Galil DMC-1700, DMC-1800 user manual Off-On-Error, Automatic Error Routine, Limit Switch Routine

Off-On-Error

The DMC-1700/1800 controller has a built in function which can turn off the motors under certain error conditions. This function is know as ‘Off-On-Error”. To activate the OE function for each axis, specify 1 for X,Y,Z and W axis. To disable this function, specify 0 for the axes. When this function is enabled, the specified motor will be disabled under the following 3 conditions:

1.The position error for the specified axis exceeds the limit set with the command, ER

2.The abort command is given

3.The abort input is activated with a low signal.

Note: If the motors are disabled while they are moving, they may ‘coast’ to a stop because they are no longer under servo control.

To re-enable the system, use the Reset (RS) or Servo Here (SH) command. Examples:

OE 1,1,1,1	Enable off-on-error for X,Y,Z and W
OE 0,1,0,1	Enable off-on-error for Y and W axes and disable off-on-error for W and Z axes

Automatic Error Routine

The #POSERR label causes the statements following to be automatically executed if error on any axis exceeds the error limit specified by ER. The error routine must be closed with the RE command. The RE command returns from the error subroutine to the main program.

NOTE: The Error Subroutine will be entered again unless the error condition is gone. Example:

#A;JP #A;EN	“Dummy” program
#POSERR	Start error routine on error
MG “error”	Send message
SB 1	Fire relay
STX	Stop motor
AMX	After motor stops
SHX	Servo motor here to clear error
RE	Return to main program

NOTE: An applications program must be executing for the #POSERR routine to function.

Limit Switch Routine

The DMC-1700/1800 provides forward and reverse limit switches which inhibit motion in the respective direction. There is also a special label for automatic execution of a limit switch subroutine. The #LIMSWI label specifies the start of the limit switch subroutine. This label causes the statements following to be automatically executed if any limit switch is activated and that axis motor is moving in that direction. The RE command ends the subroutine.

The state of the forward and reverse limit switches may also be tested during the jump-on-condition statement. The _LR condition specifies the reverse limit and _LF specifies the forward limit. X,Y,Z, or W following LR or LF specifies the axis. The CN command can be used to configure the polarity of the limit switches.

Limit Switch Example:

#A;JP #A;EN	Dummy Program
#LIMSWI	Limit Switch Utility
V1=_LFX	Check if forward limit
V2=_LRX	Check if reverse limit

DMC-1700/1800 Chapter 8 Hardware & Software Protection • 179