch-on/off feedback monitoring
It is also possible to configure the time period during which the maximum deviation of the feedback signal
may occur after a switch-on/off operation. If the deviation persists after the monitoring time has expired,
an alarm is generated and the status of the block changes to
In alarm . When the two values match again,
and the configured time period has expired, the alarm and status are reset. There is otherwise no
automatic block reaction, that is, if a switch response in the plant is required as a reaction to this alarm,
this response must be programmed in CFC via the Disturbance output [Dstb].
No feedback monitoring
If no feedback monitoring is required, and the address string is left blank, the monitoring periods are used
by the block for the internal generation of the transient state [TraSta]. This means that the transient state
signal for the switch-on/off operation is set for the preset period of time. This is how a moving actuator,
e.g., a damper, is displayed in the system.