Delta RMC151 User Manual
Page 716
RMC70/150 and RMCTools User Manual
Firmware Requirement: 1.00 or newer
See the Commands Overview topic for basic command information and how to issue
commands from PLCs, HMIs, etc.
Command Parameters
# Parameter Description
Range
1 Deceleration Rate (pos-units/s
2
)
>0
Description
This command stops the axis in closed loop control, bringing the velocity to zero at the
specified Deceleration Rate. The behavior of this command depends on the type of
control of the axis at the moment this command is received:
•
Position PID
The Target Position stops by ramping the current Target Velocity to zero using the
specified Deceleration Rate, while remaining in position control.
•
Position I-PD
If the last motion command was Move Absolute (I-PD) (28) or Move Relative (I-PD)
(29), the Target Position will be moved toward the current position to ensure a quicker
yet smooth stop. Otherwise, the Target Position will be stopped by ramping the
current Target Velocity to zero using the specified Deceleration Rate, while
remaining in position control.
•
Velocity PID
The Target Velocity will ramp down from the current velocity to zero using the
specified Deceleration Rate, while remaining in velocity control.
•
Velocity I-PD
If the last motion command was Move Velocity (I-PD) (38), the Target Velocity will
stop immediately. Otherwise, the velocity will ramp down from the current velocity to
zero using the specified Deceleration Rate, while remaining in velocity control.
•
Open Loop
The axis transitions to closed-loop control and ramps the velocity to zero using the
specified Deceleration Rate in V/sec.
If you wish to stop the axis, but not remain in closed loop control, consider using the Stop
Closed Loop Stopping of the Actual versus Target Position
The Stop (Closed Loop) command will stop the Target Position. Therefore, if the Actual is
lagging significantly behind the target, the axis will actually continue moving until it
reaches the stopped Target Position. If the Actual is lagging and you want the Actual
Position to stop immediately, you can put the axis in open loop control (which sets the
Target Position to the Actual Position) for one loop time, then issue the Stop (Closed
Loop) command. This can be done in a user program. In the first step, issue the Open
Loop Rate command. In the Output command parameter, put the Control Output. This
will keep the Control Output from changing drastically. Then choose the Immediate link
type and make the next step issue a Stop (Closed Loop) command. On most well-tuned
systems, this issue is typically not a concern.
Status Bits
In Position Bit
The In Position status bit will not be set. Do not attempt to use the In Position bit to tell if
the axis has stopped after a Stop (Closed Loop) (6) command.
Target Generator State Bits
696
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