User guide

Parameter Descriptions www.controltechniques.com 129
temporarily disable the travel limit fault capability of the
SM-EZMotion module. When TravelLimitDisable is
activated, the SM-EZMotion module travel limits (hardware
or software) are no longer valid. If disabled using a
program, the travel limits will automatically be re-enabled
when the program ends, if they haven’t already been
enabled. This feature is typically used when a machine
must use one of its limit switches as a home switch. The
user disables the travel limits, then homes to the limit
switch, and then re-enables the travel limit.
Travel Limit Minus Activate
TravelLimitMinusActivate
This destination is used to activate the travel limit minus
fault. It should be assigned to the travel limit minus sensor.
When it is activated the drive will decelerate to a stop using
the deceleration rate defined in the TravelLimitDecel
parameter. This is level sensitive.
Travel Limit Plus Activate
TravelLimitPlusActivate
This destination is used to activate the travel limit plus fault.
It should be assigned to the travel limit plus sensor. When
it is activated the drive will decelerate to a stop using the
deceleration rate defined in the TravelLimitDecel
parameter. This is level sensitive.
Travel Limit Minus Active
TravelLimitMinusActive
This source is active when the TravelLimitMinusActivate is
active.
Travel Limit Plus Active
TravelLimitPlusActive
This source is active when the TravelLimitPlusActivate is
active.
Variable Decimal
Var.Var#.Decimal
This parameter specifies the number of decimal placed of
resolution that this particular user variable will use.
Minimum value is 0 (default), and the maximum number of
decimal places in 6 (0.000000). When assigning the value
of a User Variable to different parameters, make sure that
the parameter and the User Variable have the same
number of decimal places.
Variable Value
Var.Var#.Value
This parameter specifies the current value of a user
variable. In a program, the ".Value" portion of the
parameter name can be left off. For example:
Var.Var0.Value = 12345 is the same as Var.Var0 = 12345
When assigning the value of a User Variable to different
parameters, make sure that the parameter and the User
Variable have the same number of decimal places.
Velocity Command
VelCommand
The Velocity Command is the velocity that the
SM-EZMotion module is commanding the motor to run at.
This command is generated by the drive velocity control
loop. It is displayed in user units.
Velocity Feedback
VelFeedback
This is the feedback (or actual) velocity. It will always return
the actual motor velocity, even in synchronized
applications in which the master axis is halted during a
move.
Velocity Feedforward Enable
VelocityFeedforwardEnable
The Velocity Feedforward applies the calculated velocity
command directly to the Unidrive SP velocity loop.
Enabling the Velocity Feedforward will generally yield
faster velocity response (reaches programmed velocity
much faster), but can introduce some velocity overshoot.
N
ote
If your application requires jogging motion, the Enable
Velocity Feedforward should always be active.
Velocity Loop Bandwidth
VelocityLoopBandwidth
The Velocity Loop Bandwidth parameter is the theoretical
bandwidth of the velocity controller (how fast the system
can respond to change in velocity command). The value of
this parameter depends heavily on the correct values for
the motor data, particularly the Motor Rotor Inertia and the
Motor Current Constant (Ke). Units for this parameter are
Hz.
Time Scale
VelocityUnits.TimeScale
Velocity time scale can be set to user units per second or
user units per minute, used for all real-time velocities
throughout the PowerTools Pro software.