Danfoss VLT Series Design Manual page 127

VLT ® HVAC Drive Design Guide
6.1.5. Smart Logic Control
The smart logic control (SLC) is essentially a sequence of user-defined actions (see par. 13-52)
executed by the SLC when the associated user-defined
TRUE by the SLC.
Events
event [1]
event [2]
and actions are placed in array parameters.
Only one
(in the SLC) during the present scan interval and no other
that when the SLC starts, it evaluates
event [1]
It is possible to program from 0 to 20
actions
and
been executed, the sequence starts over
again from
tion shows an example with three
actions
6.1.6. Smart Logic Control Programming
A new, useful facility in VLT HVAC Drive is the Smart Logic Control (SLC).
In applications where a PLC generates a simple sequence, the SLC may take over elementary tasks
from the main control.
SLC is designed to act from event send to or generated in the VLT HVAC Drive . The adjustable
frequency drive will then perform the pre-programmed action.
6.1.7. SLC Application Example
One sequence 1:
Start – ramp-up – run at reference speed 2 sec – ramp-down and hold shaft until stop.
actions
and are each numbered and are linked in pairs called states. This means that when
is fulfilled (attains the value TRUE),
will be evaluated and, if evaluated TRUE,
event
will be evaluated at any time. If an
is evaluated TRUE does the SLC execute
event / action
. When the last
event [1] / action [1] . The illustra-
:
MG.11.B4.22 - VLT ® is a registered Danfoss trademark.
event
(see par. 13-51) is evaluated as
action [1]
is executed. After this, the conditions of
action [2]
will be executed and so on. Events
event
is evaluated as FALSE, nothing happens
events
event [1] event [1]
(and only
action [1]
and start evaluating
events
has
events /
6. Application Examples
will be evaluated. This means
) each scan interval. Only when
event [2]
.
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