138
Failsafe Circuits
Section 2-4
2-4-3
Failures in the Feedback System
Sensors can be mounted in dangerous areas to stop the machine by turned
OFF the main circuits of the Servo Drivers. To be sure that the failsafe mea-
sure is dependable, sensors are mounted in areas where the machine must
never enter. If a sensor is activated, a dynamic brake is applied to the Servo
Drivers, the Servo Driver main circuits are turned OFF, other similar measures
are taken.
2-4-4
Other Safety Features
The following functions are also available to aid in implementing safety mea-
sures.
Wiring Check
A wiring check can be performed the first time a servo is locked after starting
or restarting the MC Unit. Both the command system and feedback system
wiring is checked. Refer to
2-3-10 Wiring Check Function
for details.
Software Limits
Clockwise and counterclockwise limits can be set in the software to prevent
motion outside of a specific range. An error will occur and the axis will be
decelerated to a stop if a software limit is exceeded. Refer to
Positive (+) and
Negative (–) Software Limits
on page 178 for details.
Feedback Pulse Error
Detection
An error will occur if the feedback pulse from the encoder exceeds 500 kpps.
When this happens, a speed reference voltage of 0 V will be output to the
Servo Driver for 0.5 s and then the operation command output to the Servo
Driver will be turned OFF.
Normal range of movement
CCW limit input
Prohibited area
Sensor
CPU
Unit
Operation
command
output
MC
Unit
Voltage
output
X axis
Servo
driver
External output
Sensor
controller
Sensor
CW limit input
Prohibited area
Sensor
Servomotor
Summary of Contents for CS1W-MC221 -
Page 1: ...Motion Control Units Cat No W359 E1 04 CS1W MC221 V1 421 V1 OPERATION MANUAL ...
Page 2: ...CS1W MC221 V1 421 V1 Motion Control Units Operation Manual Revised February 2008 ...
Page 3: ...iv ...
Page 5: ...vi ...
Page 11: ...xii ...
Page 15: ...xvi ...
Page 19: ...xx ...
Page 27: ...xxviii Conformance to EC Directives 6 ...
Page 133: ...106 Installation Section 2 2 2 2 4 Dimensions CS1W MC421 CS1W MC221 ...
Page 173: ...146 Connecting Peripheral Devices Section 2 7 ...
Page 227: ...200 Command Area Section 3 6 ...
Page 351: ...324 Interface Specifics Section 5 4 ...
Page 513: ...486 Absolute Encoder Interface Specifications Section 9 7 ...
Page 575: ...548 Error Log Section 12 6 ...
Page 589: ...562 Performance Appendix A ...
Page 655: ...628 Control Bit Flag Timing Charts Appendix E ...
Page 683: ...656 Origin Search Patterns Appendix F ...
Page 685: ...658 Encoder Divider Rate and Rotation Speed for OMRON Servo Drivers Appendix G ...