Extreme Running Conditions - Danfoss VLT Midi Drive FC 280 Design Manual

Product Overview
Par. 13-51
SL Controller Event
Running
Warning
Torque limit
Digital input X 30/2
. . .
Par. 13-43
Logic Rule Operator 2
. . .
. . .
Par. 13-11
Comparator Operator
=
TRUE longer than..
. . .
. . .
Illustration 2.33 Associated Action
Events and actions are each numbered and linked in pairs
(states). This means that when event [0] is fulfilled (attains
the value TRUE), action [0] is executed. After this, the
conditions of event [1] are evaluated and if evaluated true,
action [1] is executed, and so on. Only 1 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 are evaluated. When the SLC starts, it
evaluates event [0] (and only event [0]) each scan interval.
Only when event [0] is evaluated true, the SLC executes
action [0] and starts evaluating event [1]. It is possible to
program 1–20 events and actions.
When the last event/action has been executed, the
sequence starts over again from event [0]/action [0].
Illustration 2.34 shows an example with 3 event/actions:
Start
event P13-01
State 1
13-51.0
13-52.0
Stop
event P13-02
State 4
13-51.3
13-52.3
Illustration 2.34 Sequence with 3 Events/Actions
MG07B102
Design Guide
Par. 13-52
SL Controller Action
Coast
Start timer
Set Do X low
Select set-up 2
. . .
State 2
13-51.1
13-52.1
Stop
event P13-02
State 3
13-51.2
13-52.2
Stop
event P13-02
Danfoss A/S © 03/2016 All rights reserved.
Comparators
Comparators are used for comparing continuous variables
(for example output frequency, output current, and analog
input) to fixed preset values.
Par. 13-11
Comparator Operator
Par. 13-10
Comparator Operand
=
TRUE longer than.
Par. 13-12
Comparator Value . . .
. . .
Illustration 2.35 Comparators
Logic rules
Combine up to 3 boolean inputs (true/false inputs) from
timers, comparators, digital inputs, status bits, and events
using the logical operators and, or, and not.
Par. 13-41
Logic Rule Operator 1
Par. 13-40
Logic Rule Boolean 1
Par. 13-42
Logic Rule Boolean 2 . . .
. . .
Par. 13-44
Logic Rule Boolean 3
Illustration 2.36 Logic Rules

2.11 Extreme Running Conditions

Short circuit (motor phase-to-phase)
The frequency converter is protected against short circuits
by current measurement in each of the 3 motor phases or
in the DC link. A short circuit between 2 output phases
causes an overcurrent in the frequency converter. The
frequency converter is turned off individually when the
short circuit current exceeds the permitted value (alarm 16,
Trip lock).
Switching on the output
Switching on the output between the motor and the
frequency converter is fully allowed, and does not damage
the frequency converter. However, fault messages may
appear.
2
Par. 13-43
Logic Rule Operator 2
. . .
. . .
43
2