3.9.2 Brake Resistor Cabling
EMC (Twisted Cables/Shielding)
Twist the wires to reduce electrical noise between the
brake resistor and the adjustable frequency drive. For
enhanced EMC performance, use a metal shield.
3.10 Smart Logic Controller
Smart Logic Control (SLC) is essentially a sequence of user-
defined actions (see 13-52 SL Controller Action [x]) executed
by the SLC when the associated user-defined event (see
13-51 SL Controller Event [x]) is evaluated as TRUE by the
SLC.
The condition for an event can be a particular status or
when the output from a Logic Rule or a Comparator
Operand becomes TRUE. This leads to an associated action
as shown in Figure 3.35.
. . .
. . .
Par. 13-11
Comparator Operator
Par. 13-43
Logic Rule Operator 2
Par. 13-51
SL Controller Event
Par. 13-52
SL Controller Action
130BB671.13
Coast
Start timer
Set Do X low
Select set-up 2
. . .
Running
Warning
Torque limit
Digital input X 30/2
. . .
=
TRUE longer than..
. . .
. . .
Figure 3.35 Current Control Status/Event and Action
Events and actions are each numbered and linked together
in pairs (states). This means that when [0] event is fulfilled
(attains the value TRUE), [0] action is executed. After this,
the conditions of [1] event are evaluated and if evaluated
TRUE, [1] action will be executed and so on. Only one
event is evaluated at any time. If an event is evaluated as
FALSE, nothing happens in the SLC during the current scan
interval and no other events will be evaluated. This means
that when the SLC starts, it evaluates only [0] event each
scan interval. Only when [0] event is evaluated TRUE, will
the SLC execute [0] action and start evaluating [1] event. It
is possible to program from 1 to 20 events and actions.
When the last event/action has been executed, the
sequence starts over again from [0] event/[0] action.
Figure 3.36 shows an example with three event/actions:
Figure 3.36 Internal Current Control Example
Comparators
Comparators are used for comparing continuous variables
(output frequency, output current, and analog input) to
fixed preset values.
Par. 13-11
Comparator Operator
=
TRUE longer than.
. . .
. . .
Par. 13-10
Comparator Operand
Par. 13-12
Comparator Value
130BB672.10
Figure 3.37 Comparators
Product Introduction Design Guide
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