Internal Current Control In Vvcplus Mode; Local (Hand On) And Remote (Auto On) Control - Danfoss VLT AutomationDrive FC 300 Design Manual

3. Introduction to FC 300
3
In the shown configuration, par. 1-01
and par. 1-00 is set to "Speed closed loop [1]".
The motor control in this configuration relies on a feedback signal from an encoder mounted
directly on the motor (set in par. 1-02
Select "Speed closed loop [1]" in par. 1-00 to use the resulting reference as an input for the Speed
PID control. The Speed PID control parameters are located in par. group 7-0*.
Select "Torque [2]" in par. 1-00 to use the resulting reference directly as a torque reference.
Torque control can only be selected in the
Principle
It requires no torque feedback, since the actual torque is calculated on the basis of the current
measurement of the frequency converter.
Select "Process [3]" in par. 1-00 to use the process PID control for closed loop control of e.g.
speed or a process variable in the controlled application.

3.2.7. Internal Current Control in VVCplus 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 par. 4-16, 4-17 and
4-18.
When the frequency converter is at the current limit during motor operation or regenerative op-
eration, 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 par. 0-40, 0-41, 0-42, and 0-43, 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 frequen-
cy 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 se-
rial interfaces (RS-485, USB, or an optional
24
) configuration. When this mode has been selected, the reference will use the Nm unit.
MG.33.B9.02 - VLT
Motor Control Principle is set to "Flux w motor feedb [3]"
Motor Shaft Encoder Source ).
Flux with motor feedback
fieldbus). See more about starting, stopping,
changing ramps and parameter set-ups etc. in
par. group 5-1* (digital inputs) or par. group
8-5* (serial communication).
® is a registered Danfoss trademark
FC 300 Design Guide
(par. 1-01 Motor Control