Precautions For Programming - Mitsubishi Electric MELSEC iQ-R Series Safety Manual

4.2

Precautions for Programming

Basic programming
Configure a program for realizing safety functions with attention to the following points.
• Program so that a machine is started only when safe state can be checked at the time the start switch is pressed.
• Program so that a machine is stopped if the safe state is not checked.
• Program so that a machine is started at the fall (onoff) of the signal of the start switch. The programming can prevent a
machine from accidentally starting at the switch failure (such as contact welding, spring damage).
• To inhibit restart without manual operation after safety functions were performed and outputs were turned off, create an
interlock program which uses a reset button for restart.
Operation function
(non-safety-related part)
Operation command
Start switch
Reset switch
For specific program examples, refer to the following.
Page 51 SAFETY APPLICATION CONFIGURATION EXAMPLES
4 PRECAUTIONS FOR USE OF SAFETY PROGRAMMABLE CONTROLLER
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4.2 Precautions for Programming
Start request
Safety
programmable
controller
Safety
input data
Safety state
No one is in the hazardous area.
There is no emergency stop request.
The safety programmable controller and safety
components are operating normally.
Safety output data
(start command signal)
Machine startup
Interlock