Input Protection Lines
Abort
- A low input stops commanded motion instantly without a controlled deceleration. For
any axis in which the Off-On-Error function is enabled, the amplifiers will be disabled. This
could cause the motor to ‘coast’ to a stop. If the Off-On-Error function is not enabled, the motor
will instantaneously stop and servo at the current position. The Off-On-Error function is further
discussed in this chapter.
Forward Limit Switch
- Low input inhibits motion in forward direction. If the motor is moving
in the forward direction when the limit switch is activated, the motion will decelerate and stop. In
addition, if the motor is moving in the forward direction, the controller will automatically jump to
the limit switch subroutine, #LIMSWI (if such a routine has been written by the user). The CN
command can be used to change the polarity of the limit switches.
Reverse Limit Switch
- Low input inhibits motion in reverse direction. If the motor is moving in
the reverse direction when the limit switch is activated, the motion will decelerate and stop. In
addition, if the motor is moving in the reverse direction, the controller will automatically jump to
the limit switch subroutine, #LIMSWI (if such a routine has been written by the user). The CN
command can be used to change the polarity of the limit switches.
Software Protection
The DMC-1600 provides a programmable error limit. The error limit can be set for any number
between 1 and 32767 using the ER n command. The default value for ER is 16384.
Example:
ER 200,300,400,500
Set X-axis error limit for 200, Y-axis error limit to 300, Z-axis error limit to 400
counts, W-axis error limit to 500 counts
ER,1,,10
Set Y-axis error limit to 1 count, set W-axis error limit to 10 counts.
The units of the error limit are quadrature counts. The error is the difference between the
command position and actual encoder position. If the absolute value of the error exceeds the value
specified by ER, the DMC-1600 will generate several signals to warn the host system of the error
condition. These signals include:
Signal or Function
State if Error Occurs
# POSERR
Jumps to automatic excess position error subroutine
Error Light
Turns on
OE Function
Shuts motor off if OE1
AEN Output Line
Goes low
The Jump on Condition statement is useful for branching on a given error within a program. The
position error of X,Y,Z and W can be monitored during execution using the TE command.
Programmable Position Limits
The DMC-1600 provides programmable forward and reverse position limits. These are set by the
BL and FL software commands. Once a position limit is specified, the DMC-1600 will not accept
position commands beyond the limit. Motion beyond the limit is also prevented.
Example:
DP0,0,0 Define
Position
BL -2000,-4000,-8000
Set Reverse position limit
FL 2000,4000,8000
Set Forward position limit
JG 2000,2000,2000
Jog
DMC-1600
Chapter 8 Hardware & Software Protection
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