Appendix 8 General Safety Requirements - Mitsubishi Electric MELSEC iQ-R Series Configuration Manual

Appendix 8
General Safety Requirements
When a programmable controller is powered on or off, the control module may not output signals correctly for a moment due
to differences in the delay and startup times between the power supply for the programmable controller and the external
power supply (especially, DC power) for the control module.
Signals also may not be output correctly when the external power supply or the programmable controller fails.
In terms of fail-safe and to prevent any incorrect output signals from leading to the entire system failure, configure safety
circuits (such as emergency stop circuits, protection circuits, and interlock circuits) external to the programmable controller for
the parts where the incorrect output may cause damage to the machines or accidents.
This section shows system design circuit examples, considering the points described above.
When the C Controller module is used, refer to the following.
 MELSEC iQ-R C Controller Module User's Manual (Application)
A
APPX
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Appendix 8 General Safety Requirements