Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

Страница: 129 / 207

event (see 13-51 SL Controller Event ) is evaluated as TRUE
by the SLC.
Events and actions are each numbered and are linked in
pairs called states. This means that when event [1] is
fulfilled (attains the value TRUE), action [1] is executed.
After this, the conditions of event [2] will be evaluated and
if evaluated TRUE, action [2] will be executed and so on.
Events and actions are placed in array parameters.
Only one event will be evaluated at any time. If an event is
evaluated as FALSE, nothing happens (in the SLC) during
the present scan interval and no other
events will be
evaluated. This means that when the SLC starts, it
evaluates
event [1] (and only event [1] ) each scan interval.
Only when event [1] is evaluated TRUE, the SLC executes
action [1] and starts evaluating event [2] .
It is possible to program from 0 to 20 events and actions .
When the last event / action has been executed, the
sequence starts over again from event [1] / action [1] . The
figure shows an example with three events / actions :
Figure 6.4
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.
Figure 6.5
Set the ramping times in 3-41 Ramp 1 Ramp Up Time and 3-42 Ramp 1 Ramp Down Time to the desired times
tramp =
tacc × nnorm (par. 1 − 25)
ref RPM
Set term 27 to No Operation ( 5-12 Terminal 27 Digital Input )
Application Examples
VLT
®
HVAC Drive Design Guide
MG11BB22 - VLT
®
is a registered Danfoss trademark 6-3
6 6