Delta RMC151 - Manual (Page 98)

RMC70/150 and RMCTools User Manual
The Open Loop Halt will ramp the Control output to zero, but will not remove the axis
from pressure/force limit. The Direct Output Halt (3) and Fault Controller (8) commands
will remove it from pressure/force limit.
Tip:
The Halts do more than just stop the axis. If you simply wish to stop the motion in open loop
control, use the Stop (Open Loop) (22) or Open Loop Rate (10) commands. If you wish to stop
the motion in closed loop control, use the Stop (Closed Loop) (6) command instead.
Triggering an Open Loop Halt
An Open Loop Halt can be triggered in two ways:
• By issuing the Open Loop Halt (2) command.
• Via Auto Stops.
After a Halt has Occurred
If the halt was caused by an Auto Stop, you should first make sure the error condition
that caused it has been resolved before continuing. Once it has been fixed, you can clear
the Halted status bit by issuing the Clear Faults (4) command. Issuing a valid motion
command will also clear the Halted status bit.
Why Bother?
This halt is useful when you want to set the Control Output to zero because of a
potentially dangerous error. The Open Loop Halt Ramp parameter is used to avoid an
abrupt (and potentially damaging) stop. If you just want to stop the axis but still have
closed loop control over it, use the Closed Loop Halt.
The Auto Stops can be set up to cause this halt when an error bit turns on.
3.4.5. Direct Output Halt
The Direct Output Halt is one of the four types of RMC Halts. Use the Direct Output Halt to halt
the axis, put it in Direct Output, and turn off the Enable Output.
When a Direct Out Halt occurs, it takes the following steps:
• It puts the axis in Direct Output, turns on the Direct Output status bit, and ramps
down the Control Output to zero using the Open Loop Halt Ramp parameter.
• When the Control Output reaches zero, this halt turns off the Enable Output.
• The Halted status bit is set and the axis is said to be in the halted state.
• If the axis is part of a Halt Group, it starts a Direct Output Halt on all axes in the
group.
Pressure/Force
The Open Loop Halt will remove the axis from pressure/force control or limit and put it in
Direct Output.
Tip:
The Halts do more than just stop the axis. For example, the Direct Output Halt will turn off the
Enable Output as well. If you simply wish to stop the motion in open loop control, use the Stop
(Open Loop) (22) or Open Loop Rate (10) command. If you wish to stop the motion in closed
loop control, use the Stop (Closed Loop) (6) command instead.
Triggering a Direct Output Halt
A Direct Output Halt can be triggered in two ways:
• By issuing the Direct Output Halt (3) command.
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