User`s manual

Operation

4-6

4. Operation

4.3 Emergency stop

To safely stop the robot in case of an emergency, configure an emergency stop circuit

while referring to the explanations below.

For details on input terminal functions and parameters, refer to 5.2, "Input terminal

functions" and 6.3.2, "Setup parameter description".

(1) Servo OFF

When the SON signal is turned off, the servo is OFF and the braking is applied by the

dynamic brake.

• The DB Operation selection (FA-16) must be set to "SoF". The braking is not applied

by the dynamic brake unless this selection is set to "SoF".

• When the Servo OFF wait time (FA-24) is set, the servo is OFF and the braking is

applied by the dynamic brake after the SON signal has been turned off and the

servo OFF wait time has elapsed.

(2) How to shorten the braking distance

Shorten the breaking distance by producing the deceleration torque through the servo

control.

Example) Deceleration torque is produced by clamping the speed command at zero.

• The servo OFF wait time is set, and the SON signal and FOT/ROT signal

are turned off at the same time in case of an emergency.

• The speed command is clamped at zero by the FOT/ROT signal OFF

while the servo OFF is delayed. At this time, the deceleration torque is

produced to shorten the braking distance.

FOT

ROT

Current speed

Speed command

Servo

Main power

SON

FA-24

Note 1: If the heavy braking is applied as described in the example shown above

when the payload of the robot is large or offset, the deceleration torque

becomes too large, causing the robot to break. In this case, it is

recommended that the FOT/ROT signal is not turned off and the position

command is changed so that the speed command changes gradually.

Note 2: When the servo is OFF if a trip occurs, the power to the motor is shut down

immediately even when the Servo OFF wait time has been set.