Mitsubishi Electric MELFA CR750 Series Instruction Manual page 49

(6) Position monitoring
During the position monitoring, the function monitors four monitoring positions to see if they do not exceed
the position monitoring plane applied at that time.
If a monitoring position approaches the position monitoring plane during the operation performed by the
interpolation command or for the jog operation, the robot stops its operation (SLP pre-stop status). The
behaviors at the stop near the position monitoring plane are as follows.
(a) During the operation performed by the interpolation command
The [RUN] state is maintained for the automatic operation of the program. The robot operation is stopped,
and the execution does not proceed and stops at the line of the interpolation command, but the state
does not change to [STOP].
If the target position monitoring plane does not exist in the vicinity due to the monitoring mode change to
disable the target position monitoring plane, the SLP pre-stop status is reset and the operation resumes.
Besides, when the automatic operation enters the [STOP] state due to a stop input or error occurrence,
the SLP pre-stop status is also reset.
CAUTION
(b) During the operation performed for the jog operation
A buzzer goes off from the teaching pendant to notify that the position monitoring plane is accessed, and
the robot stops.
Besides, if the function detects that any one of the monitoring positions exceeds the plane, error H220 m (m
is a plane number) occurs and the robot turns the servo OFF to stop. The position monitoring is performed
for three types of positions (position command, position feedback, and servo position). The error message of
error H220 m changes according to the detected position.
CAUTION
CAUTION
When the monitoring mode is switched, the robot may start motion.
Be careful in changing the monitoring mode.
The function to stop the movement at the position near the position monitoring plane is
activated against a motion command by the interpolation command or for the jog
operation. The function is not activated against a correction command of the compliance
control, force sense control, or tracking function.
Therefore, even if the motion command is stopped near the position monitoring plane
during operation of such functions operation, the target position may reach the position
monitoring plane to cause an error.
The function to stop the movement near the position monitoring plane is not activated
against the real-time external control (Mxt command).
4 Safety monitoring function
Safety monitoring function 4-37