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3.2.7 Internal Current Control in VVC
plus
Mode
The frequency converter features an integral current limit
control which is activated when the motor current, and
thus the torque, is higher than the torque limits set in
4-16 Torque Limit Motor Mode
,
4-17 Torque Limit Generator
Mode
and
4-18 Current Limit
.
When the frequency converter is at the current limit during
motor operation or regenerative operation, the frequency
converter will try to get below the preset torque limits as
quickly as possible without losing control of the motor.
3.2.8 Local (Hand On) and Remote (Auto
On) Control
The frequency converter can be operated manually via the
local control panel (LCP) or remotely via analog and digital
inputs and serial bus. If allowed in
0-40 [Hand on] Key on
LCP
,
0-41 [Off] Key on LCP
,
0-42 [Auto on] Key on LCP
, and
0-43 [Reset] Key on LCP
, it is possible to start and stop the
frequency converter via the LCP using the [Hand ON] and
[Off] keys. Alarms can be reset via the [RESET] key. After
pressing the [Hand ON] key, the frequency converter goes
into Hand mode and follows (as default) the Local
reference that can be set using arrow key on the LCP.
After pressing the [Auto On] key, the frequency converter
goes into Auto mode and follows (as default) the Remote
reference. In this mode, it is possible to control the
frequency converter via the digital inputs and various serial
interfaces (RS-485, USB, or an optional fieldbus). See more
about starting, stopping, changing ramps and parameter
set-ups etc. in parameter group 5-1* (digital inputs) or
parameter group 8-5* (serial communication).
130BP046.10
Hand
on
Off
Auto
on
Reset
Active Reference and Configuration Mode
The active reference can be either the local reference or
the remote reference.
In
3-13 Reference Site
the local reference can be
permanently selected by selecting
Local
[2].
To permanently select the remote reference select
Remote
[1]. By selecting
Linked to Hand/Auto
[0] (default) the
reference site will depend on which mode is active. (Hand
Mode or Auto Mode).
Remote
reference
Local
reference
Auto mode
Hand mode
Linked to hand/auto
Local
Remote
Reference
130BA245.11
LCP Hand on,
off and auto
on keys
P 3-13
Reference site
Torque
Speed open/
closed loop
Scale to
RPM or
Hz
Scale to
Nm
Scale to
process
unit
Process
closed loop
Local
ref.
Local
reference
Configuration
mode
Local
configuration
mode
130BA246.10
P 1-00
P 1-05
Hand OnAutoLCP Keys
3-13 Reference Site
Active Reference
Hand
Linked to Hand /
Auto
Local
Hand -> Off
Linked to Hand /
Auto
Local
Auto
Linked to Hand /
Auto
Remote
Auto -> Off
Linked to Hand /
Auto
Remote
All keys
Local
Local
All keys
Remote
Remote
Table 3.1 Conditions for Local/Remote Reference Activation.
1-00 Configuration Mode
determines what kind of
application control principle (i.e. Speed, Torque or Process
Control) is used when the remote reference is active.
1-05 Local Mode Configuration
determines the kind of
application control principle that is used when the local
reference is active. One of them is always active, but both
can not be active at the same time.
Introduction to FC 300
FC 300 Design Guide
22
MG.33.BD.02 - VLT
®
is a registered Danfoss trademark
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3