Danfoss VLT Series Programming Manual page 23

Servo Drive Operation
If a state transition is requested, the related actions are processed completely before transitioning to the new state. For
example, in state Operation enabled, when the disable operation command is received, the servo drive remains in state
Operation enabled until the disable operation function (see chapter 7.20.9 Parameter 50-49: Disable Operation Option Code
(0x605C)) is completed.
Drive function is disabled means that no energy is supplied to the motor. Target or setpoint values (for example, torque,
velocity, position) are not processed. Drive function is enabled means that energy is supplied to the motor. Target or setpoint
values are processed.
If a fault is detected in the servo drive, a transition to state Fault reaction active takes place. In this state, the state machine
executes a special fault reaction (see chapter 7.20.1 Parameter 50-41: Fault Reaction Option Code (0x605E)). After the execution
of this fault reaction, the servo drive automatically switches to state Fault. This state can only be left by using the fault reset
command, but only if the fault is no longer active.
If a fatal error occurs, the servo drive is no longer able to control the motor, so the servo drive must be switched off
immediately. If a fatal error has occurred, the servo is trip-locked and cannot be reset via fieldbus.
The behavior of drive disabling, quick stop, halt, and fault reaction functions are configurable via the objects defined in
chapter 7.20 Option Code Objects.
If a brake is present, the high-level power is switched off after a delay time in order to apply the brake.
2.3.2 Factor Group
Use the factor group to set the user-defined units required
in the application.
The user-defined units are:
•
Position units
•
Velocity units
•
Acceleration units
These units are used for all objects that support user-
defined units (for example, position actual value, profile
velocity, and profile acceleration).
Changing the objects in the factor group has an
immediate effect on all objects that support user-defined
units. Their numerical values stay the same, but they are
interpreted differently (according to the new scaling factors
of the factor group). All numerical values are interpreted
using the current settings of the factor group.
NOTICE
If the factor group is changed, then the default values
are interpreted differently.
The formulae in this chapter show the calculation of the
units. Objects, whose values are not dependent on the
factor group, have fixed units specified with the objects.
The objects of the factor group can be found in
chapter 7.4 Factor Group Objects.
MG36D102
Programming Guide
Position units:
The position value is calculated as:
Position value =
Position value means all objects containing values in user-
defined position units.
Position internal value is given in encoder increments.
Velocity units:
The velocity value is calculated as:
Velocity value =
Velocity internal value is the position internal value(s),
resulting in the following formula:
Velocity value =
Velocity value means all objects containing values in user-
defined velocity units.
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position internal value x feed constant
position encoder resolution x gear ratio
velocity internal value x feed constant
velocity encoder resolution x gear ratio
position value
x velocity factor
s
2 2
x velocity factor
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